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Re: [microhydro] Does Someone know this Turbine-Generator-ELC ??

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  • Soundararajan Ramasamy
    Dear Sir,   Kindly let us know your Phone number. with code and full address. We hope we can help you in running the turbine. Thanks & Regards for Vinci Aqua
    Message 1 of 15 , Aug 1, 2012
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      Dear Sir,
       
      Kindly let us know your Phone number. with code and full address. We hope we can help you in running the turbine.

      Thanks & Regards

      for Vinci Aqua Systems Pvt Ltd
      R.Soundararajan
      Managing Director

      --- On Wed, 1/8/12, Thor <thor@...> wrote:


      From: Thor <thor@...>
      Subject: [microhydro] Does Someone know this Turbine-Generator-ELC ??
      To: microhydro@yahoogroups.com
      Date: Wednesday, 1 August, 2012, 3:21 AM



       



      Hi everybody.

      First I was only going to ask if anybody had seen the ELC in the pictures I posted, but then decided to tell the full story as I far as I know it.

      I have been asked for help to get this Micro Hydro setup running properly. It was ordered and installed last year but so far almost nothing has worked as expected.

      Today I visited the site and took some pictures and measurements, (see group photos, album China-Turbine-In-Iceland http://groups.yahoo.com/group/microhydro/photos/album/1255983797/pic/list.

      The total head is approx. 50m, the static pressure with no flow is 4.8bar which drops to 3.0 bar at maximum needle valve opening.

      There is plenty of water, the pipe is always full.

      I was told the upper part of the penstock is 200m long HDPE pipe 110/6mm (internal dia. 108mm)
      The lower part is 40m long HDPE 90/8mm (internal dia. 84mm)
      there is also a short (1m long, less than 70mm dia.?) steel pipe where the penstock connects to the turbine.

      They ordered and got a turbine/generator rated for 50Hz/230V/3kW, 1500rpm at 40m head. It was known that the pipe would limit the flow and they did expect to run at approx. 80% pressure.

      First problem: The turbine did not come with a needle valve, just a far too wide fixed nozzle, so the owners made one, rather difficult to turn, but does not leak and seems to work all right.

      Second problem: slip ring damage.
      The generator is single phase with 2 slip rings and 2 brushes on each ring. The brush holders are made from thin sheet metal, the brushes are very loose and originally they were positioned some 15-20mm away from the rings so the brushes got stuck in the holders with arcing and ring damage. The rings have been repaired and the position of brush holders has been fixed somewhat, but it is still not good.

      Third problem: The ELC has never worked properly. It has a single 3kW dump load controlled by a TRIAC. It senses the voltage and fortunately the generator seems properly made to give 220-230V at 50Hz.
      But the ELC does not work smoothly, it either diverts no power to the dump load or far too much so the voltage and speed are just fluctuating wildly 170-240V 40-55Hz. The ELC has IC TL494CN which controls the TRIAC via MOC3020 Optocoupler. The TRIAC is unknown. The manufacturer used grinder on all the markings but failed to delete the IC´s :-)

      Fourth problem: The power output is much lower than expected, it seems to be at maximum running at 3.6bar pressure but then it is only approx. 5.6A x 230V = 1.3kW
      We measured the last one at 50Hz, it is a bit more if we lower speed and voltage, 40Hz 170V 12.1A = 2.1kW

      By measuring the distance from nozzle to shaft it looks like effective diameter of wheel is approx. 190mm. I think that is a bit too big for 1500rpm at 40m head.

      Any information regarding this appreciated.

      Best regards.

      Thor.
      (Electronics technician and a long time lurker in this group)








      [Non-text portions of this message have been removed]
    • Nando
      Thor : The ELC is a common PWM voltage regulator in reverse mode, this means that it is reading the rectified output voltage and if is higher than the
      Message 2 of 15 , Aug 1, 2012
      • 0 Attachment
        Thor :

        The ELC is a common PWM voltage regulator in reverse mode, this means that it is reading the rectified output voltage and if is higher than the reference starts to PWM modulate the power resistor to bring the voltage down via 50 HZ phase loading.

        This regulator is poor, the TL494 is the equivalent to the SG3825 family and has a wrong use.

        The TL494 has two amplifiers, one defined for current detection that can be used to detect the Zero crossing but due to the oscillator circuit the detector requires a clamp to limit the behavior of the oscillator lower transitional and keep the saw tooth working properly, and the second amplifier to detect the voltage fluctuations to turn ON the output pulse for the TRIAC ON position in the 180 degrees angle of the sine wave.

        This design is better for a Vdc control and I may wonder if the TRIAC is not a TRIAC but a MosFet -- does the device have a heat sink dissipator ?. Can you read the voltage that triggers the device to see if it is 12 volts with a width time equal to less than 180 degrees or around 2 or 3 volts ( if it is a TRIAC).

        The ELC in this case would have been better using two 555 IC, one as a Cero crossing point trigger with the time constant varied by the rectified voltage to trigger the second 555 to give a 30 or so microseconds pulse to turn the Triac ON phase wise, from the 180 degrees backwards incremented. -- This I did shortly after the 555 appeared in the market converting an equivalent circuit using a lot of discrete parts .

        Basically the ELC needs a cero crossing detector to trigger or reset an saw tooth oscillator with the amplitude of the saw tooth varied by the variable AC voltage ( rectified and slightly filtered) to cross the upper trigger point prior the reaching of the 50 Hz ( 20 ms) 180 degrees crossing to trigger the second 555 to generate the 30 or so microseconds to trigger the triac.

        We also need an amplifier to be able to modulate the saw tooth against a voltage reference.

        There is a need of a good motor Running Capacitor , connected in parallel to the generator ) to reduce the sine wave distortion that the TRIAC ON pulses generate.

        The head needed is defined by the PCD diameter of the turbine and the frequency to give the peripheral velocity of the turbine.

        The dynamic pressure drops too much !!

        The 40 meters 84 mm diameter is presenting too much water friction !! The 1 meter long 70 mm diameter is reducing the water volume too much !!

        To determine the HEAD

        So for a 1500 RPM turbine the RPS is 1500/60 sec = 25 RPS

        H= Head

        25 RPS * pi * Diameter turbine

        25 * 3.14 * 0.19 = 14,92 m/s

        Vjet = 100/49* 14,92= 30,45 m/s

        30,45 ^2 = 2 * 9,81 * H where H = 47,27m/s Which is close to the reported : about 50 meters static ,

        For a 3 KW the ELC should control two - 1 KW full ON/OFF loads plus the primary phase controlled 1 KW load as a minimum for best operation, though I would make the ELC differently and in this case a primary phase loaded 500 watts, a second full ON/OFF 500 watts , then 2 - 1 KW each load to have a full complement loading , this if the maximum power is 3 KW, though I would suggest the last 1 KW load to be a 1,5 KW load in case that the generator can produce more than 3 KW.

        Nando

        ----- Original Message -----
        From: Thor
        To: microhydro@yahoogroups.com
        Sent: Tuesday, July 31, 2012 16:51
        Subject: [microhydro] Does Someone know this Turbine-Generator-ELC ??



        Hi everybody.

        First I was only going to ask if anybody had seen the ELC in the pictures I posted, but then decided to tell the full story as I far as I know it.

        I have been asked for help to get this Micro Hydro setup running properly. It was ordered and installed last year but so far almost nothing has worked as expected.

        Today I visited the site and took some pictures and measurements, (see group photos, album China-Turbine-In-Iceland http://groups.yahoo.com/group/microhydro/photos/album/1255983797/pic/list.

        The total head is approx. 50m, the static pressure with no flow is 4.8bar which drops to 3.0 bar at maximum needle valve opening.

        There is plenty of water, the pipe is always full.

        I was told the upper part of the penstock is 200m long HDPE pipe 110/6mm (internal dia. 108mm)
        The lower part is 40m long HDPE 90/8mm (internal dia. 84mm)
        there is also a short (1m long, less than 70mm dia.?) steel pipe where the penstock connects to the turbine.

        They ordered and got a turbine/generator rated for 50Hz/230V/3kW, 1500rpm at 40m head. It was known that the pipe would limit the flow and they did expect to run at approx. 80% pressure.

        First problem: The turbine did not come with a needle valve, just a far too wide fixed nozzle, so the owners made one, rather difficult to turn, but does not leak and seems to work all right.

        Second problem: slip ring damage.
        The generator is single phase with 2 slip rings and 2 brushes on each ring. The brush holders are made from thin sheet metal, the brushes are very loose and originally they were positioned some 15-20mm away from the rings so the brushes got stuck in the holders with arcing and ring damage. The rings have been repaired and the position of brush holders has been fixed somewhat, but it is still not good.

        Third problem: The ELC has never worked properly. It has a single 3kW dump load controlled by a TRIAC. It senses the voltage and fortunately the generator seems properly made to give 220-230V at 50Hz.
        But the ELC does not work smoothly, it either diverts no power to the dump load or far too much so the voltage and speed are just fluctuating wildly 170-240V 40-55Hz. The ELC has IC TL494CN which controls the TRIAC via MOC3020 Optocoupler. The TRIAC is unknown. The manufacturer used grinder on all the markings but failed to delete the IC´s :-)

        Fourth problem: The power output is much lower than expected, it seems to be at maximum running at 3.6bar pressure but then it is only approx. 5.6A x 230V = 1.3kW
        We measured the last one at 50Hz, it is a bit more if we lower speed and voltage, 40Hz 170V 12.1A = 2.1kW

        By measuring the distance from nozzle to shaft it looks like effective diameter of wheel is approx. 190mm. I think that is a bit too big for 1500rpm at 40m head.

        Any information regarding this appreciated.

        Best regards.

        Thor.
        (Electronics technician and a long time lurker in this group)





        [Non-text portions of this message have been removed]
      • Thor
        Nando. Many thanks for your detailed reply. The ELC is all wrong as you said, I traced the PCB, drew a schematic with ExpressPCB and uploaded a GIF image of
        Message 3 of 15 , Aug 2, 2012
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          Nando.

          Many thanks for your detailed reply.

          The ELC is all wrong as you said, I traced the PCB, drew a schematic with ExpressPCB and uploaded a GIF image of the result in the photos, must remember to put a strong warning there so nobody thinks it is good and tries to make one!!

          I can not see it detects zero crossing at all, only the rectified DC-supply voltage to the ELC itself.

          The big load switching semiconductor is a TRIAC, infinite resistance between MT1 and MT2 both ways and approx. 100ohms gate to MT1. The MOC3020 is an instant switching Opto-TRIAC.

          I have one or two old ELCs I once made lying around, they were originally designed for a bit more power, 10-30kW, have 15 fixed zero switching ON/OFF loads and one variable phase controlled load which was 2x bigger than the fixed loads.

          The fixed loads turn on one by one (count up) if the variable load is at more than 75% and they turn off (count down) if the variable load is less than 25%.

          In this case it should be enough to have 4x500W fixed loads and one 1000W variable. (Of course it would be fun to mount 15x200W old light bulbs in a row as loads and and have two parallel bulbs as the variable. Unfortunately that would not last long enough !!)

          The pipe is another problem, the turbine maker put a 2" pipe thread on the input so that explains the very narrow short section at the turbine.

          The jet diameter is unknown to me, from the picture I took it looks like it may be about 30mm. Is that all right ?

          Then there is the wheel, it somehow does not look quite right, the Hartvigsen Hydro spoons look so much better :-)

          I also noticed in the picture of the wheel that the bearings seem to be ordinary sealed ball bearings mounted right inside the water chamber with no additional seals and no means of lubrication. That surely will be a problem very soon.

          I am afraid there are quite a few things to do before this one works properly .

          Best regards.

          Thor.

          --- In microhydro@yahoogroups.com, "Nando" <nando37@...> wrote:
          >
          > Thor :
          >
          > The ELC is a common PWM voltage regulator in reverse mode, this means that it is reading the rectified output voltage and if is higher than the reference starts to PWM modulate the power resistor to bring the voltage down via 50 HZ phase loading.
          >
          > This regulator is poor, the TL494 is the equivalent to the SG3825 family and has a wrong use.
          >
          > The TL494 has two amplifiers, one defined for current detection that can be used to detect the Zero crossing but due to the oscillator circuit the detector requires a clamp to limit the behavior of the oscillator lower transitional and keep the saw tooth working properly, and the second amplifier to detect the voltage fluctuations to turn ON the output pulse for the TRIAC ON position in the 180 degrees angle of the sine wave.
          >
          > This design is better for a Vdc control and I may wonder if the TRIAC is not a TRIAC but a MosFet -- does the device have a heat sink dissipator ?. Can you read the voltage that triggers the device to see if it is 12 volts with a width time equal to less than 180 degrees or around 2 or 3 volts ( if it is a TRIAC).
          >
          > The ELC in this case would have been better using two 555 IC, one as a Cero crossing point trigger with the time constant varied by the rectified voltage to trigger the second 555 to give a 30 or so microseconds pulse to turn the Triac ON phase wise, from the 180 degrees backwards incremented. -- This I did shortly after the 555 appeared in the market converting an equivalent circuit using a lot of discrete parts .
          >
          > Basically the ELC needs a cero crossing detector to trigger or reset an saw tooth oscillator with the amplitude of the saw tooth varied by the variable AC voltage ( rectified and slightly filtered) to cross the upper trigger point prior the reaching of the 50 Hz ( 20 ms) 180 degrees crossing to trigger the second 555 to generate the 30 or so microseconds to trigger the triac.
          >
          > We also need an amplifier to be able to modulate the saw tooth against a voltage reference.
          >
          > There is a need of a good motor Running Capacitor , connected in parallel to the generator ) to reduce the sine wave distortion that the TRIAC ON pulses generate.
          >
          > The head needed is defined by the PCD diameter of the turbine and the frequency to give the peripheral velocity of the turbine.
          >
          > The dynamic pressure drops too much !!
          >
          > The 40 meters 84 mm diameter is presenting too much water friction !! The 1 meter long 70 mm diameter is reducing the water volume too much !!
          >
          > To determine the HEAD
          >
          > So for a 1500 RPM turbine the RPS is 1500/60 sec = 25 RPS
          >
          > H= Head
          >
          > 25 RPS * pi * Diameter turbine
          >
          > 25 * 3.14 * 0.19 = 14,92 m/s
          >
          > Vjet = 100/49* 14,92= 30,45 m/s
          >
          > 30,45 ^2 = 2 * 9,81 * H where H = 47,27m/s Which is close to the reported : about 50 meters static ,
          >
          > For a 3 KW the ELC should control two - 1 KW full ON/OFF loads plus the primary phase controlled 1 KW load as a minimum for best operation, though I would make the ELC differently and in this case a primary phase loaded 500 watts, a second full ON/OFF 500 watts , then 2 - 1 KW each load to have a full complement loading , this if the maximum power is 3 KW, though I would suggest the last 1 KW load to be a 1,5 KW load in case that the generator can produce more than 3 KW.
          >
          > Nando
          >
          > ----- Original Message -----
          > From: Thor
          > To: microhydro@yahoogroups.com
          > Sent: Tuesday, July 31, 2012 16:51
          > Subject: [microhydro] Does Someone know this Turbine-Generator-ELC ??
          >
          >
          >
          > Hi everybody.
          >
          > First I was only going to ask if anybody had seen the ELC in the pictures I posted, but then decided to tell the full story as I far as I know it.
          >
          > I have been asked for help to get this Micro Hydro setup running properly. It was ordered and installed last year but so far almost nothing has worked as expected.
          >
          > Today I visited the site and took some pictures and measurements, (see group photos, album China-Turbine-In-Iceland http://groups.yahoo.com/group/microhydro/photos/album/1255983797/pic/list.
          >
          > The total head is approx. 50m, the static pressure with no flow is 4.8bar which drops to 3.0 bar at maximum needle valve opening.
          >
          > There is plenty of water, the pipe is always full.
          >
          > I was told the upper part of the penstock is 200m long HDPE pipe 110/6mm (internal dia. 108mm)
          > The lower part is 40m long HDPE 90/8mm (internal dia. 84mm)
          > there is also a short (1m long, less than 70mm dia.?) steel pipe where the penstock connects to the turbine.
          >
          > They ordered and got a turbine/generator rated for 50Hz/230V/3kW, 1500rpm at 40m head. It was known that the pipe would limit the flow and they did expect to run at approx. 80% pressure.
          >
          > First problem: The turbine did not come with a needle valve, just a far too wide fixed nozzle, so the owners made one, rather difficult to turn, but does not leak and seems to work all right.
          >
          > Second problem: slip ring damage.
          > The generator is single phase with 2 slip rings and 2 brushes on each ring. The brush holders are made from thin sheet metal, the brushes are very loose and originally they were positioned some 15-20mm away from the rings so the brushes got stuck in the holders with arcing and ring damage. The rings have been repaired and the position of brush holders has been fixed somewhat, but it is still not good.
          >
          > Third problem: The ELC has never worked properly. It has a single 3kW dump load controlled by a TRIAC. It senses the voltage and fortunately the generator seems properly made to give 220-230V at 50Hz.
          > But the ELC does not work smoothly, it either diverts no power to the dump load or far too much so the voltage and speed are just fluctuating wildly 170-240V 40-55Hz. The ELC has IC TL494CN which controls the TRIAC via MOC3020 Optocoupler. The TRIAC is unknown. The manufacturer used grinder on all the markings but failed to delete the IC´s :-)
          >
          > Fourth problem: The power output is much lower than expected, it seems to be at maximum running at 3.6bar pressure but then it is only approx. 5.6A x 230V = 1.3kW
          > We measured the last one at 50Hz, it is a bit more if we lower speed and voltage, 40Hz 170V 12.1A = 2.1kW
          >
          > By measuring the distance from nozzle to shaft it looks like effective diameter of wheel is approx. 190mm. I think that is a bit too big for 1500rpm at 40m head.
          >
          > Any information regarding this appreciated.
          >
          > Best regards.
          >
          > Thor.
          > (Electronics technician and a long time lurker in this group)
          >
          >
          >
          >
          >
          > [Non-text portions of this message have been removed]
          >
        • Nando
          Thor: I am having problems with my computer to calculate the flow parameters using the data you are supplying basically the power available is the Vjet
          Message 4 of 15 , Aug 2, 2012
          • 0 Attachment
            Thor:

            I am having problems with my computer to calculate the flow parameters using the data you are supplying basically the power available is the Vjet velocity times the area of the jet = volume of water being used

            I have used a turbine diameter of 19 cm as supplied by you and it may not be right but assuming right now as OK.

            In my previous message the Vjet = 30,45 m/s

            also Vjet = sq-root ( 2 * 9,81 * 40 meters head ) = 28,01 m/s -- The discrepancy here is due to the NO exact determination of the Head since it is assumed BY YOU .

            The peripheral velocity of the turbine is estimated as Vjet * 0.49 = 13,727 m/s

            Since you have a 50 HZ voltage frequency the RPS of the turbine is 1500 RPM/ 60 HZ = 25 RPS

            Therefore the Turbine diameter should be 13,727/ ( PI * Tdia) = 25 RPS

            Tdia =13,727/( 3,14 * 25 ) = 0.17477 m/s -- so there is a difference in the declared turbine diameter of 0,19 m/s versus the calculated diameter based this on the head of 40 meters

            To calculate the volume assuming that 3 Kw can be generated

            Power = Volume ( l/s) * Head (meter) * 9,81 * % assuming that 9,81 * % = 6

            3000 = Vol * 40 * 6 , where Vol = 3000/(40 * 6) = 12,5 liter/sec is required

            The head reduction due to the use of wrong pipe diameters can be determined by using some of the data

            40 HZ , 170 Volts and 2,1KW since this seems as the peak of the turbine then we can calculate the dynamic head of the system.

            Hz * 60 sec/#pole = RPM

            40 *60/2 = 1200 RPM

            The RPS = 1200/60 sec = 20

            Assuming that the turbine dia= 0,17477 then peripheral turbine velocity is : 0,17477 * 3,14 * 20 = 10,98 m/s

            Vjet = 100/49 * 10,98 = 22,408 m/s and the Vjet formula is " Sq-root ( 2 * 9,81 * Head)

            So Head = Vjet^2 /( 2 * 9,81) = 25,58 meter head

            The basic problem is the 40 meter of lower pipe diameter then 1 meter of even lower pipe diameter

            The turbine to produce 1500 RPM with a 17.477 cms diameter turbine requires around 36.5 net head but due to the bad installation of the wrong pipes the net head dropped to 25,58 meters.

            Let me know

            Nando





            ----- Original Message -----
            From: Nando
            To: microhydro@yahoogroups.com
            Sent: Wednesday, August 01, 2012 14:00
            Subject: Re: [microhydro] Does Someone know this Turbine-Generator-ELC ??



            Thor :

            The ELC is a common PWM voltage regulator in reverse mode, this means that it is reading the rectified output voltage and if is higher than the reference starts to PWM modulate the power resistor to bring the voltage down via 50 HZ phase loading.

            This regulator is poor, the TL494 is the equivalent to the SG3825 family and has a wrong use.

            The TL494 has two amplifiers, one defined for current detection that can be used to detect the Zero crossing but due to the oscillator circuit the detector requires a clamp to limit the behavior of the oscillator lower transitional and keep the saw tooth working properly, and the second amplifier to detect the voltage fluctuations to turn ON the output pulse for the TRIAC ON position in the 180 degrees angle of the sine wave.

            This design is better for a Vdc control and I may wonder if the TRIAC is not a TRIAC but a MosFet -- does the device have a heat sink dissipator ?. Can you read the voltage that triggers the device to see if it is 12 volts with a width time equal to less than 180 degrees or around 2 or 3 volts ( if it is a TRIAC).

            The ELC in this case would have been better using two 555 IC, one as a Cero crossing point trigger with the time constant varied by the rectified voltage to trigger the second 555 to give a 30 or so microseconds pulse to turn the Triac ON phase wise, from the 180 degrees backwards incremented. -- This I did shortly after the 555 appeared in the market converting an equivalent circuit using a lot of discrete parts .

            Basically the ELC needs a cero crossing detector to trigger or reset an saw tooth oscillator with the amplitude of the saw tooth varied by the variable AC voltage ( rectified and slightly filtered) to cross the upper trigger point prior the reaching of the 50 Hz ( 20 ms) 180 degrees crossing to trigger the second 555 to generate the 30 or so microseconds to trigger the triac.

            We also need an amplifier to be able to modulate the saw tooth against a voltage reference.

            There is a need of a good motor Running Capacitor , connected in parallel to the generator ) to reduce the sine wave distortion that the TRIAC ON pulses generate.

            The head needed is defined by the PCD diameter of the turbine and the frequency to give the peripheral velocity of the turbine.

            The dynamic pressure drops too much !!

            The 40 meters 84 mm diameter is presenting too much water friction !! The 1 meter long 70 mm diameter is reducing the water volume too much !!

            To determine the HEAD

            So for a 1500 RPM turbine the RPS is 1500/60 sec = 25 RPS

            H= Head

            25 RPS * pi * Diameter turbine

            25 * 3.14 * 0.19 = 14,92 m/s

            Vjet = 100/49* 14,92= 30,45 m/s

            30,45 ^2 = 2 * 9,81 * H where H = 47,27m/s Which is close to the reported : about 50 meters static ,

            For a 3 KW the ELC should control two - 1 KW full ON/OFF loads plus the primary phase controlled 1 KW load as a minimum for best operation, though I would make the ELC differently and in this case a primary phase loaded 500 watts, a second full ON/OFF 500 watts , then 2 - 1 KW each load to have a full complement loading , this if the maximum power is 3 KW, though I would suggest the last 1 KW load to be a 1,5 KW load in case that the generator can produce more than 3 KW.

            Nando

            ----- Original Message -----
            From: Thor
            To: microhydro@yahoogroups.com
            Sent: Tuesday, July 31, 2012 16:51
            Subject: [microhydro] Does Someone know this Turbine-Generator-ELC ??

            Hi everybody.

            First I was only going to ask if anybody had seen the ELC in the pictures I posted, but then decided to tell the full story as I far as I know it.

            I have been asked for help to get this Micro Hydro setup running properly. It was ordered and installed last year but so far almost nothing has worked as expected.

            Today I visited the site and took some pictures and measurements, (see group photos, album China-Turbine-In-Iceland http://groups.yahoo.com/group/microhydro/photos/album/1255983797/pic/list.

            The total head is approx. 50m, the static pressure with no flow is 4.8bar which drops to 3.0 bar at maximum needle valve opening.

            There is plenty of water, the pipe is always full.

            I was told the upper part of the penstock is 200m long HDPE pipe 110/6mm (internal dia. 108mm)
            The lower part is 40m long HDPE 90/8mm (internal dia. 84mm)
            there is also a short (1m long, less than 70mm dia.?) steel pipe where the penstock connects to the turbine.

            They ordered and got a turbine/generator rated for 50Hz/230V/3kW, 1500rpm at 40m head. It was known that the pipe would limit the flow and they did expect to run at approx. 80% pressure.

            First problem: The turbine did not come with a needle valve, just a far too wide fixed nozzle, so the owners made one, rather difficult to turn, but does not leak and seems to work all right.

            Second problem: slip ring damage.
            The generator is single phase with 2 slip rings and 2 brushes on each ring. The brush holders are made from thin sheet metal, the brushes are very loose and originally they were positioned some 15-20mm away from the rings so the brushes got stuck in the holders with arcing and ring damage. The rings have been repaired and the position of brush holders has been fixed somewhat, but it is still not good.

            Third problem: The ELC has never worked properly. It has a single 3kW dump load controlled by a TRIAC. It senses the voltage and fortunately the generator seems properly made to give 220-230V at 50Hz.
            But the ELC does not work smoothly, it either diverts no power to the dump load or far too much so the voltage and speed are just fluctuating wildly 170-240V 40-55Hz. The ELC has IC TL494CN which controls the TRIAC via MOC3020 Optocoupler. The TRIAC is unknown. The manufacturer used grinder on all the markings but failed to delete the IC´s :-)

            Fourth problem: The power output is much lower than expected, it seems to be at maximum running at 3.6bar pressure but then it is only approx. 5.6A x 230V = 1.3kW
            We measured the last one at 50Hz, it is a bit more if we lower speed and voltage, 40Hz 170V 12.1A = 2.1kW

            By measuring the distance from nozzle to shaft it looks like effective diameter of wheel is approx. 190mm. I think that is a bit too big for 1500rpm at 40m head.

            Any information regarding this appreciated.

            Best regards.

            Thor.
            (Electronics technician and a long time lurker in this group)

            [Non-text portions of this message have been removed]





            [Non-text portions of this message have been removed]
          • Nando
            THOR: You got the rest of the analysis and the idea of your ELC is not practical The ELC with 15 loads, you just need for easy control of 3 KW , to have 6
            Message 5 of 15 , Aug 2, 2012
            • 0 Attachment
              THOR:

              You got the rest of the analysis and the idea of your ELC is not practical

              The ELC with 15 loads, you just need for easy control of 3 KW , to have 6 loads of 500 watts and the one used as Phase control to be also 500 watts -- it is an error to use a double load there .

              Also use a 10 microfarad motor RUNNING CAPACITOR in parallel with the power lines to reduce the Triac variable phase On pulses distortion it generates,

              Do not use lamps as active ballast loads it is expensive if the lamps blow.

              I have not tried to calculate the nozzle diameter because the information has too many errors and it is a waste of time to define what the nozzle is, though we could calculate the water volume to produce 3 KW with a well defined head which you do not have due to the bad pipes installed.

              Assuming you have a net 45 meter head and 3 KW the water volume would be 3000= 45 *6 * Vol ; Vol= 11.1 liter/sec

              Vjet = Sq-rt( 2 * 9,81 * 45) = 29,71,4 m/s = 2971,4 cms/sc

              Jet Area = 11100/ 2971,4 = 3,7356 cms^2

              Jet dia = 2* Sq-rt ( 3,7356/3.14) = 2,18 cms diameter

              Nando



              ----- Original Message -----
              From: Thor
              To: microhydro@yahoogroups.com
              Sent: Thursday, August 02, 2012 08:12
              Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??





              Nando.

              Many thanks for your detailed reply.

              The ELC is all wrong as you said, I traced the PCB, drew a schematic with ExpressPCB and uploaded a GIF image of the result in the photos, must remember to put a strong warning there so nobody thinks it is good and tries to make one!!

              I can not see it detects zero crossing at all, only the rectified DC-supply voltage to the ELC itself.

              The big load switching semiconductor is a TRIAC, infinite resistance between MT1 and MT2 both ways and approx. 100ohms gate to MT1. The MOC3020 is an instant switching Opto-TRIAC.

              I have one or two old ELCs I once made lying around, they were originally designed for a bit more power, 10-30kW, have 15 fixed zero switching ON/OFF loads and one variable phase controlled load which was 2x bigger than the fixed loads.

              The fixed loads turn on one by one (count up) if the variable load is at more than 75% and they turn off (count down) if the variable load is less than 25%.

              In this case it should be enough to have 4x500W fixed loads and one 1000W variable. (Of course it would be fun to mount 15x200W old light bulbs in a row as loads and and have two parallel bulbs as the variable. Unfortunately that would not last long enough !!)

              The pipe is another problem, the turbine maker put a 2" pipe thread on the input so that explains the very narrow short section at the turbine.

              The jet diameter is unknown to me, from the picture I took it looks like it may be about 30mm. Is that all right ?

              Then there is the wheel, it somehow does not look quite right, the Hartvigsen Hydro spoons look so much better :-)

              I also noticed in the picture of the wheel that the bearings seem to be ordinary sealed ball bearings mounted right inside the water chamber with no additional seals and no means of lubrication. That surely will be a problem very soon.

              I am afraid there are quite a few things to do before this one works properly .

              Best regards.

              Thor.

              --- In microhydro@yahoogroups.com, "Nando" <nando37@...> wrote:
              >
              > Thor :
              >
              > The ELC is a common PWM voltage regulator in reverse mode, this means that it is reading the rectified output voltage and if is higher than the reference starts to PWM modulate the power resistor to bring the voltage down via 50 HZ phase loading.
              >
              > This regulator is poor, the TL494 is the equivalent to the SG3825 family and has a wrong use.
              >
              > The TL494 has two amplifiers, one defined for current detection that can be used to detect the Zero crossing but due to the oscillator circuit the detector requires a clamp to limit the behavior of the oscillator lower transitional and keep the saw tooth working properly, and the second amplifier to detect the voltage fluctuations to turn ON the output pulse for the TRIAC ON position in the 180 degrees angle of the sine wave.
              >
              > This design is better for a Vdc control and I may wonder if the TRIAC is not a TRIAC but a MosFet -- does the device have a heat sink dissipator ?. Can you read the voltage that triggers the device to see if it is 12 volts with a width time equal to less than 180 degrees or around 2 or 3 volts ( if it is a TRIAC).
              >
              > The ELC in this case would have been better using two 555 IC, one as a Cero crossing point trigger with the time constant varied by the rectified voltage to trigger the second 555 to give a 30 or so microseconds pulse to turn the Triac ON phase wise, from the 180 degrees backwards incremented. -- This I did shortly after the 555 appeared in the market converting an equivalent circuit using a lot of discrete parts .
              >
              > Basically the ELC needs a cero crossing detector to trigger or reset an saw tooth oscillator with the amplitude of the saw tooth varied by the variable AC voltage ( rectified and slightly filtered) to cross the upper trigger point prior the reaching of the 50 Hz ( 20 ms) 180 degrees crossing to trigger the second 555 to generate the 30 or so microseconds to trigger the triac.
              >
              > We also need an amplifier to be able to modulate the saw tooth against a voltage reference.
              >
              > There is a need of a good motor Running Capacitor , connected in parallel to the generator ) to reduce the sine wave distortion that the TRIAC ON pulses generate.
              >
              > The head needed is defined by the PCD diameter of the turbine and the frequency to give the peripheral velocity of the turbine.
              >
              > The dynamic pressure drops too much !!
              >
              > The 40 meters 84 mm diameter is presenting too much water friction !! The 1 meter long 70 mm diameter is reducing the water volume too much !!
              >
              > To determine the HEAD
              >
              > So for a 1500 RPM turbine the RPS is 1500/60 sec = 25 RPS
              >
              > H= Head
              >
              > 25 RPS * pi * Diameter turbine
              >
              > 25 * 3.14 * 0.19 = 14,92 m/s
              >
              > Vjet = 100/49* 14,92= 30,45 m/s
              >
              > 30,45 ^2 = 2 * 9,81 * H where H = 47,27m/s Which is close to the reported : about 50 meters static ,
              >
              > For a 3 KW the ELC should control two - 1 KW full ON/OFF loads plus the primary phase controlled 1 KW load as a minimum for best operation, though I would make the ELC differently and in this case a primary phase loaded 500 watts, a second full ON/OFF 500 watts , then 2 - 1 KW each load to have a full complement loading , this if the maximum power is 3 KW, though I would suggest the last 1 KW load to be a 1,5 KW load in case that the generator can produce more than 3 KW.
              >
              > Nando
              >
              > ----- Original Message -----
              > From: Thor
              > To: microhydro@yahoogroups.com
              > Sent: Tuesday, July 31, 2012 16:51
              > Subject: [microhydro] Does Someone know this Turbine-Generator-ELC ??
              >
              >
              >
              > Hi everybody.
              >
              > First I was only going to ask if anybody had seen the ELC in the pictures I posted, but then decided to tell the full story as I far as I know it.
              >
              > I have been asked for help to get this Micro Hydro setup running properly. It was ordered and installed last year but so far almost nothing has worked as expected.
              >
              > Today I visited the site and took some pictures and measurements, (see group photos, album China-Turbine-In-Iceland http://groups.yahoo.com/group/microhydro/photos/album/1255983797/pic/list.
              >
              > The total head is approx. 50m, the static pressure with no flow is 4.8bar which drops to 3.0 bar at maximum needle valve opening.
              >
              > There is plenty of water, the pipe is always full.
              >
              > I was told the upper part of the penstock is 200m long HDPE pipe 110/6mm (internal dia. 108mm)
              > The lower part is 40m long HDPE 90/8mm (internal dia. 84mm)
              > there is also a short (1m long, less than 70mm dia.?) steel pipe where the penstock connects to the turbine.
              >
              > They ordered and got a turbine/generator rated for 50Hz/230V/3kW, 1500rpm at 40m head. It was known that the pipe would limit the flow and they did expect to run at approx. 80% pressure.
              >
              > First problem: The turbine did not come with a needle valve, just a far too wide fixed nozzle, so the owners made one, rather difficult to turn, but does not leak and seems to work all right.
              >
              > Second problem: slip ring damage.
              > The generator is single phase with 2 slip rings and 2 brushes on each ring. The brush holders are made from thin sheet metal, the brushes are very loose and originally they were positioned some 15-20mm away from the rings so the brushes got stuck in the holders with arcing and ring damage. The rings have been repaired and the position of brush holders has been fixed somewhat, but it is still not good.
              >
              > Third problem: The ELC has never worked properly. It has a single 3kW dump load controlled by a TRIAC. It senses the voltage and fortunately the generator seems properly made to give 220-230V at 50Hz.
              > But the ELC does not work smoothly, it either diverts no power to the dump load or far too much so the voltage and speed are just fluctuating wildly 170-240V 40-55Hz. The ELC has IC TL494CN which controls the TRIAC via MOC3020 Optocoupler. The TRIAC is unknown. The manufacturer used grinder on all the markings but failed to delete the IC´s :-)
              >
              > Fourth problem: The power output is much lower than expected, it seems to be at maximum running at 3.6bar pressure but then it is only approx. 5.6A x 230V = 1.3kW
              > We measured the last one at 50Hz, it is a bit more if we lower speed and voltage, 40Hz 170V 12.1A = 2.1kW
              >
              > By measuring the distance from nozzle to shaft it looks like effective diameter of wheel is approx. 190mm. I think that is a bit too big for 1500rpm at 40m head.
              >
              > Any information regarding this appreciated.
              >
              > Best regards.
              >
              > Thor.
              > (Electronics technician and a long time lurker in this group)
              >
              >
              >
              >
              >
              > [Non-text portions of this message have been removed]
              >





              [Non-text portions of this message have been removed]
            • Thor
              Nando. It is possible to use the old ELC I made with any number of loads (15 is just the maximum), in this case 6x500W loads should work just fine. The ELC was
              Message 6 of 15 , Aug 3, 2012
              • 0 Attachment
                Nando.

                It is possible to use the old ELC I made with any number of loads (15 is just the maximum), in this case 6x500W loads should work just fine.

                The ELC was designed 25 years ago with discrete CMOS logic, the reason for the double size load is that the 0-180° phase load control became unstable near the 0° and 180° ends (some error in my design). By using a bigger variable load it was possible to stay away from the endpoints most of the time. Of course it would have been more elegant to fix the original stability problem, I spent quite some time trying that, but did not find a satisfactory solution at the time.

                The lightbulb idea was meant as a joke, I just visualized a kind of a power meter bar with all those bulbs in a row :-)

                Next time I visit this site we will install the ELC and also try to measure the power, water pressure and volume directly and accurately at various flow and rpm.

                Until we have a better measurements we are just wandering in circles in the fog.

                Best regards.

                Thor.

                --- In microhydro@yahoogroups.com, "Nando" <nando37@...> wrote:
                >
                > THOR:
                >
                > You got the rest of the analysis and the idea of your ELC is not practical
                >
                > The ELC with 15 loads, you just need for easy control of 3 KW , to have 6 loads of 500 watts and the one used as Phase control to be also 500 watts -- it is an error to use a double load there .
                >
                > Also use a 10 microfarad motor RUNNING CAPACITOR in parallel with the power lines to reduce the Triac variable phase On pulses distortion it generates,
                >
                > Do not use lamps as active ballast loads it is expensive if the lamps blow.
                >
                > I have not tried to calculate the nozzle diameter because the information has too many errors and it is a waste of time to define what the nozzle is, though we could calculate the water volume to produce 3 KW with a well defined head which you do not have due to the bad pipes installed.
                >
                > Assuming you have a net 45 meter head and 3 KW the water volume would be 3000= 45 *6 * Vol ; Vol= 11.1 liter/sec
                >
                > Vjet = Sq-rt( 2 * 9,81 * 45) = 29,71,4 m/s = 2971,4 cms/sc
                >
                > Jet Area = 11100/ 2971,4 = 3,7356 cms^2
                >
                > Jet dia = 2* Sq-rt ( 3,7356/3.14) = 2,18 cms diameter
                >
                > Nando
                >
                >
                >
                > ----- Original Message -----
                > From: Thor
                > To: microhydro@yahoogroups.com
                > Sent: Thursday, August 02, 2012 08:12
                > Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??
                >
                >
                >
                >
                >
                > Nando.
                >
                > Many thanks for your detailed reply.
                >
                > The ELC is all wrong as you said, I traced the PCB, drew a schematic with ExpressPCB and uploaded a GIF image of the result in the photos, must remember to put a strong warning there so nobody thinks it is good and tries to make one!!
                >
                > I can not see it detects zero crossing at all, only the rectified DC-supply voltage to the ELC itself.
                >
                > The big load switching semiconductor is a TRIAC, infinite resistance between MT1 and MT2 both ways and approx. 100ohms gate to MT1. The MOC3020 is an instant switching Opto-TRIAC.
                >
                > I have one or two old ELCs I once made lying around, they were originally designed for a bit more power, 10-30kW, have 15 fixed zero switching ON/OFF loads and one variable phase controlled load which was 2x bigger than the fixed loads.
                >
                > The fixed loads turn on one by one (count up) if the variable load is at more than 75% and they turn off (count down) if the variable load is less than 25%.
                >
                > In this case it should be enough to have 4x500W fixed loads and one 1000W variable. (Of course it would be fun to mount 15x200W old light bulbs in a row as loads and and have two parallel bulbs as the variable. Unfortunately that would not last long enough !!)
                >
                > The pipe is another problem, the turbine maker put a 2" pipe thread on the input so that explains the very narrow short section at the turbine.
                >
                > The jet diameter is unknown to me, from the picture I took it looks like it may be about 30mm. Is that all right ?
                >
                > Then there is the wheel, it somehow does not look quite right, the Hartvigsen Hydro spoons look so much better :-)
                >
                > I also noticed in the picture of the wheel that the bearings seem to be ordinary sealed ball bearings mounted right inside the water chamber with no additional seals and no means of lubrication. That surely will be a problem very soon.
                >
                > I am afraid there are quite a few things to do before this one works properly .
                >
                > Best regards.
                >
                > Thor.
                >
                > --- In microhydro@yahoogroups.com, "Nando" <nando37@> wrote:
                > >
                > > Thor :
                > >
                > > The ELC is a common PWM voltage regulator in reverse mode, this means that it is reading the rectified output voltage and if is higher than the reference starts to PWM modulate the power resistor to bring the voltage down via 50 HZ phase loading.
                > >
                > > This regulator is poor, the TL494 is the equivalent to the SG3825 family and has a wrong use.
                > >
                > > The TL494 has two amplifiers, one defined for current detection that can be used to detect the Zero crossing but due to the oscillator circuit the detector requires a clamp to limit the behavior of the oscillator lower transitional and keep the saw tooth working properly, and the second amplifier to detect the voltage fluctuations to turn ON the output pulse for the TRIAC ON position in the 180 degrees angle of the sine wave.
                > >
                > > This design is better for a Vdc control and I may wonder if the TRIAC is not a TRIAC but a MosFet -- does the device have a heat sink dissipator ?. Can you read the voltage that triggers the device to see if it is 12 volts with a width time equal to less than 180 degrees or around 2 or 3 volts ( if it is a TRIAC).
                > >
                > > The ELC in this case would have been better using two 555 IC, one as a Cero crossing point trigger with the time constant varied by the rectified voltage to trigger the second 555 to give a 30 or so microseconds pulse to turn the Triac ON phase wise, from the 180 degrees backwards incremented. -- This I did shortly after the 555 appeared in the market converting an equivalent circuit using a lot of discrete parts .
                > >
                > > Basically the ELC needs a cero crossing detector to trigger or reset an saw tooth oscillator with the amplitude of the saw tooth varied by the variable AC voltage ( rectified and slightly filtered) to cross the upper trigger point prior the reaching of the 50 Hz ( 20 ms) 180 degrees crossing to trigger the second 555 to generate the 30 or so microseconds to trigger the triac.
                > >
                > > We also need an amplifier to be able to modulate the saw tooth against a voltage reference.
                > >
                > > There is a need of a good motor Running Capacitor , connected in parallel to the generator ) to reduce the sine wave distortion that the TRIAC ON pulses generate.
                > >
                > > The head needed is defined by the PCD diameter of the turbine and the frequency to give the peripheral velocity of the turbine.
                > >
                > > The dynamic pressure drops too much !!
                > >
                > > The 40 meters 84 mm diameter is presenting too much water friction !! The 1 meter long 70 mm diameter is reducing the water volume too much !!
                > >
                > > To determine the HEAD
                > >
                > > So for a 1500 RPM turbine the RPS is 1500/60 sec = 25 RPS
                > >
                > > H= Head
                > >
                > > 25 RPS * pi * Diameter turbine
                > >
                > > 25 * 3.14 * 0.19 = 14,92 m/s
                > >
                > > Vjet = 100/49* 14,92= 30,45 m/s
                > >
                > > 30,45 ^2 = 2 * 9,81 * H where H = 47,27m/s Which is close to the reported : about 50 meters static ,
                > >
                > > For a 3 KW the ELC should control two - 1 KW full ON/OFF loads plus the primary phase controlled 1 KW load as a minimum for best operation, though I would make the ELC differently and in this case a primary phase loaded 500 watts, a second full ON/OFF 500 watts , then 2 - 1 KW each load to have a full complement loading , this if the maximum power is 3 KW, though I would suggest the last 1 KW load to be a 1,5 KW load in case that the generator can produce more than 3 KW.
                > >
                > > Nando
                > >
                > > ----- Original Message -----
                > > From: Thor
                > > To: microhydro@yahoogroups.com
                > > Sent: Tuesday, July 31, 2012 16:51
                > > Subject: [microhydro] Does Someone know this Turbine-Generator-ELC ??
                > >
                > >
                > >
                > > Hi everybody.
                > >
                > > First I was only going to ask if anybody had seen the ELC in the pictures I posted, but then decided to tell the full story as I far as I know it.
                > >
                > > I have been asked for help to get this Micro Hydro setup running properly. It was ordered and installed last year but so far almost nothing has worked as expected.
                > >
                > > Today I visited the site and took some pictures and measurements, (see group photos, album China-Turbine-In-Iceland http://groups.yahoo.com/group/microhydro/photos/album/1255983797/pic/list.
                > >
                > > The total head is approx. 50m, the static pressure with no flow is 4.8bar which drops to 3.0 bar at maximum needle valve opening.
                > >
                > > There is plenty of water, the pipe is always full.
                > >
                > > I was told the upper part of the penstock is 200m long HDPE pipe 110/6mm (internal dia. 108mm)
                > > The lower part is 40m long HDPE 90/8mm (internal dia. 84mm)
                > > there is also a short (1m long, less than 70mm dia.?) steel pipe where the penstock connects to the turbine.
                > >
                > > They ordered and got a turbine/generator rated for 50Hz/230V/3kW, 1500rpm at 40m head. It was known that the pipe would limit the flow and they did expect to run at approx. 80% pressure.
                > >
                > > First problem: The turbine did not come with a needle valve, just a far too wide fixed nozzle, so the owners made one, rather difficult to turn, but does not leak and seems to work all right.
                > >
                > > Second problem: slip ring damage.
                > > The generator is single phase with 2 slip rings and 2 brushes on each ring. The brush holders are made from thin sheet metal, the brushes are very loose and originally they were positioned some 15-20mm away from the rings so the brushes got stuck in the holders with arcing and ring damage. The rings have been repaired and the position of brush holders has been fixed somewhat, but it is still not good.
                > >
                > > Third problem: The ELC has never worked properly. It has a single 3kW dump load controlled by a TRIAC. It senses the voltage and fortunately the generator seems properly made to give 220-230V at 50Hz.
                > > But the ELC does not work smoothly, it either diverts no power to the dump load or far too much so the voltage and speed are just fluctuating wildly 170-240V 40-55Hz. The ELC has IC TL494CN which controls the TRIAC via MOC3020 Optocoupler. The TRIAC is unknown. The manufacturer used grinder on all the markings but failed to delete the IC´s :-)
                > >
                > > Fourth problem: The power output is much lower than expected, it seems to be at maximum running at 3.6bar pressure but then it is only approx. 5.6A x 230V = 1.3kW
                > > We measured the last one at 50Hz, it is a bit more if we lower speed and voltage, 40Hz 170V 12.1A = 2.1kW
                > >
                > > By measuring the distance from nozzle to shaft it looks like effective diameter of wheel is approx. 190mm. I think that is a bit too big for 1500rpm at 40m head.
                > >
                > > Any information regarding this appreciated.
                > >
                > > Best regards.
                > >
                > > Thor.
                > > (Electronics technician and a long time lurker in this group)
                > >
                > >
                > >
                > >
                > >
                > > [Non-text portions of this message have been removed]
                > >
                >
                >
                >
                >
                >
                > [Non-text portions of this message have been removed]
                >
              • Michael
                Hello, in relation to the controller, which you guys say doesnt work: My question is, is the concept viable? In the schematic Thor has drawn, the generator
                Message 7 of 15 , Aug 3, 2012
                • 0 Attachment
                  Hello,
                  in relation to the controller, which you guys say doesnt work:
                  My question is,
                  is the concept viable? In the schematic Thor has drawn, the generator voltage is the feedback input to the PWM ic, so they are attempting to regulate the generator voltage. Done properly would it work, i.e to use a PWM chip to control the load on a generator to keep the generator voltage constant? For example if the voltage was rectified to DC, and smoothed, could the PWM output switch on a load, and control load.

                  Michael.




                  --- In microhydro@yahoogroups.com, "Nando" <nando37@...> wrote:
                  >
                  > THOR:
                  >
                  > You got the rest of the analysis and the idea of your ELC is not practical
                  >
                  > The ELC with 15 loads, you just need for easy control of 3 KW , to have 6 loads of 500 watts and the one used as Phase control to be also 500 watts -- it is an error to use a double load there .
                  >
                  > Also use a 10 microfarad motor RUNNING CAPACITOR in parallel with the power lines to reduce the Triac variable phase On pulses distortion it generates,
                  >
                  > Do not use lamps as active ballast loads it is expensive if the lamps blow.
                  >
                  > I have not tried to calculate the nozzle diameter because the information has too many errors and it is a waste of time to define what the nozzle is, though we could calculate the water volume to produce 3 KW with a well defined head which you do not have due to the bad pipes installed.
                  >
                  > Assuming you have a net 45 meter head and 3 KW the water volume would be 3000= 45 *6 * Vol ; Vol= 11.1 liter/sec
                  >
                  > Vjet = Sq-rt( 2 * 9,81 * 45) = 29,71,4 m/s = 2971,4 cms/sc
                  >
                  > Jet Area = 11100/ 2971,4 = 3,7356 cms^2
                  >
                  > Jet dia = 2* Sq-rt ( 3,7356/3.14) = 2,18 cms diameter
                  >
                  > Nando
                  >
                  >
                  >
                  > ----- Original Message -----
                  > From: Thor
                  > To: microhydro@yahoogroups.com
                  > Sent: Thursday, August 02, 2012 08:12
                  > Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??
                  >
                  >
                  >
                  >
                  >
                  > Nando.
                  >
                  > Many thanks for your detailed reply.
                  >
                  > The ELC is all wrong as you said, I traced the PCB, drew a schematic with ExpressPCB and uploaded a GIF image of the result in the photos, must remember to put a strong warning there so nobody thinks it is good and tries to make one!!
                  >
                  > I can not see it detects zero crossing at all, only the rectified DC-supply voltage to the ELC itself.
                  >
                  > The big load switching semiconductor is a TRIAC, infinite resistance between MT1 and MT2 both ways and approx. 100ohms gate to MT1. The MOC3020 is an instant switching Opto-TRIAC.
                  >
                  > I have one or two old ELCs I once made lying around, they were originally designed for a bit more power, 10-30kW, have 15 fixed zero switching ON/OFF loads and one variable phase controlled load which was 2x bigger than the fixed loads.
                  >
                  > The fixed loads turn on one by one (count up) if the variable load is at more than 75% and they turn off (count down) if the variable load is less than 25%.
                  >
                  > In this case it should be enough to have 4x500W fixed loads and one 1000W variable. (Of course it would be fun to mount 15x200W old light bulbs in a row as loads and and have two parallel bulbs as the variable. Unfortunately that would not last long enough !!)
                  >
                  > The pipe is another problem, the turbine maker put a 2" pipe thread on the input so that explains the very narrow short section at the turbine.
                  >
                  > The jet diameter is unknown to me, from the picture I took it looks like it may be about 30mm. Is that all right ?
                  >
                  > Then there is the wheel, it somehow does not look quite right, the Hartvigsen Hydro spoons look so much better :-)
                  >
                  > I also noticed in the picture of the wheel that the bearings seem to be ordinary sealed ball bearings mounted right inside the water chamber with no additional seals and no means of lubrication. That surely will be a problem very soon.
                  >
                  > I am afraid there are quite a few things to do before this one works properly .
                  >
                  > Best regards.
                  >
                  > Thor.
                  >
                  > --- In microhydro@yahoogroups.com, "Nando" <nando37@> wrote:
                  > >
                  > > Thor :
                  > >
                  > > The ELC is a common PWM voltage regulator in reverse mode, this means that it is reading the rectified output voltage and if is higher than the reference starts to PWM modulate the power resistor to bring the voltage down via 50 HZ phase loading.
                  > >
                  > > This regulator is poor, the TL494 is the equivalent to the SG3825 family and has a wrong use.
                  > >
                  > > The TL494 has two amplifiers, one defined for current detection that can be used to detect the Zero crossing but due to the oscillator circuit the detector requires a clamp to limit the behavior of the oscillator lower transitional and keep the saw tooth working properly, and the second amplifier to detect the voltage fluctuations to turn ON the output pulse for the TRIAC ON position in the 180 degrees angle of the sine wave.
                  > >
                  > > This design is better for a Vdc control and I may wonder if the TRIAC is not a TRIAC but a MosFet -- does the device have a heat sink dissipator ?. Can you read the voltage that triggers the device to see if it is 12 volts with a width time equal to less than 180 degrees or around 2 or 3 volts ( if it is a TRIAC).
                  > >
                  > > The ELC in this case would have been better using two 555 IC, one as a Cero crossing point trigger with the time constant varied by the rectified voltage to trigger the second 555 to give a 30 or so microseconds pulse to turn the Triac ON phase wise, from the 180 degrees backwards incremented. -- This I did shortly after the 555 appeared in the market converting an equivalent circuit using a lot of discrete parts .
                  > >
                  > > Basically the ELC needs a cero crossing detector to trigger or reset an saw tooth oscillator with the amplitude of the saw tooth varied by the variable AC voltage ( rectified and slightly filtered) to cross the upper trigger point prior the reaching of the 50 Hz ( 20 ms) 180 degrees crossing to trigger the second 555 to generate the 30 or so microseconds to trigger the triac.
                  > >
                  > > We also need an amplifier to be able to modulate the saw tooth against a voltage reference.
                  > >
                  > > There is a need of a good motor Running Capacitor , connected in parallel to the generator ) to reduce the sine wave distortion that the TRIAC ON pulses generate.
                  > >
                  > > The head needed is defined by the PCD diameter of the turbine and the frequency to give the peripheral velocity of the turbine.
                  > >
                  > > The dynamic pressure drops too much !!
                  > >
                  > > The 40 meters 84 mm diameter is presenting too much water friction !! The 1 meter long 70 mm diameter is reducing the water volume too much !!
                  > >
                  > > To determine the HEAD
                  > >
                  > > So for a 1500 RPM turbine the RPS is 1500/60 sec = 25 RPS
                  > >
                  > > H= Head
                  > >
                  > > 25 RPS * pi * Diameter turbine
                  > >
                  > > 25 * 3.14 * 0.19 = 14,92 m/s
                  > >
                  > > Vjet = 100/49* 14,92= 30,45 m/s
                  > >
                  > > 30,45 ^2 = 2 * 9,81 * H where H = 47,27m/s Which is close to the reported : about 50 meters static ,
                  > >
                  > > For a 3 KW the ELC should control two - 1 KW full ON/OFF loads plus the primary phase controlled 1 KW load as a minimum for best operation, though I would make the ELC differently and in this case a primary phase loaded 500 watts, a second full ON/OFF 500 watts , then 2 - 1 KW each load to have a full complement loading , this if the maximum power is 3 KW, though I would suggest the last 1 KW load to be a 1,5 KW load in case that the generator can produce more than 3 KW.
                  > >
                  > > Nando
                  > >
                  > > ----- Original Message -----
                  > > From: Thor
                  > > To: microhydro@yahoogroups.com
                  > > Sent: Tuesday, July 31, 2012 16:51
                  > > Subject: [microhydro] Does Someone know this Turbine-Generator-ELC ??
                  > >
                  > >
                  > >
                  > > Hi everybody.
                  > >
                  > > First I was only going to ask if anybody had seen the ELC in the pictures I posted, but then decided to tell the full story as I far as I know it.
                  > >
                  > > I have been asked for help to get this Micro Hydro setup running properly. It was ordered and installed last year but so far almost nothing has worked as expected.
                  > >
                  > > Today I visited the site and took some pictures and measurements, (see group photos, album China-Turbine-In-Iceland http://groups.yahoo.com/group/microhydro/photos/album/1255983797/pic/list.
                  > >
                  > > The total head is approx. 50m, the static pressure with no flow is 4.8bar which drops to 3.0 bar at maximum needle valve opening.
                  > >
                  > > There is plenty of water, the pipe is always full.
                  > >
                  > > I was told the upper part of the penstock is 200m long HDPE pipe 110/6mm (internal dia. 108mm)
                  > > The lower part is 40m long HDPE 90/8mm (internal dia. 84mm)
                  > > there is also a short (1m long, less than 70mm dia.?) steel pipe where the penstock connects to the turbine.
                  > >
                  > > They ordered and got a turbine/generator rated for 50Hz/230V/3kW, 1500rpm at 40m head. It was known that the pipe would limit the flow and they did expect to run at approx. 80% pressure.
                  > >
                  > > First problem: The turbine did not come with a needle valve, just a far too wide fixed nozzle, so the owners made one, rather difficult to turn, but does not leak and seems to work all right.
                  > >
                  > > Second problem: slip ring damage.
                  > > The generator is single phase with 2 slip rings and 2 brushes on each ring. The brush holders are made from thin sheet metal, the brushes are very loose and originally they were positioned some 15-20mm away from the rings so the brushes got stuck in the holders with arcing and ring damage. The rings have been repaired and the position of brush holders has been fixed somewhat, but it is still not good.
                  > >
                  > > Third problem: The ELC has never worked properly. It has a single 3kW dump load controlled by a TRIAC. It senses the voltage and fortunately the generator seems properly made to give 220-230V at 50Hz.
                  > > But the ELC does not work smoothly, it either diverts no power to the dump load or far too much so the voltage and speed are just fluctuating wildly 170-240V 40-55Hz. The ELC has IC TL494CN which controls the TRIAC via MOC3020 Optocoupler. The TRIAC is unknown. The manufacturer used grinder on all the markings but failed to delete the IC´s :-)
                  > >
                  > > Fourth problem: The power output is much lower than expected, it seems to be at maximum running at 3.6bar pressure but then it is only approx. 5.6A x 230V = 1.3kW
                  > > We measured the last one at 50Hz, it is a bit more if we lower speed and voltage, 40Hz 170V 12.1A = 2.1kW
                  > >
                  > > By measuring the distance from nozzle to shaft it looks like effective diameter of wheel is approx. 190mm. I think that is a bit too big for 1500rpm at 40m head.
                  > >
                  > > Any information regarding this appreciated.
                  > >
                  > > Best regards.
                  > >
                  > > Thor.
                  > > (Electronics technician and a long time lurker in this group)
                  > >
                  > >
                  > >
                  > >
                  > >
                  > > [Non-text portions of this message have been removed]
                  > >
                  >
                  >
                  >
                  >
                  >
                  > [Non-text portions of this message have been removed]
                  >
                • Nando
                  Thor: The instability is caused because the PWM is pulsing close to the Zero crossing, you need to have a Window comparator to stop the PWM during the +/- 20
                  Message 8 of 15 , Aug 3, 2012
                  • 0 Attachment
                    Thor:

                    The instability is caused because the PWM is pulsing close to the Zero crossing, you need to have a Window comparator to stop the PWM during the +/- 20 ( 20 to 30 ) degrees from Zero to make sure the Zero crossing is properly detected at the right time when the sine wave is clean -- also use that window comparator to let the Zero crossing to detect the Zero point .

                    Therefore no such problem will creep in

                    Nando

                    ----- Original Message -----
                    From: Thor
                    To: microhydro@yahoogroups.com
                    Sent: Friday, August 03, 2012 07:03
                    Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??





                    Nando.

                    It is possible to use the old ELC I made with any number of loads (15 is just the maximum), in this case 6x500W loads should work just fine.

                    The ELC was designed 25 years ago with discrete CMOS logic, the reason for the double size load is that the 0-180° phase load control became unstable near the 0° and 180° ends (some error in my design). By using a bigger variable load it was possible to stay away from the endpoints most of the time. Of course it would have been more elegant to fix the original stability problem, I spent quite some time trying that, but did not find a satisfactory solution at the time.

                    The lightbulb idea was meant as a joke, I just visualized a kind of a power meter bar with all those bulbs in a row :-)

                    Next time I visit this site we will install the ELC and also try to measure the power, water pressure and volume directly and accurately at various flow and rpm.

                    Until we have a better measurements we are just wandering in circles in the fog.

                    Best regards.

                    Thor.

                    --- In microhydro@yahoogroups.com, "Nando" <nando37@...> wrote:
                    >
                    > THOR:
                    >
                    > You got the rest of the analysis and the idea of your ELC is not practical
                    >
                    > The ELC with 15 loads, you just need for easy control of 3 KW , to have 6 loads of 500 watts and the one used as Phase control to be also 500 watts -- it is an error to use a double load there .
                    >
                    > Also use a 10 microfarad motor RUNNING CAPACITOR in parallel with the power lines to reduce the Triac variable phase On pulses distortion it generates,
                    >
                    > Do not use lamps as active ballast loads it is expensive if the lamps blow.
                    >
                    > I have not tried to calculate the nozzle diameter because the information has too many errors and it is a waste of time to define what the nozzle is, though we could calculate the water volume to produce 3 KW with a well defined head which you do not have due to the bad pipes installed.
                    >
                    > Assuming you have a net 45 meter head and 3 KW the water volume would be 3000= 45 *6 * Vol ; Vol= 11.1 liter/sec
                    >
                    > Vjet = Sq-rt( 2 * 9,81 * 45) = 29,71,4 m/s = 2971,4 cms/sc
                    >
                    > Jet Area = 11100/ 2971,4 = 3,7356 cms^2
                    >
                    > Jet dia = 2* Sq-rt ( 3,7356/3.14) = 2,18 cms diameter
                    >
                    > Nando
                    >
                    >
                    >
                    > ----- Original Message -----
                    > From: Thor
                    > To: microhydro@yahoogroups.com
                    > Sent: Thursday, August 02, 2012 08:12
                    > Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??
                    >
                    >
                    >
                    >
                    >
                    > Nando.
                    >
                    > Many thanks for your detailed reply.
                    >
                    > The ELC is all wrong as you said, I traced the PCB, drew a schematic with ExpressPCB and uploaded a GIF image of the result in the photos, must remember to put a strong warning there so nobody thinks it is good and tries to make one!!
                    >
                    > I can not see it detects zero crossing at all, only the rectified DC-supply voltage to the ELC itself.
                    >
                    > The big load switching semiconductor is a TRIAC, infinite resistance between MT1 and MT2 both ways and approx. 100ohms gate to MT1. The MOC3020 is an instant switching Opto-TRIAC.
                    >
                    > I have one or two old ELCs I once made lying around, they were originally designed for a bit more power, 10-30kW, have 15 fixed zero switching ON/OFF loads and one variable phase controlled load which was 2x bigger than the fixed loads.
                    >
                    > The fixed loads turn on one by one (count up) if the variable load is at more than 75% and they turn off (count down) if the variable load is less than 25%.
                    >
                    > In this case it should be enough to have 4x500W fixed loads and one 1000W variable. (Of course it would be fun to mount 15x200W old light bulbs in a row as loads and and have two parallel bulbs as the variable. Unfortunately that would not last long enough !!)
                    >
                    > The pipe is another problem, the turbine maker put a 2" pipe thread on the input so that explains the very narrow short section at the turbine.
                    >
                    > The jet diameter is unknown to me, from the picture I took it looks like it may be about 30mm. Is that all right ?
                    >
                    > Then there is the wheel, it somehow does not look quite right, the Hartvigsen Hydro spoons look so much better :-)
                    >
                    > I also noticed in the picture of the wheel that the bearings seem to be ordinary sealed ball bearings mounted right inside the water chamber with no additional seals and no means of lubrication. That surely will be a problem very soon.
                    >
                    > I am afraid there are quite a few things to do before this one works properly .
                    >
                    > Best regards.
                    >
                    > Thor.
                    >
                    > --- In microhydro@yahoogroups.com, "Nando" <nando37@> wrote:
                    > >
                    > > Thor :
                    > >
                    > > The ELC is a common PWM voltage regulator in reverse mode, this means that it is reading the rectified output voltage and if is higher than the reference starts to PWM modulate the power resistor to bring the voltage down via 50 HZ phase loading.
                    > >
                    > > This regulator is poor, the TL494 is the equivalent to the SG3825 family and has a wrong use.
                    > >
                    > > The TL494 has two amplifiers, one defined for current detection that can be used to detect the Zero crossing but due to the oscillator circuit the detector requires a clamp to limit the behavior of the oscillator lower transitional and keep the saw tooth working properly, and the second amplifier to detect the voltage fluctuations to turn ON the output pulse for the TRIAC ON position in the 180 degrees angle of the sine wave.
                    > >
                    > > This design is better for a Vdc control and I may wonder if the TRIAC is not a TRIAC but a MosFet -- does the device have a heat sink dissipator ?. Can you read the voltage that triggers the device to see if it is 12 volts with a width time equal to less than 180 degrees or around 2 or 3 volts ( if it is a TRIAC).
                    > >
                    > > The ELC in this case would have been better using two 555 IC, one as a Cero crossing point trigger with the time constant varied by the rectified voltage to trigger the second 555 to give a 30 or so microseconds pulse to turn the Triac ON phase wise, from the 180 degrees backwards incremented. -- This I did shortly after the 555 appeared in the market converting an equivalent circuit using a lot of discrete parts .
                    > >
                    > > Basically the ELC needs a cero crossing detector to trigger or reset an saw tooth oscillator with the amplitude of the saw tooth varied by the variable AC voltage ( rectified and slightly filtered) to cross the upper trigger point prior the reaching of the 50 Hz ( 20 ms) 180 degrees crossing to trigger the second 555 to generate the 30 or so microseconds to trigger the triac.
                    > >
                    > > We also need an amplifier to be able to modulate the saw tooth against a voltage reference.
                    > >
                    > > There is a need of a good motor Running Capacitor , connected in parallel to the generator ) to reduce the sine wave distortion that the TRIAC ON pulses generate.
                    > >
                    > > The head needed is defined by the PCD diameter of the turbine and the frequency to give the peripheral velocity of the turbine.
                    > >
                    > > The dynamic pressure drops too much !!
                    > >
                    > > The 40 meters 84 mm diameter is presenting too much water friction !! The 1 meter long 70 mm diameter is reducing the water volume too much !!
                    > >
                    > > To determine the HEAD
                    > >
                    > > So for a 1500 RPM turbine the RPS is 1500/60 sec = 25 RPS
                    > >
                    > > H= Head
                    > >
                    > > 25 RPS * pi * Diameter turbine
                    > >
                    > > 25 * 3.14 * 0.19 = 14,92 m/s
                    > >
                    > > Vjet = 100/49* 14,92= 30,45 m/s
                    > >
                    > > 30,45 ^2 = 2 * 9,81 * H where H = 47,27m/s Which is close to the reported : about 50 meters static ,
                    > >
                    > > For a 3 KW the ELC should control two - 1 KW full ON/OFF loads plus the primary phase controlled 1 KW load as a minimum for best operation, though I would make the ELC differently and in this case a primary phase loaded 500 watts, a second full ON/OFF 500 watts , then 2 - 1 KW each load to have a full complement loading , this if the maximum power is 3 KW, though I would suggest the last 1 KW load to be a 1,5 KW load in case that the generator can produce more than 3 KW.
                    > >
                    > > Nando
                    > >
                    > > ----- Original Message -----
                    > > From: Thor
                    > > To: microhydro@yahoogroups.com
                    > > Sent: Tuesday, July 31, 2012 16:51
                    > > Subject: [microhydro] Does Someone know this Turbine-Generator-ELC ??
                    > >
                    > >
                    > >
                    > > Hi everybody.
                    > >
                    > > First I was only going to ask if anybody had seen the ELC in the pictures I posted, but then decided to tell the full story as I far as I know it.
                    > >
                    > > I have been asked for help to get this Micro Hydro setup running properly. It was ordered and installed last year but so far almost nothing has worked as expected.
                    > >
                    > > Today I visited the site and took some pictures and measurements, (see group photos, album China-Turbine-In-Iceland http://groups.yahoo.com/group/microhydro/photos/album/1255983797/pic/list.
                    > >
                    > > The total head is approx. 50m, the static pressure with no flow is 4.8bar which drops to 3.0 bar at maximum needle valve opening.
                    > >
                    > > There is plenty of water, the pipe is always full.
                    > >
                    > > I was told the upper part of the penstock is 200m long HDPE pipe 110/6mm (internal dia. 108mm)
                    > > The lower part is 40m long HDPE 90/8mm (internal dia. 84mm)
                    > > there is also a short (1m long, less than 70mm dia.?) steel pipe where the penstock connects to the turbine.
                    > >
                    > > They ordered and got a turbine/generator rated for 50Hz/230V/3kW, 1500rpm at 40m head. It was known that the pipe would limit the flow and they did expect to run at approx. 80% pressure.
                    > >
                    > > First problem: The turbine did not come with a needle valve, just a far too wide fixed nozzle, so the owners made one, rather difficult to turn, but does not leak and seems to work all right.
                    > >
                    > > Second problem: slip ring damage.
                    > > The generator is single phase with 2 slip rings and 2 brushes on each ring. The brush holders are made from thin sheet metal, the brushes are very loose and originally they were positioned some 15-20mm away from the rings so the brushes got stuck in the holders with arcing and ring damage. The rings have been repaired and the position of brush holders has been fixed somewhat, but it is still not good.
                    > >
                    > > Third problem: The ELC has never worked properly. It has a single 3kW dump load controlled by a TRIAC. It senses the voltage and fortunately the generator seems properly made to give 220-230V at 50Hz.
                    > > But the ELC does not work smoothly, it either diverts no power to the dump load or far too much so the voltage and speed are just fluctuating wildly 170-240V 40-55Hz. The ELC has IC TL494CN which controls the TRIAC via MOC3020 Optocoupler. The TRIAC is unknown. The manufacturer used grinder on all the markings but failed to delete the IC´s :-)
                    > >
                    > > Fourth problem: The power output is much lower than expected, it seems to be at maximum running at 3.6bar pressure but then it is only approx. 5.6A x 230V = 1.3kW
                    > > We measured the last one at 50Hz, it is a bit more if we lower speed and voltage, 40Hz 170V 12.1A = 2.1kW
                    > >
                    > > By measuring the distance from nozzle to shaft it looks like effective diameter of wheel is approx. 190mm. I think that is a bit too big for 1500rpm at 40m head.
                    > >
                    > > Any information regarding this appreciated.
                    > >
                    > > Best regards.
                    > >
                    > > Thor.
                    > > (Electronics technician and a long time lurker in this group)
                    > >
                    > >
                    > >
                    > >
                    > >
                    > > [Non-text portions of this message have been removed]
                    > >
                    >
                    >
                    >
                    >
                    >
                    > [Non-text portions of this message have been removed]
                    >





                    [Non-text portions of this message have been removed]
                  • Nando
                    Michael: The circuit fails because it is using a Triac and the circuit if you examine it carefully will see that just a comparator is used and for that purpose
                    Message 9 of 15 , Aug 3, 2012
                    • 0 Attachment
                      Michael:

                      The circuit fails because it is using a Triac and the circuit if you examine it carefully will see that just a comparator is used and for that purpose a power Mosfet is needed and not a TRIAC plus a ballast load to load the generator to reduce the DC voltage depending on the time constant of the storage capacitor prior to the Voltage regulator ( 12 volts ) .

                      The circuit make work if the Triac is replaced with a high Voltage Mosfet with a ballast equal to close the peak power and the filter in the rectified circuit is set to have certain low voltage.

                      I have used this type of circuit to regulate induction motor as generators using the sine wave rectified with an independent time constant for the PWM to operate properly.

                      Nando

                      ----- Original Message -----
                      From: Michael
                      To: microhydro@yahoogroups.com
                      Sent: Friday, August 03, 2012 09:32
                      Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??



                      Hello,
                      in relation to the controller, which you guys say doesnt work:
                      My question is,
                      is the concept viable? In the schematic Thor has drawn, the generator voltage is the feedback input to the PWM ic, so they are attempting to regulate the generator voltage. Done properly would it work, i.e to use a PWM chip to control the load on a generator to keep the generator voltage constant? For example if the voltage was rectified to DC, and smoothed, could the PWM output switch on a load, and control load.

                      Michael.

                      --- In microhydro@yahoogroups.com, "Nando" <nando37@...> wrote:
                      >
                      > THOR:
                      >
                      > You got the rest of the analysis and the idea of your ELC is not practical
                      >
                      > The ELC with 15 loads, you just need for easy control of 3 KW , to have 6 loads of 500 watts and the one used as Phase control to be also 500 watts -- it is an error to use a double load there .
                      >
                      > Also use a 10 microfarad motor RUNNING CAPACITOR in parallel with the power lines to reduce the Triac variable phase On pulses distortion it generates,
                      >
                      > Do not use lamps as active ballast loads it is expensive if the lamps blow.
                      >
                      > I have not tried to calculate the nozzle diameter because the information has too many errors and it is a waste of time to define what the nozzle is, though we could calculate the water volume to produce 3 KW with a well defined head which you do not have due to the bad pipes installed.
                      >
                      > Assuming you have a net 45 meter head and 3 KW the water volume would be 3000= 45 *6 * Vol ; Vol= 11.1 liter/sec
                      >
                      > Vjet = Sq-rt( 2 * 9,81 * 45) = 29,71,4 m/s = 2971,4 cms/sc
                      >
                      > Jet Area = 11100/ 2971,4 = 3,7356 cms^2
                      >
                      > Jet dia = 2* Sq-rt ( 3,7356/3.14) = 2,18 cms diameter
                      >
                      > Nando
                      >
                      >
                      >
                      > ----- Original Message -----
                      > From: Thor
                      > To: microhydro@yahoogroups.com
                      > Sent: Thursday, August 02, 2012 08:12
                      > Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??
                      >
                      >
                      >
                      >
                      >
                      > Nando.
                      >
                      > Many thanks for your detailed reply.
                      >
                      > The ELC is all wrong as you said, I traced the PCB, drew a schematic with ExpressPCB and uploaded a GIF image of the result in the photos, must remember to put a strong warning there so nobody thinks it is good and tries to make one!!
                      >
                      > I can not see it detects zero crossing at all, only the rectified DC-supply voltage to the ELC itself.
                      >
                      > The big load switching semiconductor is a TRIAC, infinite resistance between MT1 and MT2 both ways and approx. 100ohms gate to MT1. The MOC3020 is an instant switching Opto-TRIAC.
                      >
                      > I have one or two old ELCs I once made lying around, they were originally designed for a bit more power, 10-30kW, have 15 fixed zero switching ON/OFF loads and one variable phase controlled load which was 2x bigger than the fixed loads.
                      >
                      > The fixed loads turn on one by one (count up) if the variable load is at more than 75% and they turn off (count down) if the variable load is less than 25%.
                      >
                      > In this case it should be enough to have 4x500W fixed loads and one 1000W variable. (Of course it would be fun to mount 15x200W old light bulbs in a row as loads and and have two parallel bulbs as the variable. Unfortunately that would not last long enough !!)
                      >
                      > The pipe is another problem, the turbine maker put a 2" pipe thread on the input so that explains the very narrow short section at the turbine.
                      >
                      > The jet diameter is unknown to me, from the picture I took it looks like it may be about 30mm. Is that all right ?
                      >
                      > Then there is the wheel, it somehow does not look quite right, the Hartvigsen Hydro spoons look so much better :-)
                      >
                      > I also noticed in the picture of the wheel that the bearings seem to be ordinary sealed ball bearings mounted right inside the water chamber with no additional seals and no means of lubrication. That surely will be a problem very soon.
                      >
                      > I am afraid there are quite a few things to do before this one works properly .
                      >
                      > Best regards.
                      >
                      > Thor.
                      >
                      > --- In microhydro@yahoogroups.com, "Nando" <nando37@> wrote:
                      > >
                      > > Thor :
                      > >
                      > > The ELC is a common PWM voltage regulator in reverse mode, this means that it is reading the rectified output voltage and if is higher than the reference starts to PWM modulate the power resistor to bring the voltage down via 50 HZ phase loading.
                      > >
                      > > This regulator is poor, the TL494 is the equivalent to the SG3825 family and has a wrong use.
                      > >
                      > > The TL494 has two amplifiers, one defined for current detection that can be used to detect the Zero crossing but due to the oscillator circuit the detector requires a clamp to limit the behavior of the oscillator lower transitional and keep the saw tooth working properly, and the second amplifier to detect the voltage fluctuations to turn ON the output pulse for the TRIAC ON position in the 180 degrees angle of the sine wave.
                      > >
                      > > This design is better for a Vdc control and I may wonder if the TRIAC is not a TRIAC but a MosFet -- does the device have a heat sink dissipator ?. Can you read the voltage that triggers the device to see if it is 12 volts with a width time equal to less than 180 degrees or around 2 or 3 volts ( if it is a TRIAC).
                      > >
                      > > The ELC in this case would have been better using two 555 IC, one as a Cero crossing point trigger with the time constant varied by the rectified voltage to trigger the second 555 to give a 30 or so microseconds pulse to turn the Triac ON phase wise, from the 180 degrees backwards incremented. -- This I did shortly after the 555 appeared in the market converting an equivalent circuit using a lot of discrete parts .
                      > >
                      > > Basically the ELC needs a cero crossing detector to trigger or reset an saw tooth oscillator with the amplitude of the saw tooth varied by the variable AC voltage ( rectified and slightly filtered) to cross the upper trigger point prior the reaching of the 50 Hz ( 20 ms) 180 degrees crossing to trigger the second 555 to generate the 30 or so microseconds to trigger the triac.
                      > >
                      > > We also need an amplifier to be able to modulate the saw tooth against a voltage reference.
                      > >
                      > > There is a need of a good motor Running Capacitor , connected in parallel to the generator ) to reduce the sine wave distortion that the TRIAC ON pulses generate.
                      > >
                      > > The head needed is defined by the PCD diameter of the turbine and the frequency to give the peripheral velocity of the turbine.
                      > >
                      > > The dynamic pressure drops too much !!
                      > >
                      > > The 40 meters 84 mm diameter is presenting too much water friction !! The 1 meter long 70 mm diameter is reducing the water volume too much !!
                      > >
                      > > To determine the HEAD
                      > >
                      > > So for a 1500 RPM turbine the RPS is 1500/60 sec = 25 RPS
                      > >
                      > > H= Head
                      > >
                      > > 25 RPS * pi * Diameter turbine
                      > >
                      > > 25 * 3.14 * 0.19 = 14,92 m/s
                      > >
                      > > Vjet = 100/49* 14,92= 30,45 m/s
                      > >
                      > > 30,45 ^2 = 2 * 9,81 * H where H = 47,27m/s Which is close to the reported : about 50 meters static ,
                      > >
                      > > For a 3 KW the ELC should control two - 1 KW full ON/OFF loads plus the primary phase controlled 1 KW load as a minimum for best operation, though I would make the ELC differently and in this case a primary phase loaded 500 watts, a second full ON/OFF 500 watts , then 2 - 1 KW each load to have a full complement loading , this if the maximum power is 3 KW, though I would suggest the last 1 KW load to be a 1,5 KW load in case that the generator can produce more than 3 KW.
                      > >
                      > > Nando
                      > >
                      > > ----- Original Message -----
                      > > From: Thor
                      > > To: microhydro@yahoogroups.com
                      > > Sent: Tuesday, July 31, 2012 16:51
                      > > Subject: [microhydro] Does Someone know this Turbine-Generator-ELC ??
                      > >
                      > >
                      > >
                      > > Hi everybody.
                      > >
                      > > First I was only going to ask if anybody had seen the ELC in the pictures I posted, but then decided to tell the full story as I far as I know it.
                      > >
                      > > I have been asked for help to get this Micro Hydro setup running properly. It was ordered and installed last year but so far almost nothing has worked as expected.
                      > >
                      > > Today I visited the site and took some pictures and measurements, (see group photos, album China-Turbine-In-Iceland http://groups.yahoo.com/group/microhydro/photos/album/1255983797/pic/list.
                      > >
                      > > The total head is approx. 50m, the static pressure with no flow is 4.8bar which drops to 3.0 bar at maximum needle valve opening.
                      > >
                      > > There is plenty of water, the pipe is always full.
                      > >
                      > > I was told the upper part of the penstock is 200m long HDPE pipe 110/6mm (internal dia. 108mm)
                      > > The lower part is 40m long HDPE 90/8mm (internal dia. 84mm)
                      > > there is also a short (1m long, less than 70mm dia.?) steel pipe where the penstock connects to the turbine.
                      > >
                      > > They ordered and got a turbine/generator rated for 50Hz/230V/3kW, 1500rpm at 40m head. It was known that the pipe would limit the flow and they did expect to run at approx. 80% pressure.
                      > >
                      > > First problem: The turbine did not come with a needle valve, just a far too wide fixed nozzle, so the owners made one, rather difficult to turn, but does not leak and seems to work all right.
                      > >
                      > > Second problem: slip ring damage.
                      > > The generator is single phase with 2 slip rings and 2 brushes on each ring. The brush holders are made from thin sheet metal, the brushes are very loose and originally they were positioned some 15-20mm away from the rings so the brushes got stuck in the holders with arcing and ring damage. The rings have been repaired and the position of brush holders has been fixed somewhat, but it is still not good.
                      > >
                      > > Third problem: The ELC has never worked properly. It has a single 3kW dump load controlled by a TRIAC. It senses the voltage and fortunately the generator seems properly made to give 220-230V at 50Hz.
                      > > But the ELC does not work smoothly, it either diverts no power to the dump load or far too much so the voltage and speed are just fluctuating wildly 170-240V 40-55Hz. The ELC has IC TL494CN which controls the TRIAC via MOC3020 Optocoupler. The TRIAC is unknown. The manufacturer used grinder on all the markings but failed to delete the IC´s :-)
                      > >
                      > > Fourth problem: The power output is much lower than expected, it seems to be at maximum running at 3.6bar pressure but then it is only approx. 5.6A x 230V = 1.3kW
                      > > We measured the last one at 50Hz, it is a bit more if we lower speed and voltage, 40Hz 170V 12.1A = 2.1kW
                      > >
                      > > By measuring the distance from nozzle to shaft it looks like effective diameter of wheel is approx. 190mm. I think that is a bit too big for 1500rpm at 40m head.
                      > >
                      > > Any information regarding this appreciated.
                      > >
                      > > Best regards.
                      > >
                      > > Thor.
                      > > (Electronics technician and a long time lurker in this group)
                      > >
                      > >
                      > >
                      > >
                      > >
                      > > [Non-text portions of this message have been removed]
                      > >
                      >
                      >
                      >
                      >
                      >
                      > [Non-text portions of this message have been removed]
                      >





                      [Non-text portions of this message have been removed]
                    • Thor
                      Michael. You are right that if done properly it is possible to use PWM to control the load on a generator. The problem is that it is not done properly with
                      Message 10 of 15 , Aug 3, 2012
                      • 0 Attachment
                        Michael.

                        You are right that if done properly it is possible to use PWM to control the load on a generator.

                        The problem is that it is not done properly with this ELC.
                        There are so many things wrong in its design that it is a waste of time to even try to make it work properly.

                        Best regards.

                        Thor.


                        --- In microhydro@yahoogroups.com, "Michael" <mmk_tsm@...> wrote:
                        >
                        > Hello,
                        > in relation to the controller, which you guys say doesnt work:
                        > My question is,
                        > is the concept viable? In the schematic Thor has drawn, the generator voltage is the feedback input to the PWM ic, so they are attempting to regulate the generator voltage. Done properly would it work, i.e to use a PWM chip to control the load on a generator to keep the generator voltage constant? For example if the voltage was rectified to DC, and smoothed, could the PWM output switch on a load, and control load.
                        >
                        > Michael.
                        >
                        >
                        >
                        >
                        > --- In microhydro@yahoogroups.com, "Nando" <nando37@> wrote:
                        > >
                        > > THOR:
                        > >
                        > > You got the rest of the analysis and the idea of your ELC is not practical
                        > >
                        > > The ELC with 15 loads, you just need for easy control of 3 KW , to have 6 loads of 500 watts and the one used as Phase control to be also 500 watts -- it is an error to use a double load there .
                        > >
                        > > Also use a 10 microfarad motor RUNNING CAPACITOR in parallel with the power lines to reduce the Triac variable phase On pulses distortion it generates,
                        > >
                        > > Do not use lamps as active ballast loads it is expensive if the lamps blow.
                        > >
                        > > I have not tried to calculate the nozzle diameter because the information has too many errors and it is a waste of time to define what the nozzle is, though we could calculate the water volume to produce 3 KW with a well defined head which you do not have due to the bad pipes installed.
                        > >
                        > > Assuming you have a net 45 meter head and 3 KW the water volume would be 3000= 45 *6 * Vol ; Vol= 11.1 liter/sec
                        > >
                        > > Vjet = Sq-rt( 2 * 9,81 * 45) = 29,71,4 m/s = 2971,4 cms/sc
                        > >
                        > > Jet Area = 11100/ 2971,4 = 3,7356 cms^2
                        > >
                        > > Jet dia = 2* Sq-rt ( 3,7356/3.14) = 2,18 cms diameter
                        > >
                        > > Nando
                        > >
                        > >
                        > >
                        > > ----- Original Message -----
                        > > From: Thor
                        > > To: microhydro@yahoogroups.com
                        > > Sent: Thursday, August 02, 2012 08:12
                        > > Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??
                        > >
                        > >
                        > >
                        > >
                        > >
                        > > Nando.
                        > >
                        > > Many thanks for your detailed reply.
                        > >
                        > > The ELC is all wrong as you said, I traced the PCB, drew a schematic with ExpressPCB and uploaded a GIF image of the result in the photos, must remember to put a strong warning there so nobody thinks it is good and tries to make one!!
                        > >
                        > > I can not see it detects zero crossing at all, only the rectified DC-supply voltage to the ELC itself.
                        > >
                        > > The big load switching semiconductor is a TRIAC, infinite resistance between MT1 and MT2 both ways and approx. 100ohms gate to MT1. The MOC3020 is an instant switching Opto-TRIAC.
                        > >
                        > > I have one or two old ELCs I once made lying around, they were originally designed for a bit more power, 10-30kW, have 15 fixed zero switching ON/OFF loads and one variable phase controlled load which was 2x bigger than the fixed loads.
                        > >
                        > > The fixed loads turn on one by one (count up) if the variable load is at more than 75% and they turn off (count down) if the variable load is less than 25%.
                        > >
                        > > In this case it should be enough to have 4x500W fixed loads and one 1000W variable. (Of course it would be fun to mount 15x200W old light bulbs in a row as loads and and have two parallel bulbs as the variable. Unfortunately that would not last long enough !!)
                        > >
                        > > The pipe is another problem, the turbine maker put a 2" pipe thread on the input so that explains the very narrow short section at the turbine.
                        > >
                        > > The jet diameter is unknown to me, from the picture I took it looks like it may be about 30mm. Is that all right ?
                        > >
                        > > Then there is the wheel, it somehow does not look quite right, the Hartvigsen Hydro spoons look so much better :-)
                        > >
                        > > I also noticed in the picture of the wheel that the bearings seem to be ordinary sealed ball bearings mounted right inside the water chamber with no additional seals and no means of lubrication. That surely will be a problem very soon.
                        > >
                        > > I am afraid there are quite a few things to do before this one works properly .
                        > >
                        > > Best regards.
                        > >
                        > > Thor.
                        > >
                        > > --- In microhydro@yahoogroups.com, "Nando" <nando37@> wrote:
                        > > >
                        > > > Thor :
                        > > >
                        > > > The ELC is a common PWM voltage regulator in reverse mode, this means that it is reading the rectified output voltage and if is higher than the reference starts to PWM modulate the power resistor to bring the voltage down via 50 HZ phase loading.
                        > > >
                        > > > This regulator is poor, the TL494 is the equivalent to the SG3825 family and has a wrong use.
                        > > >
                        > > > The TL494 has two amplifiers, one defined for current detection that can be used to detect the Zero crossing but due to the oscillator circuit the detector requires a clamp to limit the behavior of the oscillator lower transitional and keep the saw tooth working properly, and the second amplifier to detect the voltage fluctuations to turn ON the output pulse for the TRIAC ON position in the 180 degrees angle of the sine wave.
                        > > >
                        > > > This design is better for a Vdc control and I may wonder if the TRIAC is not a TRIAC but a MosFet -- does the device have a heat sink dissipator ?. Can you read the voltage that triggers the device to see if it is 12 volts with a width time equal to less than 180 degrees or around 2 or 3 volts ( if it is a TRIAC).
                        > > >
                        > > > The ELC in this case would have been better using two 555 IC, one as a Cero crossing point trigger with the time constant varied by the rectified voltage to trigger the second 555 to give a 30 or so microseconds pulse to turn the Triac ON phase wise, from the 180 degrees backwards incremented. -- This I did shortly after the 555 appeared in the market converting an equivalent circuit using a lot of discrete parts .
                        > > >
                        > > > Basically the ELC needs a cero crossing detector to trigger or reset an saw tooth oscillator with the amplitude of the saw tooth varied by the variable AC voltage ( rectified and slightly filtered) to cross the upper trigger point prior the reaching of the 50 Hz ( 20 ms) 180 degrees crossing to trigger the second 555 to generate the 30 or so microseconds to trigger the triac.
                        > > >
                        > > > We also need an amplifier to be able to modulate the saw tooth against a voltage reference.
                        > > >
                        > > > There is a need of a good motor Running Capacitor , connected in parallel to the generator ) to reduce the sine wave distortion that the TRIAC ON pulses generate.
                        > > >
                        > > > The head needed is defined by the PCD diameter of the turbine and the frequency to give the peripheral velocity of the turbine.
                        > > >
                        > > > The dynamic pressure drops too much !!
                        > > >
                        > > > The 40 meters 84 mm diameter is presenting too much water friction !! The 1 meter long 70 mm diameter is reducing the water volume too much !!
                        > > >
                        > > > To determine the HEAD
                        > > >
                        > > > So for a 1500 RPM turbine the RPS is 1500/60 sec = 25 RPS
                        > > >
                        > > > H= Head
                        > > >
                        > > > 25 RPS * pi * Diameter turbine
                        > > >
                        > > > 25 * 3.14 * 0.19 = 14,92 m/s
                        > > >
                        > > > Vjet = 100/49* 14,92= 30,45 m/s
                        > > >
                        > > > 30,45 ^2 = 2 * 9,81 * H where H = 47,27m/s Which is close to the reported : about 50 meters static ,
                        > > >
                        > > > For a 3 KW the ELC should control two - 1 KW full ON/OFF loads plus the primary phase controlled 1 KW load as a minimum for best operation, though I would make the ELC differently and in this case a primary phase loaded 500 watts, a second full ON/OFF 500 watts , then 2 - 1 KW each load to have a full complement loading , this if the maximum power is 3 KW, though I would suggest the last 1 KW load to be a 1,5 KW load in case that the generator can produce more than 3 KW.
                        > > >
                        > > > Nando
                        > > >
                        > > > ----- Original Message -----
                        > > > From: Thor
                        > > > To: microhydro@yahoogroups.com
                        > > > Sent: Tuesday, July 31, 2012 16:51
                        > > > Subject: [microhydro] Does Someone know this Turbine-Generator-ELC ??
                        > > >
                        > > >
                        > > >
                        > > > Hi everybody.
                        > > >
                        > > > First I was only going to ask if anybody had seen the ELC in the pictures I posted, but then decided to tell the full story as I far as I know it.
                        > > >
                        > > > I have been asked for help to get this Micro Hydro setup running properly. It was ordered and installed last year but so far almost nothing has worked as expected.
                        > > >
                        > > > Today I visited the site and took some pictures and measurements, (see group photos, album China-Turbine-In-Iceland http://groups.yahoo.com/group/microhydro/photos/album/1255983797/pic/list.
                        > > >
                        > > > The total head is approx. 50m, the static pressure with no flow is 4.8bar which drops to 3.0 bar at maximum needle valve opening.
                        > > >
                        > > > There is plenty of water, the pipe is always full.
                        > > >
                        > > > I was told the upper part of the penstock is 200m long HDPE pipe 110/6mm (internal dia. 108mm)
                        > > > The lower part is 40m long HDPE 90/8mm (internal dia. 84mm)
                        > > > there is also a short (1m long, less than 70mm dia.?) steel pipe where the penstock connects to the turbine.
                        > > >
                        > > > They ordered and got a turbine/generator rated for 50Hz/230V/3kW, 1500rpm at 40m head. It was known that the pipe would limit the flow and they did expect to run at approx. 80% pressure.
                        > > >
                        > > > First problem: The turbine did not come with a needle valve, just a far too wide fixed nozzle, so the owners made one, rather difficult to turn, but does not leak and seems to work all right.
                        > > >
                        > > > Second problem: slip ring damage.
                        > > > The generator is single phase with 2 slip rings and 2 brushes on each ring. The brush holders are made from thin sheet metal, the brushes are very loose and originally they were positioned some 15-20mm away from the rings so the brushes got stuck in the holders with arcing and ring damage. The rings have been repaired and the position of brush holders has been fixed somewhat, but it is still not good.
                        > > >
                        > > > Third problem: The ELC has never worked properly. It has a single 3kW dump load controlled by a TRIAC. It senses the voltage and fortunately the generator seems properly made to give 220-230V at 50Hz.
                        > > > But the ELC does not work smoothly, it either diverts no power to the dump load or far too much so the voltage and speed are just fluctuating wildly 170-240V 40-55Hz. The ELC has IC TL494CN which controls the TRIAC via MOC3020 Optocoupler. The TRIAC is unknown. The manufacturer used grinder on all the markings but failed to delete the IC´s :-)
                        > > >
                        > > > Fourth problem: The power output is much lower than expected, it seems to be at maximum running at 3.6bar pressure but then it is only approx. 5.6A x 230V = 1.3kW
                        > > > We measured the last one at 50Hz, it is a bit more if we lower speed and voltage, 40Hz 170V 12.1A = 2.1kW
                        > > >
                        > > > By measuring the distance from nozzle to shaft it looks like effective diameter of wheel is approx. 190mm. I think that is a bit too big for 1500rpm at 40m head.
                        > > >
                        > > > Any information regarding this appreciated.
                        > > >
                        > > > Best regards.
                        > > >
                        > > > Thor.
                        > > > (Electronics technician and a long time lurker in this group)
                        > > >
                        > > >
                        > > >
                        > > >
                        > > >
                        > > > [Non-text portions of this message have been removed]
                        > > >
                        > >
                        > >
                        > >
                        > >
                        > >
                        > > [Non-text portions of this message have been removed]
                        > >
                        >
                      • Nando
                        I need to add that the Mosfet has to be the AC type which means two mosfets connected source to source and gates together and the Drains are in parallel with
                        Message 11 of 15 , Aug 3, 2012
                        • 0 Attachment
                          I need to add that the Mosfet has to be the AC type which means two mosfets connected source to source and gates together and the Drains are in parallel with the generator of course one of the drains having a ballast load and the ckt oscillator around 10-15 KHZ with proper Vac isolation .

                          Nando


                          ----- Original Message -----
                          From: Nando
                          To: microhydro@yahoogroups.com
                          Sent: Friday, August 03, 2012 11:04
                          Subject: Re: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??



                          Michael:

                          The circuit fails because it is using a Triac and the circuit if you examine it carefully will see that just a comparator is used and for that purpose a power Mosfet is needed and not a TRIAC plus a ballast load to load the generator to reduce the DC voltage depending on the time constant of the storage capacitor prior to the Voltage regulator ( 12 volts ) .

                          The circuit make work if the Triac is replaced with a high Voltage Mosfet with a ballast equal to close the peak power and the filter in the rectified circuit is set to have certain low voltage.

                          I have used this type of circuit to regulate induction motor as generators using the sine wave rectified with an independent time constant for the PWM to operate properly.

                          Nando

                          ----- Original Message -----
                          From: Michael
                          To: microhydro@yahoogroups.com
                          Sent: Friday, August 03, 2012 09:32
                          Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??

                          Hello,
                          in relation to the controller, which you guys say doesnt work:
                          My question is,
                          is the concept viable? In the schematic Thor has drawn, the generator voltage is the feedback input to the PWM ic, so they are attempting to regulate the generator voltage. Done properly would it work, i.e to use a PWM chip to control the load on a generator to keep the generator voltage constant? For example if the voltage was rectified to DC, and smoothed, could the PWM output switch on a load, and control load.

                          Michael.

                          --- In microhydro@yahoogroups.com, "Nando" <nando37@...> wrote:
                          >
                          > THOR:
                          >
                          > You got the rest of the analysis and the idea of your ELC is not practical
                          >
                          > The ELC with 15 loads, you just need for easy control of 3 KW , to have 6 loads of 500 watts and the one used as Phase control to be also 500 watts -- it is an error to use a double load there .
                          >
                          > Also use a 10 microfarad motor RUNNING CAPACITOR in parallel with the power lines to reduce the Triac variable phase On pulses distortion it generates,
                          >
                          > Do not use lamps as active ballast loads it is expensive if the lamps blow.
                          >
                          > I have not tried to calculate the nozzle diameter because the information has too many errors and it is a waste of time to define what the nozzle is, though we could calculate the water volume to produce 3 KW with a well defined head which you do not have due to the bad pipes installed.
                          >
                          > Assuming you have a net 45 meter head and 3 KW the water volume would be 3000= 45 *6 * Vol ; Vol= 11.1 liter/sec
                          >
                          > Vjet = Sq-rt( 2 * 9,81 * 45) = 29,71,4 m/s = 2971,4 cms/sc
                          >
                          > Jet Area = 11100/ 2971,4 = 3,7356 cms^2
                          >
                          > Jet dia = 2* Sq-rt ( 3,7356/3.14) = 2,18 cms diameter
                          >
                          > Nando
                          >
                          >
                          >
                          > ----- Original Message -----
                          > From: Thor
                          > To: microhydro@yahoogroups.com
                          > Sent: Thursday, August 02, 2012 08:12
                          > Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??
                          >
                          >
                          >
                          >
                          >
                          > Nando.
                          >
                          > Many thanks for your detailed reply.
                          >
                          > The ELC is all wrong as you said, I traced the PCB, drew a schematic with ExpressPCB and uploaded a GIF image of the result in the photos, must remember to put a strong warning there so nobody thinks it is good and tries to make one!!
                          >
                          > I can not see it detects zero crossing at all, only the rectified DC-supply voltage to the ELC itself.
                          >
                          > The big load switching semiconductor is a TRIAC, infinite resistance between MT1 and MT2 both ways and approx. 100ohms gate to MT1. The MOC3020 is an instant switching Opto-TRIAC.
                          >
                          > I have one or two old ELCs I once made lying around, they were originally designed for a bit more power, 10-30kW, have 15 fixed zero switching ON/OFF loads and one variable phase controlled load which was 2x bigger than the fixed loads.
                          >
                          > The fixed loads turn on one by one (count up) if the variable load is at more than 75% and they turn off (count down) if the variable load is less than 25%.
                          >
                          > In this case it should be enough to have 4x500W fixed loads and one 1000W variable. (Of course it would be fun to mount 15x200W old light bulbs in a row as loads and and have two parallel bulbs as the variable. Unfortunately that would not last long enough !!)
                          >
                          > The pipe is another problem, the turbine maker put a 2" pipe thread on the input so that explains the very narrow short section at the turbine.
                          >
                          > The jet diameter is unknown to me, from the picture I took it looks like it may be about 30mm. Is that all right ?
                          >
                          > Then there is the wheel, it somehow does not look quite right, the Hartvigsen Hydro spoons look so much better :-)
                          >
                          > I also noticed in the picture of the wheel that the bearings seem to be ordinary sealed ball bearings mounted right inside the water chamber with no additional seals and no means of lubrication. That surely will be a problem very soon.
                          >
                          > I am afraid there are quite a few things to do before this one works properly .
                          >
                          > Best regards.
                          >
                          > Thor.
                          >
                          > --- In microhydro@yahoogroups.com, "Nando" <nando37@> wrote:
                          > >
                          > > Thor :
                          > >
                          > > The ELC is a common PWM voltage regulator in reverse mode, this means that it is reading the rectified output voltage and if is higher than the reference starts to PWM modulate the power resistor to bring the voltage down via 50 HZ phase loading.
                          > >
                          > > This regulator is poor, the TL494 is the equivalent to the SG3825 family and has a wrong use.
                          > >
                          > > The TL494 has two amplifiers, one defined for current detection that can be used to detect the Zero crossing but due to the oscillator circuit the detector requires a clamp to limit the behavior of the oscillator lower transitional and keep the saw tooth working properly, and the second amplifier to detect the voltage fluctuations to turn ON the output pulse for the TRIAC ON position in the 180 degrees angle of the sine wave.
                          > >
                          > > This design is better for a Vdc control and I may wonder if the TRIAC is not a TRIAC but a MosFet -- does the device have a heat sink dissipator ?. Can you read the voltage that triggers the device to see if it is 12 volts with a width time equal to less than 180 degrees or around 2 or 3 volts ( if it is a TRIAC).
                          > >
                          > > The ELC in this case would have been better using two 555 IC, one as a Cero crossing point trigger with the time constant varied by the rectified voltage to trigger the second 555 to give a 30 or so microseconds pulse to turn the Triac ON phase wise, from the 180 degrees backwards incremented. -- This I did shortly after the 555 appeared in the market converting an equivalent circuit using a lot of discrete parts .
                          > >
                          > > Basically the ELC needs a cero crossing detector to trigger or reset an saw tooth oscillator with the amplitude of the saw tooth varied by the variable AC voltage ( rectified and slightly filtered) to cross the upper trigger point prior the reaching of the 50 Hz ( 20 ms) 180 degrees crossing to trigger the second 555 to generate the 30 or so microseconds to trigger the triac.
                          > >
                          > > We also need an amplifier to be able to modulate the saw tooth against a voltage reference.
                          > >
                          > > There is a need of a good motor Running Capacitor , connected in parallel to the generator ) to reduce the sine wave distortion that the TRIAC ON pulses generate.
                          > >
                          > > The head needed is defined by the PCD diameter of the turbine and the frequency to give the peripheral velocity of the turbine.
                          > >
                          > > The dynamic pressure drops too much !!
                          > >
                          > > The 40 meters 84 mm diameter is presenting too much water friction !! The 1 meter long 70 mm diameter is reducing the water volume too much !!
                          > >
                          > > To determine the HEAD
                          > >
                          > > So for a 1500 RPM turbine the RPS is 1500/60 sec = 25 RPS
                          > >
                          > > H= Head
                          > >
                          > > 25 RPS * pi * Diameter turbine
                          > >
                          > > 25 * 3.14 * 0.19 = 14,92 m/s
                          > >
                          > > Vjet = 100/49* 14,92= 30,45 m/s
                          > >
                          > > 30,45 ^2 = 2 * 9,81 * H where H = 47,27m/s Which is close to the reported : about 50 meters static ,
                          > >
                          > > For a 3 KW the ELC should control two - 1 KW full ON/OFF loads plus the primary phase controlled 1 KW load as a minimum for best operation, though I would make the ELC differently and in this case a primary phase loaded 500 watts, a second full ON/OFF 500 watts , then 2 - 1 KW each load to have a full complement loading , this if the maximum power is 3 KW, though I would suggest the last 1 KW load to be a 1,5 KW load in case that the generator can produce more than 3 KW.
                          > >
                          > > Nando
                          > >
                          > > ----- Original Message -----
                          > > From: Thor
                          > > To: microhydro@yahoogroups.com
                          > > Sent: Tuesday, July 31, 2012 16:51
                          > > Subject: [microhydro] Does Someone know this Turbine-Generator-ELC ??
                          > >
                          > >
                          > >
                          > > Hi everybody.
                          > >
                          > > First I was only going to ask if anybody had seen the ELC in the pictures I posted, but then decided to tell the full story as I far as I know it.
                          > >
                          > > I have been asked for help to get this Micro Hydro setup running properly. It was ordered and installed last year but so far almost nothing has worked as expected.
                          > >
                          > > Today I visited the site and took some pictures and measurements, (see group photos, album China-Turbine-In-Iceland http://groups.yahoo.com/group/microhydro/photos/album/1255983797/pic/list.
                          > >
                          > > The total head is approx. 50m, the static pressure with no flow is 4.8bar which drops to 3.0 bar at maximum needle valve opening.
                          > >
                          > > There is plenty of water, the pipe is always full.
                          > >
                          > > I was told the upper part of the penstock is 200m long HDPE pipe 110/6mm (internal dia. 108mm)
                          > > The lower part is 40m long HDPE 90/8mm (internal dia. 84mm)
                          > > there is also a short (1m long, less than 70mm dia.?) steel pipe where the penstock connects to the turbine.
                          > >
                          > > They ordered and got a turbine/generator rated for 50Hz/230V/3kW, 1500rpm at 40m head. It was known that the pipe would limit the flow and they did expect to run at approx. 80% pressure.
                          > >
                          > > First problem: The turbine did not come with a needle valve, just a far too wide fixed nozzle, so the owners made one, rather difficult to turn, but does not leak and seems to work all right.
                          > >
                          > > Second problem: slip ring damage.
                          > > The generator is single phase with 2 slip rings and 2 brushes on each ring. The brush holders are made from thin sheet metal, the brushes are very loose and originally they were positioned some 15-20mm away from the rings so the brushes got stuck in the holders with arcing and ring damage. The rings have been repaired and the position of brush holders has been fixed somewhat, but it is still not good.
                          > >
                          > > Third problem: The ELC has never worked properly. It has a single 3kW dump load controlled by a TRIAC. It senses the voltage and fortunately the generator seems properly made to give 220-230V at 50Hz.
                          > > But the ELC does not work smoothly, it either diverts no power to the dump load or far too much so the voltage and speed are just fluctuating wildly 170-240V 40-55Hz. The ELC has IC TL494CN which controls the TRIAC via MOC3020 Optocoupler. The TRIAC is unknown. The manufacturer used grinder on all the markings but failed to delete the IC´s :-)
                          > >
                          > > Fourth problem: The power output is much lower than expected, it seems to be at maximum running at 3.6bar pressure but then it is only approx. 5.6A x 230V = 1.3kW
                          > > We measured the last one at 50Hz, it is a bit more if we lower speed and voltage, 40Hz 170V 12.1A = 2.1kW
                          > >
                          > > By measuring the distance from nozzle to shaft it looks like effective diameter of wheel is approx. 190mm. I think that is a bit too big for 1500rpm at 40m head.
                          > >
                          > > Any information regarding this appreciated.
                          > >
                          > > Best regards.
                          > >
                          > > Thor.
                          > > (Electronics technician and a long time lurker in this group)
                          > >
                          > >
                          > >
                          > >
                          > >
                          > > [Non-text portions of this message have been removed]
                          > >
                          >
                          >
                          >
                          >
                          >
                          > [Non-text portions of this message have been removed]
                          >

                          [Non-text portions of this message have been removed]





                          [Non-text portions of this message have been removed]
                        • Thor
                          Nando. Now you got me confused for a moment (AC type Mosfet? and ...drains are in parallel with the generator...??) - no problem now I know what you are
                          Message 12 of 15 , Aug 4, 2012
                          • 0 Attachment
                            Nando.

                            Now you got me confused for a moment (AC type Mosfet? and ...drains are in parallel with the generator...??) - no problem now I know what you are saying.

                            I have never actually used MOSFETs for AC-switching - only Thyristor or TRIAC SSRs - but Google helped me back on track.

                            This diagram I found shows the principle.
                            http://easy-electronics4u.blogspot.com/2012/02/switch-ac-loads-using-mosfets-as-relay.html

                            The "dump load" in the diagram is the 10k resistor and LEDs.

                            Both MOSFETs are N-Channel and they conduct (D-S) in both directions when turned ON by applying positive G-S voltage. However we must connect two in series because of the parasitic D-S diode in the MOSFETs.

                            In the real world we also have to take care of a couple of more things.

                            - The MOSFETs must be mounted with insulation on a suitably large heatsink.

                            - MOSFETs must be turned ON/OFF very fast so they do not heat up and burn (the 7400 in the diagram I mentioned will not be sufficiently fast if the D-S current is high) and they must also be fully OFF (or fully ON) during power-up and power-down - dedicated Driver ICs exist and could be used.

                            - The Gate Driver Circuit must have isolated power supply (transformer) and it should also be isolated from the actual control circuit (Opto-coupler).

                            The driver supply can be a low power 10-15V DC with a low ESR capacitor just to make sure we have enough gate current to charge the gate capacitance and turn the MOSFETs ON/OFF fast enough - this gate current is surprisingly high but only for microseconds.

                            Then one question:
                            Has some manufacturer made a High Voltage (>230V) High Current (>10A) Fast Switching (>20kHz) MOSFET Solid State Relay for AC with all these functions inside?
                            It would be a very useful building block for ELC but I can only find small ones like http://www.anglia.com/newsarchive/2233.asp?article_id=3005.
                            (They call it "High Current" but that is 0.2A!!)

                            Best regards.

                            Thor.


                            --- In microhydro@yahoogroups.com, "Nando" <nando37@...> wrote:
                            >
                            > I need to add that the Mosfet has to be the AC type which means two mosfets connected source to source and gates together and the Drains are in parallel with the generator of course one of the drains having a ballast load and the ckt oscillator around 10-15 KHZ with proper Vac isolation .
                            >
                            > Nando
                            >
                            >
                            > ----- Original Message -----
                            > From: Nando
                            > To: microhydro@yahoogroups.com
                            > Sent: Friday, August 03, 2012 11:04
                            > Subject: Re: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??
                            >
                            >
                            >
                            > Michael:
                            >
                            > The circuit fails because it is using a Triac and the circuit if you examine it carefully will see that just a comparator is used and for that purpose a power Mosfet is needed and not a TRIAC plus a ballast load to load the generator to reduce the DC voltage depending on the time constant of the storage capacitor prior to the Voltage regulator ( 12 volts ) .
                            >
                            > The circuit make work if the Triac is replaced with a high Voltage Mosfet with a ballast equal to close the peak power and the filter in the rectified circuit is set to have certain low voltage.
                            >
                            > I have used this type of circuit to regulate induction motor as generators using the sine wave rectified with an independent time constant for the PWM to operate properly.
                            >
                            > Nando
                            >
                            > ----- Original Message -----
                            > From: Michael
                            > To: microhydro@yahoogroups.com
                            > Sent: Friday, August 03, 2012 09:32
                            > Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??
                            >
                            > Hello,
                            > in relation to the controller, which you guys say doesnt work:
                            > My question is,
                            > is the concept viable? In the schematic Thor has drawn, the generator voltage is the feedback input to the PWM ic, so they are attempting to regulate the generator voltage. Done properly would it work, i.e to use a PWM chip to control the load on a generator to keep the generator voltage constant? For example if the voltage was rectified to DC, and smoothed, could the PWM output switch on a load, and control load.
                            >
                            > Michael.
                            >
                            > --- In microhydro@yahoogroups.com, "Nando" <nando37@> wrote:
                            > >
                            > > THOR:
                            > >
                            > > You got the rest of the analysis and the idea of your ELC is not practical
                            > >
                            > > The ELC with 15 loads, you just need for easy control of 3 KW , to have 6 loads of 500 watts and the one used as Phase control to be also 500 watts -- it is an error to use a double load there .
                            > >
                            > > Also use a 10 microfarad motor RUNNING CAPACITOR in parallel with the power lines to reduce the Triac variable phase On pulses distortion it generates,
                            > >
                            > > Do not use lamps as active ballast loads it is expensive if the lamps blow.
                            > >
                            > > I have not tried to calculate the nozzle diameter because the information has too many errors and it is a waste of time to define what the nozzle is, though we could calculate the water volume to produce 3 KW with a well defined head which you do not have due to the bad pipes installed.
                            > >
                            > > Assuming you have a net 45 meter head and 3 KW the water volume would be 3000= 45 *6 * Vol ; Vol= 11.1 liter/sec
                            > >
                            > > Vjet = Sq-rt( 2 * 9,81 * 45) = 29,71,4 m/s = 2971,4 cms/sc
                            > >
                            > > Jet Area = 11100/ 2971,4 = 3,7356 cms^2
                            > >
                            > > Jet dia = 2* Sq-rt ( 3,7356/3.14) = 2,18 cms diameter
                            > >
                            > > Nando
                            > >
                            > >
                            > >
                            > > ----- Original Message -----
                            > > From: Thor
                            > > To: microhydro@yahoogroups.com
                            > > Sent: Thursday, August 02, 2012 08:12
                            > > Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??
                            > >
                            > >
                            > >
                            > >
                            > >
                            > > Nando.
                            > >
                            > > Many thanks for your detailed reply.
                            > >
                            > > The ELC is all wrong as you said, I traced the PCB, drew a schematic with ExpressPCB and uploaded a GIF image of the result in the photos, must remember to put a strong warning there so nobody thinks it is good and tries to make one!!
                            > >
                            > > I can not see it detects zero crossing at all, only the rectified DC-supply voltage to the ELC itself.
                            > >
                            > > The big load switching semiconductor is a TRIAC, infinite resistance between MT1 and MT2 both ways and approx. 100ohms gate to MT1. The MOC3020 is an instant switching Opto-TRIAC.
                            > >
                            > > I have one or two old ELCs I once made lying around, they were originally designed for a bit more power, 10-30kW, have 15 fixed zero switching ON/OFF loads and one variable phase controlled load which was 2x bigger than the fixed loads.
                            > >
                            > > The fixed loads turn on one by one (count up) if the variable load is at more than 75% and they turn off (count down) if the variable load is less than 25%.
                            > >
                            > > In this case it should be enough to have 4x500W fixed loads and one 1000W variable. (Of course it would be fun to mount 15x200W old light bulbs in a row as loads and and have two parallel bulbs as the variable. Unfortunately that would not last long enough !!)
                            > >
                            > > The pipe is another problem, the turbine maker put a 2" pipe thread on the input so that explains the very narrow short section at the turbine.
                            > >
                            > > The jet diameter is unknown to me, from the picture I took it looks like it may be about 30mm. Is that all right ?
                            > >
                            > > Then there is the wheel, it somehow does not look quite right, the Hartvigsen Hydro spoons look so much better :-)
                            > >
                            > > I also noticed in the picture of the wheel that the bearings seem to be ordinary sealed ball bearings mounted right inside the water chamber with no additional seals and no means of lubrication. That surely will be a problem very soon.
                            > >
                            > > I am afraid there are quite a few things to do before this one works properly .
                            > >
                            > > Best regards.
                            > >
                            > > Thor.
                            > >
                            > > --- In microhydro@yahoogroups.com, "Nando" <nando37@> wrote:
                            > > >
                            > > > Thor :
                            > > >
                            > > > The ELC is a common PWM voltage regulator in reverse mode, this means that it is reading the rectified output voltage and if is higher than the reference starts to PWM modulate the power resistor to bring the voltage down via 50 HZ phase loading.
                            > > >
                            > > > This regulator is poor, the TL494 is the equivalent to the SG3825 family and has a wrong use.
                            > > >
                            > > > The TL494 has two amplifiers, one defined for current detection that can be used to detect the Zero crossing but due to the oscillator circuit the detector requires a clamp to limit the behavior of the oscillator lower transitional and keep the saw tooth working properly, and the second amplifier to detect the voltage fluctuations to turn ON the output pulse for the TRIAC ON position in the 180 degrees angle of the sine wave.
                            > > >
                            > > > This design is better for a Vdc control and I may wonder if the TRIAC is not a TRIAC but a MosFet -- does the device have a heat sink dissipator ?. Can you read the voltage that triggers the device to see if it is 12 volts with a width time equal to less than 180 degrees or around 2 or 3 volts ( if it is a TRIAC).
                            > > >
                            > > > The ELC in this case would have been better using two 555 IC, one as a Cero crossing point trigger with the time constant varied by the rectified voltage to trigger the second 555 to give a 30 or so microseconds pulse to turn the Triac ON phase wise, from the 180 degrees backwards incremented. -- This I did shortly after the 555 appeared in the market converting an equivalent circuit using a lot of discrete parts .
                            > > >
                            > > > Basically the ELC needs a cero crossing detector to trigger or reset an saw tooth oscillator with the amplitude of the saw tooth varied by the variable AC voltage ( rectified and slightly filtered) to cross the upper trigger point prior the reaching of the 50 Hz ( 20 ms) 180 degrees crossing to trigger the second 555 to generate the 30 or so microseconds to trigger the triac.
                            > > >
                            > > > We also need an amplifier to be able to modulate the saw tooth against a voltage reference.
                            > > >
                            > > > There is a need of a good motor Running Capacitor , connected in parallel to the generator ) to reduce the sine wave distortion that the TRIAC ON pulses generate.
                            > > >
                            > > > The head needed is defined by the PCD diameter of the turbine and the frequency to give the peripheral velocity of the turbine.
                            > > >
                            > > > The dynamic pressure drops too much !!
                            > > >
                            > > > The 40 meters 84 mm diameter is presenting too much water friction !! The 1 meter long 70 mm diameter is reducing the water volume too much !!
                            > > >
                            > > > To determine the HEAD
                            > > >
                            > > > So for a 1500 RPM turbine the RPS is 1500/60 sec = 25 RPS
                            > > >
                            > > > H= Head
                            > > >
                            > > > 25 RPS * pi * Diameter turbine
                            > > >
                            > > > 25 * 3.14 * 0.19 = 14,92 m/s
                            > > >
                            > > > Vjet = 100/49* 14,92= 30,45 m/s
                            > > >
                            > > > 30,45 ^2 = 2 * 9,81 * H where H = 47,27m/s Which is close to the reported : about 50 meters static ,
                            > > >
                            > > > For a 3 KW the ELC should control two - 1 KW full ON/OFF loads plus the primary phase controlled 1 KW load as a minimum for best operation, though I would make the ELC differently and in this case a primary phase loaded 500 watts, a second full ON/OFF 500 watts , then 2 - 1 KW each load to have a full complement loading , this if the maximum power is 3 KW, though I would suggest the last 1 KW load to be a 1,5 KW load in case that the generator can produce more than 3 KW.
                            > > >
                            > > > Nando
                            > > >
                            > > > ----- Original Message -----
                            > > > From: Thor
                            > > > To: microhydro@yahoogroups.com
                            > > > Sent: Tuesday, July 31, 2012 16:51
                            > > > Subject: [microhydro] Does Someone know this Turbine-Generator-ELC ??
                            > > >
                            > > >
                            > > >
                            > > > Hi everybody.
                            > > >
                            > > > First I was only going to ask if anybody had seen the ELC in the pictures I posted, but then decided to tell the full story as I far as I know it.
                            > > >
                            > > > I have been asked for help to get this Micro Hydro setup running properly. It was ordered and installed last year but so far almost nothing has worked as expected.
                            > > >
                            > > > Today I visited the site and took some pictures and measurements, (see group photos, album China-Turbine-In-Iceland http://groups.yahoo.com/group/microhydro/photos/album/1255983797/pic/list.
                            > > >
                            > > > The total head is approx. 50m, the static pressure with no flow is 4.8bar which drops to 3.0 bar at maximum needle valve opening.
                            > > >
                            > > > There is plenty of water, the pipe is always full.
                            > > >
                            > > > I was told the upper part of the penstock is 200m long HDPE pipe 110/6mm (internal dia. 108mm)
                            > > > The lower part is 40m long HDPE 90/8mm (internal dia. 84mm)
                            > > > there is also a short (1m long, less than 70mm dia.?) steel pipe where the penstock connects to the turbine.
                            > > >
                            > > > They ordered and got a turbine/generator rated for 50Hz/230V/3kW, 1500rpm at 40m head. It was known that the pipe would limit the flow and they did expect to run at approx. 80% pressure.
                            > > >
                            > > > First problem: The turbine did not come with a needle valve, just a far too wide fixed nozzle, so the owners made one, rather difficult to turn, but does not leak and seems to work all right.
                            > > >
                            > > > Second problem: slip ring damage.
                            > > > The generator is single phase with 2 slip rings and 2 brushes on each ring. The brush holders are made from thin sheet metal, the brushes are very loose and originally they were positioned some 15-20mm away from the rings so the brushes got stuck in the holders with arcing and ring damage. The rings have been repaired and the position of brush holders has been fixed somewhat, but it is still not good.
                            > > >
                            > > > Third problem: The ELC has never worked properly. It has a single 3kW dump load controlled by a TRIAC. It senses the voltage and fortunately the generator seems properly made to give 220-230V at 50Hz.
                            > > > But the ELC does not work smoothly, it either diverts no power to the dump load or far too much so the voltage and speed are just fluctuating wildly 170-240V 40-55Hz. The ELC has IC TL494CN which controls the TRIAC via MOC3020 Optocoupler. The TRIAC is unknown. The manufacturer used grinder on all the markings but failed to delete the IC´s :-)
                            > > >
                            > > > Fourth problem: The power output is much lower than expected, it seems to be at maximum running at 3.6bar pressure but then it is only approx. 5.6A x 230V = 1.3kW
                            > > > We measured the last one at 50Hz, it is a bit more if we lower speed and voltage, 40Hz 170V 12.1A = 2.1kW
                            > > >
                            > > > By measuring the distance from nozzle to shaft it looks like effective diameter of wheel is approx. 190mm. I think that is a bit too big for 1500rpm at 40m head.
                            > > >
                            > > > Any information regarding this appreciated.
                            > > >
                            > > > Best regards.
                            > > >
                            > > > Thor.
                            > > > (Electronics technician and a long time lurker in this group)
                            > > >
                            > > >
                            > > >
                            > > >
                            > > >
                            > > > [Non-text portions of this message have been removed]
                            > > >
                            > >
                            > >
                            > >
                            > >
                            > >
                            > > [Non-text portions of this message have been removed]
                            > >
                            >
                            > [Non-text portions of this message have been removed]
                            >
                            >
                            >
                            >
                            >
                            > [Non-text portions of this message have been removed]
                            >
                          • Nando
                            THOR: Start by using two large size Mosfets, like 600 V breakdown and 30 or 40 amps also find the cases that are insulated that do not need to have additional
                            Message 13 of 15 , Aug 4, 2012
                            • 0 Attachment
                              THOR:

                              Start by using two large size Mosfets, like 600 V breakdown and 30 or 40
                              amps also find the cases that are insulated that do not need to have
                              additional insulation parts.

                              I started using them as AC Mosfets shortly after the high voltage Mosfets
                              appeared in the market -- several decades ago !!.

                              You need to supply isolated pulses and depending on the circuit you can
                              provide 100 % ON time , also you can use PWM to control the % of time ON
                              desired.

                              I have used a push-pull transformer and the secondary either a single
                              winding with a full wave rectifier with a small resistors connected to the
                              Sources and the gates to turn the two Mosfets ON at the same time , The
                              primary pulses ON from 0 To 50 % ( alternating) to control the PWM into the
                              mosfets , The secondary may as well have additional circuitry to turn the
                              MosFets OFF fast.

                              Also I have used other types of control with semiconductors if I have
                              additional floating 12 or so volts to attach to the Sources and the gates
                              controlled by the devices like fast optocouplers etc.

                              I have designed high power DC/AC or DC/DC units with high-power capabilities
                              into several kws ranges.

                              Nando



                              ----- Original Message -----
                              From: Thor
                              To: microhydro@yahoogroups.com
                              Sent: Saturday, August 04, 2012 06:29
                              Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??





                              Nando.

                              Now you got me confused for a moment (AC type Mosfet? and ...drains are in parallel with the generator...??) - no problem now I know what you are saying.

                              I have never actually used MOSFETs for AC-switching - only Thyristor or TRIAC SSRs - but Google helped me back on track.

                              This diagram I found shows the principle.
                              http://easy-electronics4u.blogspot.com/2012/02/switch-ac-loads-using-mosfets-as-relay.html

                              The "dump load" in the diagram is the 10k resistor and LEDs.

                              Both MOSFETs are N-Channel and they conduct (D-S) in both directions when turned ON by applying positive G-S voltage. However we must connect two in series because of the parasitic D-S diode in the MOSFETs.

                              In the real world we also have to take care of a couple of more things.

                              - The MOSFETs must be mounted with insulation on a suitably large heatsink.

                              - MOSFETs must be turned ON/OFF very fast so they do not heat up and burn (the 7400 in the diagram I mentioned will not be sufficiently fast if the D-S current is high) and they must also be fully OFF (or fully ON) during power-up and power-down - dedicated Driver ICs exist and could be used.

                              - The Gate Driver Circuit must have isolated power supply (transformer) and it should also be isolated from the actual control circuit (Opto-coupler).

                              The driver supply can be a low power 10-15V DC with a low ESR capacitor just to make sure we have enough gate current to charge the gate capacitance and turn the MOSFETs ON/OFF fast enough - this gate current is surprisingly high but only for microseconds.

                              Then one question:
                              Has some manufacturer made a High Voltage (>230V) High Current (>10A) Fast Switching (>20kHz) MOSFET Solid State Relay for AC with all these functions inside?
                              It would be a very useful building block for ELC but I can only find small ones like http://www.anglia.com/newsarchive/2233.asp?article_id=3005.
                              (They call it "High Current" but that is 0.2A!!)

                              Best regards.

                              Thor.

                              --- In microhydro@yahoogroups.com, "Nando" <nando37@...> wrote:
                              >
                              > I need to add that the Mosfet has to be the AC type which means two mosfets connected source to source and gates together and the Drains are in parallel with the generator of course one of the drains having a ballast load and the ckt oscillator around 10-15 KHZ with proper Vac isolation .
                              >
                              > Nando
                              >
                              >
                              > ----- Original Message -----
                              > From: Nando
                              > To: microhydro@yahoogroups.com
                              > Sent: Friday, August 03, 2012 11:04
                              > Subject: Re: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??
                              >
                              >
                              >
                              > Michael:
                              >
                              > The circuit fails because it is using a Triac and the circuit if you examine it carefully will see that just a comparator is used and for that purpose a power Mosfet is needed and not a TRIAC plus a ballast load to load the generator to reduce the DC voltage depending on the time constant of the storage capacitor prior to the Voltage regulator ( 12 volts ) .
                              >
                              > The circuit make work if the Triac is replaced with a high Voltage Mosfet with a ballast equal to close the peak power and the filter in the rectified circuit is set to have certain low voltage.
                              >
                              > I have used this type of circuit to regulate induction motor as generators using the sine wave rectified with an independent time constant for the PWM to operate properly.
                              >
                              > Nando
                              >
                              > ----- Original Message -----
                              > From: Michael
                              > To: microhydro@yahoogroups.com
                              > Sent: Friday, August 03, 2012 09:32
                              > Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??
                              >
                              > Hello,
                              > in relation to the controller, which you guys say doesnt work:
                              > My question is,
                              > is the concept viable? In the schematic Thor has drawn, the generator voltage is the feedback input to the PWM ic, so they are attempting to regulate the generator voltage. Done properly would it work, i.e to use a PWM chip to control the load on a generator to keep the generator voltage constant? For example if the voltage was rectified to DC, and smoothed, could the PWM output switch on a load, and control load.
                              >
                              > Michael.
                              >
                              > --- In microhydro@yahoogroups.com, "Nando" <nando37@> wrote:
                              > >
                              > > THOR:
                              > >
                              > > You got the rest of the analysis and the idea of your ELC is not practical
                              > >
                              > > The ELC with 15 loads, you just need for easy control of 3 KW , to have 6 loads of 500 watts and the one used as Phase control to be also 500 watts -- it is an error to use a double load there .
                              > >
                              > > Also use a 10 microfarad motor RUNNING CAPACITOR in parallel with the power lines to reduce the Triac variable phase On pulses distortion it generates,
                              > >
                              > > Do not use lamps as active ballast loads it is expensive if the lamps blow.
                              > >
                              > > I have not tried to calculate the nozzle diameter because the information has too many errors and it is a waste of time to define what the nozzle is, though we could calculate the water volume to produce 3 KW with a well defined head which you do not have due to the bad pipes installed.
                              > >
                              > > Assuming you have a net 45 meter head and 3 KW the water volume would be 3000= 45 *6 * Vol ; Vol= 11.1 liter/sec
                              > >
                              > > Vjet = Sq-rt( 2 * 9,81 * 45) = 29,71,4 m/s = 2971,4 cms/sc
                              > >
                              > > Jet Area = 11100/ 2971,4 = 3,7356 cms^2
                              > >
                              > > Jet dia = 2* Sq-rt ( 3,7356/3.14) = 2,18 cms diameter
                              > >
                              > > Nando
                              > >
                              > >
                              > >
                              > > ----- Original Message -----
                              > > From: Thor
                              > > To: microhydro@yahoogroups.com
                              > > Sent: Thursday, August 02, 2012 08:12
                              > > Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??
                              > >
                              > >
                              > >
                              > >
                              > >
                              > > Nando.
                              > >
                              > > Many thanks for your detailed reply.
                              > >
                              > > The ELC is all wrong as you said, I traced the PCB, drew a schematic with ExpressPCB and uploaded a GIF image of the result in the photos, must remember to put a strong warning there so nobody thinks it is good and tries to make one!!
                              > >
                              > > I can not see it detects zero crossing at all, only the rectified DC-supply voltage to the ELC itself.
                              > >
                              > > The big load switching semiconductor is a TRIAC, infinite resistance between MT1 and MT2 both ways and approx. 100ohms gate to MT1. The MOC3020 is an instant switching Opto-TRIAC.
                              > >
                              > > I have one or two old ELCs I once made lying around, they were originally designed for a bit more power, 10-30kW, have 15 fixed zero switching ON/OFF loads and one variable phase controlled load which was 2x bigger than the fixed loads.
                              > >
                              > > The fixed loads turn on one by one (count up) if the variable load is at more than 75% and they turn off (count down) if the variable load is less than 25%.
                              > >
                              > > In this case it should be enough to have 4x500W fixed loads and one 1000W variable. (Of course it would be fun to mount 15x200W old light bulbs in a row as loads and and have two parallel bulbs as the variable. Unfortunately that would not last long enough !!)
                              > >
                              > > The pipe is another problem, the turbine maker put a 2" pipe thread on the input so that explains the very narrow short section at the turbine.
                              > >
                              > > The jet diameter is unknown to me, from the picture I took it looks like it may be about 30mm. Is that all right ?
                              > >
                              > > Then there is the wheel, it somehow does not look quite right, the Hartvigsen Hydro spoons look so much better :-)
                              > >
                              > > I also noticed in the picture of the wheel that the bearings seem to be ordinary sealed ball bearings mounted right inside the water chamber with no additional seals and no means of lubrication. That surely will be a problem very soon.
                              > >
                              > > I am afraid there are quite a few things to do before this one works properly .
                              > >
                              > > Best regards.
                              > >
                              > > Thor.
                              > >
                              > > --- In microhydro@yahoogroups.com, "Nando" <nando37@> wrote:
                              > > >
                              > > > Thor :
                              > > >
                              > > > The ELC is a common PWM voltage regulator in reverse mode, this means that it is reading the rectified output voltage and if is higher than the reference starts to PWM modulate the power resistor to bring the voltage down via 50 HZ phase loading.
                              > > >
                              > > > This regulator is poor, the TL494 is the equivalent to the SG3825 family and has a wrong use.
                              > > >
                              > > > The TL494 has two amplifiers, one defined for current detection that can be used to detect the Zero crossing but due to the oscillator circuit the detector requires a clamp to limit the behavior of the oscillator lower transitional and keep the saw tooth working properly, and the second amplifier to detect the voltage fluctuations to turn ON the output pulse for the TRIAC ON position in the 180 degrees angle of the sine wave.
                              > > >
                              > > > This design is better for a Vdc control and I may wonder if the TRIAC is not a TRIAC but a MosFet -- does the device have a heat sink dissipator ?. Can you read the voltage that triggers the device to see if it is 12 volts with a width time equal to less than 180 degrees or around 2 or 3 volts ( if it is a TRIAC).
                              > > >
                              > > > The ELC in this case would have been better using two 555 IC, one as a Cero crossing point trigger with the time constant varied by the rectified voltage to trigger the second 555 to give a 30 or so microseconds pulse to turn the Triac ON phase wise, from the 180 degrees backwards incremented. -- This I did shortly after the 555 appeared in the market converting an equivalent circuit using a lot of discrete parts .
                              > > >
                              > > > Basically the ELC needs a cero crossing detector to trigger or reset an saw tooth oscillator with the amplitude of the saw tooth varied by the variable AC voltage ( rectified and slightly filtered) to cross the upper trigger point prior the reaching of the 50 Hz ( 20 ms) 180 degrees crossing to trigger the second 555 to generate the 30 or so microseconds to trigger the triac.
                              > > >
                              > > > We also need an amplifier to be able to modulate the saw tooth against a voltage reference.
                              > > >
                              > > > There is a need of a good motor Running Capacitor , connected in parallel to the generator ) to reduce the sine wave distortion that the TRIAC ON pulses generate.
                              > > >
                              > > > The head needed is defined by the PCD diameter of the turbine and the frequency to give the peripheral velocity of the turbine.
                              > > >
                              > > > The dynamic pressure drops too much !!
                              > > >
                              > > > The 40 meters 84 mm diameter is presenting too much water friction !! The 1 meter long 70 mm diameter is reducing the water volume too much !!
                              > > >
                              > > > To determine the HEAD
                              > > >
                              > > > So for a 1500 RPM turbine the RPS is 1500/60 sec = 25 RPS
                              > > >
                              > > > H= Head
                              > > >
                              > > > 25 RPS * pi * Diameter turbine
                              > > >
                              > > > 25 * 3.14 * 0.19 = 14,92 m/s
                              > > >
                              > > > Vjet = 100/49* 14,92= 30,45 m/s
                              > > >
                              > > > 30,45 ^2 = 2 * 9,81 * H where H = 47,27m/s Which is close to the reported : about 50 meters static ,
                              > > >
                              > > > For a 3 KW the ELC should control two - 1 KW full ON/OFF loads plus the primary phase controlled 1 KW load as a minimum for best operation, though I would make the ELC differently and in this case a primary phase loaded 500 watts, a second full ON/OFF 500 watts , then 2 - 1 KW each load to have a full complement loading , this if the maximum power is 3 KW, though I would suggest the last 1 KW load to be a 1,5 KW load in case that the generator can produce more than 3 KW.
                              > > >
                              > > > Nando
                              > > >
                              > > > ----- Original Message -----
                              > > > From: Thor
                              > > > To: microhydro@yahoogroups.com
                              > > > Sent: Tuesday, July 31, 2012 16:51
                              > > > Subject: [microhydro] Does Someone know this Turbine-Generator-ELC ??
                              > > >
                              > > >
                              > > >
                              > > > Hi everybody.
                              > > >
                              > > > First I was only going to ask if anybody had seen the ELC in the pictures I posted, but then decided to tell the full story as I far as I know it.
                              > > >
                              > > > I have been asked for help to get this Micro Hydro setup running properly. It was ordered and installed last year but so far almost nothing has worked as expected.
                              > > >
                              > > > Today I visited the site and took some pictures and measurements, (see group photos, album China-Turbine-In-Iceland http://groups.yahoo.com/group/microhydro/photos/album/1255983797/pic/list.
                              > > >
                              > > > The total head is approx. 50m, the static pressure with no flow is 4.8bar which drops to 3.0 bar at maximum needle valve opening.
                              > > >
                              > > > There is plenty of water, the pipe is always full.
                              > > >
                              > > > I was told the upper part of the penstock is 200m long HDPE pipe 110/6mm (internal dia. 108mm)
                              > > > The lower part is 40m long HDPE 90/8mm (internal dia. 84mm)
                              > > > there is also a short (1m long, less than 70mm dia.?) steel pipe where the penstock connects to the turbine.
                              > > >
                              > > > They ordered and got a turbine/generator rated for 50Hz/230V/3kW, 1500rpm at 40m head. It was known that the pipe would limit the flow and they did expect to run at approx. 80% pressure.
                              > > >
                              > > > First problem: The turbine did not come with a needle valve, just a far too wide fixed nozzle, so the owners made one, rather difficult to turn, but does not leak and seems to work all right.
                              > > >
                              > > > Second problem: slip ring damage.
                              > > > The generator is single phase with 2 slip rings and 2 brushes on each ring. The brush holders are made from thin sheet metal, the brushes are very loose and originally they were positioned some 15-20mm away from the rings so the brushes got stuck in the holders with arcing and ring damage. The rings have been repaired and the position of brush holders has been fixed somewhat, but it is still not good.
                              > > >
                              > > > Third problem: The ELC has never worked properly. It has a single 3kW dump load controlled by a TRIAC. It senses the voltage and fortunately the generator seems properly made to give 220-230V at 50Hz.
                              > > > But the ELC does not work smoothly, it either diverts no power to the dump load or far too much so the voltage and speed are just fluctuating wildly 170-240V 40-55Hz. The ELC has IC TL494CN which controls the TRIAC via MOC3020 Optocoupler. The TRIAC is unknown. The manufacturer used grinder on all the markings but failed to delete the IC´s :-)
                              > > >
                              > > > Fourth problem: The power output is much lower than expected, it seems to be at maximum running at 3.6bar pressure but then it is only approx. 5.6A x 230V = 1.3kW
                              > > > We measured the last one at 50Hz, it is a bit more if we lower speed and voltage, 40Hz 170V 12.1A = 2.1kW
                              > > >
                              > > > By measuring the distance from nozzle to shaft it looks like effective diameter of wheel is approx. 190mm. I think that is a bit too big for 1500rpm at 40m head.
                              > > >
                              > > > Any information regarding this appreciated.
                              > > >
                              > > > Best regards.
                              > > >
                              > > > Thor.
                              > > > (Electronics technician and a long time lurker in this group)
                              > > >
                              > > >
                              > > >
                              > > >
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                            • Nando
                              THOR: I failed to respond to your question. Those devices are for a long current low speed service, therefore one can make out your own AC MosFet using the
                              Message 14 of 15 , Aug 4, 2012
                              • 0 Attachment
                                THOR:

                                I failed to respond to your question.

                                Those devices are for a long current low speed service, therefore one can make out your own AC MosFet using the large high voltage and high current mosfets , two in series or to buy the dual devices that some manufacturers make like Ixys
                                As an example search for IXYS product FMK 75-01F . 100 VOLTS, 75 AMPS & RDSon = 18 MILLIOHMS.
                                Or the LKK 47-06C5 With Isolated package Vdss= 600 V, I = 47 Amps, Rdson/mosfet = 45 milliohms

                                I have not used those package mosfets you comment : Solid State Relay for high Frequency .

                                Nando


                                ----- Original Message -----
                                From: Thor
                                To: microhydro@yahoogroups.com
                                Sent: Saturday, August 04, 2012 06:29
                                Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??





                                Nando.

                                Now you got me confused for a moment (AC type Mosfet? and ...drains are in parallel with the generator...??) - no problem now I know what you are saying.

                                I have never actually used MOSFETs for AC-switching - only Thyristor or TRIAC SSRs - but Google helped me back on track.

                                This diagram I found shows the principle.
                                http://easy-electronics4u.blogspot.com/2012/02/switch-ac-loads-using-mosfets-as-relay.html

                                The "dump load" in the diagram is the 10k resistor and LEDs.

                                Both MOSFETs are N-Channel and they conduct (D-S) in both directions when turned ON by applying positive G-S voltage. However we must connect two in series because of the parasitic D-S diode in the MOSFETs.

                                In the real world we also have to take care of a couple of more things.

                                - The MOSFETs must be mounted with insulation on a suitably large heatsink.

                                - MOSFETs must be turned ON/OFF very fast so they do not heat up and burn (the 7400 in the diagram I mentioned will not be sufficiently fast if the D-S current is high) and they must also be fully OFF (or fully ON) during power-up and power-down - dedicated Driver ICs exist and could be used.

                                - The Gate Driver Circuit must have isolated power supply (transformer) and it should also be isolated from the actual control circuit (Opto-coupler).

                                The driver supply can be a low power 10-15V DC with a low ESR capacitor just to make sure we have enough gate current to charge the gate capacitance and turn the MOSFETs ON/OFF fast enough - this gate current is surprisingly high but only for microseconds.

                                Then one question:
                                Has some manufacturer made a High Voltage (>230V) High Current (>10A) Fast Switching (>20kHz) MOSFET Solid State Relay for AC with all these functions inside?
                                It would be a very useful building block for ELC but I can only find small ones like http://www.anglia.com/newsarchive/2233.asp?article_id=3005.
                                (They call it "High Current" but that is 0.2A!!)

                                Best regards.

                                Thor.

                                --- In microhydro@yahoogroups.com, "Nando" <nando37@...> wrote:
                                >
                                > I need to add that the Mosfet has to be the AC type which means two mosfets connected source to source and gates together and the Drains are in parallel with the generator of course one of the drains having a ballast load and the ckt oscillator around 10-15 KHZ with proper Vac isolation .
                                >
                                > Nando
                                >
                                >
                                > ----- Original Message -----
                                > From: Nando
                                > To: microhydro@yahoogroups.com
                                > Sent: Friday, August 03, 2012 11:04
                                > Subject: Re: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??
                                >
                                >
                                >
                                > Michael:
                                >
                                > The circuit fails because it is using a Triac and the circuit if you examine it carefully will see that just a comparator is used and for that purpose a power Mosfet is needed and not a TRIAC plus a ballast load to load the generator to reduce the DC voltage depending on the time constant of the storage capacitor prior to the Voltage regulator ( 12 volts ) .
                                >
                                > The circuit make work if the Triac is replaced with a high Voltage Mosfet with a ballast equal to close the peak power and the filter in the rectified circuit is set to have certain low voltage.
                                >
                                > I have used this type of circuit to regulate induction motor as generators using the sine wave rectified with an independent time constant for the PWM to operate properly.
                                >
                                > Nando
                                >
                                > ----- Original Message -----
                                > From: Michael
                                > To: microhydro@yahoogroups.com
                                > Sent: Friday, August 03, 2012 09:32
                                > Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??
                                >
                                > Hello,
                                > in relation to the controller, which you guys say doesnt work:
                                > My question is,
                                > is the concept viable? In the schematic Thor has drawn, the generator voltage is the feedback input to the PWM ic, so they are attempting to regulate the generator voltage. Done properly would it work, i.e to use a PWM chip to control the load on a generator to keep the generator voltage constant? For example if the voltage was rectified to DC, and smoothed, could the PWM output switch on a load, and control load.
                                >
                                > Michael.
                                >
                                > --- In microhydro@yahoogroups.com, "Nando" <nando37@> wrote:
                                > >
                                > > THOR:
                                > >
                                > > You got the rest of the analysis and the idea of your ELC is not practical
                                > >
                                > > The ELC with 15 loads, you just need for easy control of 3 KW , to have 6 loads of 500 watts and the one used as Phase control to be also 500 watts -- it is an error to use a double load there .
                                > >
                                > > Also use a 10 microfarad motor RUNNING CAPACITOR in parallel with the power lines to reduce the Triac variable phase On pulses distortion it generates,
                                > >
                                > > Do not use lamps as active ballast loads it is expensive if the lamps blow.
                                > >
                                > > I have not tried to calculate the nozzle diameter because the information has too many errors and it is a waste of time to define what the nozzle is, though we could calculate the water volume to produce 3 KW with a well defined head which you do not have due to the bad pipes installed.
                                > >
                                > > Assuming you have a net 45 meter head and 3 KW the water volume would be 3000= 45 *6 * Vol ; Vol= 11.1 liter/sec
                                > >
                                > > Vjet = Sq-rt( 2 * 9,81 * 45) = 29,71,4 m/s = 2971,4 cms/sc
                                > >
                                > > Jet Area = 11100/ 2971,4 = 3,7356 cms^2
                                > >
                                > > Jet dia = 2* Sq-rt ( 3,7356/3.14) = 2,18 cms diameter
                                > >
                                > > Nando
                                > >
                                > >
                                > >
                                > > ----- Original Message -----
                                > > From: Thor
                                > > To: microhydro@yahoogroups.com
                                > > Sent: Thursday, August 02, 2012 08:12
                                > > Subject: [microhydro] Re: Does Someone know this Turbine-Generator-ELC ??
                                > >
                                > >
                                > >
                                > >
                                > >
                                > > Nando.
                                > >
                                > > Many thanks for your detailed reply.
                                > >
                                > > The ELC is all wrong as you said, I traced the PCB, drew a schematic with ExpressPCB and uploaded a GIF image of the result in the photos, must remember to put a strong warning there so nobody thinks it is good and tries to make one!!
                                > >
                                > > I can not see it detects zero crossing at all, only the rectified DC-supply voltage to the ELC itself.
                                > >
                                > > The big load switching semiconductor is a TRIAC, infinite resistance between MT1 and MT2 both ways and approx. 100ohms gate to MT1. The MOC3020 is an instant switching Opto-TRIAC.
                                > >
                                > > I have one or two old ELCs I once made lying around, they were originally designed for a bit more power, 10-30kW, have 15 fixed zero switching ON/OFF loads and one variable phase controlled load which was 2x bigger than the fixed loads.
                                > >
                                > > The fixed loads turn on one by one (count up) if the variable load is at more than 75% and they turn off (count down) if the variable load is less than 25%.
                                > >
                                > > In this case it should be enough to have 4x500W fixed loads and one 1000W variable. (Of course it would be fun to mount 15x200W old light bulbs in a row as loads and and have two parallel bulbs as the variable. Unfortunately that would not last long enough !!)
                                > >
                                > > The pipe is another problem, the turbine maker put a 2" pipe thread on the input so that explains the very narrow short section at the turbine.
                                > >
                                > > The jet diameter is unknown to me, from the picture I took it looks like it may be about 30mm. Is that all right ?
                                > >
                                > > Then there is the wheel, it somehow does not look quite right, the Hartvigsen Hydro spoons look so much better :-)
                                > >
                                > > I also noticed in the picture of the wheel that the bearings seem to be ordinary sealed ball bearings mounted right inside the water chamber with no additional seals and no means of lubrication. That surely will be a problem very soon.
                                > >
                                > > I am afraid there are quite a few things to do before this one works properly .
                                > >
                                > > Best regards.
                                > >
                                > > Thor.
                                > >
                                > > --- In microhydro@yahoogroups.com, "Nando" <nando37@> wrote:
                                > > >
                                > > > Thor :
                                > > >
                                > > > The ELC is a common PWM voltage regulator in reverse mode, this means that it is reading the rectified output voltage and if is higher than the reference starts to PWM modulate the power resistor to bring the voltage down via 50 HZ phase loading.
                                > > >
                                > > > This regulator is poor, the TL494 is the equivalent to the SG3825 family and has a wrong use.
                                > > >
                                > > > The TL494 has two amplifiers, one defined for current detection that can be used to detect the Zero crossing but due to the oscillator circuit the detector requires a clamp to limit the behavior of the oscillator lower transitional and keep the saw tooth working properly, and the second amplifier to detect the voltage fluctuations to turn ON the output pulse for the TRIAC ON position in the 180 degrees angle of the sine wave.
                                > > >
                                > > > This design is better for a Vdc control and I may wonder if the TRIAC is not a TRIAC but a MosFet -- does the device have a heat sink dissipator ?. Can you read the voltage that triggers the device to see if it is 12 volts with a width time equal to less than 180 degrees or around 2 or 3 volts ( if it is a TRIAC).
                                > > >
                                > > > The ELC in this case would have been better using two 555 IC, one as a Cero crossing point trigger with the time constant varied by the rectified voltage to trigger the second 555 to give a 30 or so microseconds pulse to turn the Triac ON phase wise, from the 180 degrees backwards incremented. -- This I did shortly after the 555 appeared in the market converting an equivalent circuit using a lot of discrete parts .
                                > > >
                                > > > Basically the ELC needs a cero crossing detector to trigger or reset an saw tooth oscillator with the amplitude of the saw tooth varied by the variable AC voltage ( rectified and slightly filtered) to cross the upper trigger point prior the reaching of the 50 Hz ( 20 ms) 180 degrees crossing to trigger the second 555 to generate the 30 or so microseconds to trigger the triac.
                                > > >
                                > > > We also need an amplifier to be able to modulate the saw tooth against a voltage reference.
                                > > >
                                > > > There is a need of a good motor Running Capacitor , connected in parallel to the generator ) to reduce the sine wave distortion that the TRIAC ON pulses generate.
                                > > >
                                > > > The head needed is defined by the PCD diameter of the turbine and the frequency to give the peripheral velocity of the turbine.
                                > > >
                                > > > The dynamic pressure drops too much !!
                                > > >
                                > > > The 40 meters 84 mm diameter is presenting too much water friction !! The 1 meter long 70 mm diameter is reducing the water volume too much !!
                                > > >
                                > > > To determine the HEAD
                                > > >
                                > > > So for a 1500 RPM turbine the RPS is 1500/60 sec = 25 RPS
                                > > >
                                > > > H= Head
                                > > >
                                > > > 25 RPS * pi * Diameter turbine
                                > > >
                                > > > 25 * 3.14 * 0.19 = 14,92 m/s
                                > > >
                                > > > Vjet = 100/49* 14,92= 30,45 m/s
                                > > >
                                > > > 30,45 ^2 = 2 * 9,81 * H where H = 47,27m/s Which is close to the reported : about 50 meters static ,
                                > > >
                                > > > For a 3 KW the ELC should control two - 1 KW full ON/OFF loads plus the primary phase controlled 1 KW load as a minimum for best operation, though I would make the ELC differently and in this case a primary phase loaded 500 watts, a second full ON/OFF 500 watts , then 2 - 1 KW each load to have a full complement loading , this if the maximum power is 3 KW, though I would suggest the last 1 KW load to be a 1,5 KW load in case that the generator can produce more than 3 KW.
                                > > >
                                > > > Nando
                                > > >
                                > > > ----- Original Message -----
                                > > > From: Thor
                                > > > To: microhydro@yahoogroups.com
                                > > > Sent: Tuesday, July 31, 2012 16:51
                                > > > Subject: [microhydro] Does Someone know this Turbine-Generator-ELC ??
                                > > >
                                > > >
                                > > >
                                > > > Hi everybody.
                                > > >
                                > > > First I was only going to ask if anybody had seen the ELC in the pictures I posted, but then decided to tell the full story as I far as I know it.
                                > > >
                                > > > I have been asked for help to get this Micro Hydro setup running properly. It was ordered and installed last year but so far almost nothing has worked as expected.
                                > > >
                                > > > Today I visited the site and took some pictures and measurements, (see group photos, album China-Turbine-In-Iceland http://groups.yahoo.com/group/microhydro/photos/album/1255983797/pic/list.
                                > > >
                                > > > The total head is approx. 50m, the static pressure with no flow is 4.8bar which drops to 3.0 bar at maximum needle valve opening.
                                > > >
                                > > > There is plenty of water, the pipe is always full.
                                > > >
                                > > > I was told the upper part of the penstock is 200m long HDPE pipe 110/6mm (internal dia. 108mm)
                                > > > The lower part is 40m long HDPE 90/8mm (internal dia. 84mm)
                                > > > there is also a short (1m long, less than 70mm dia.?) steel pipe where the penstock connects to the turbine.
                                > > >
                                > > > They ordered and got a turbine/generator rated for 50Hz/230V/3kW, 1500rpm at 40m head. It was known that the pipe would limit the flow and they did expect to run at approx. 80% pressure.
                                > > >
                                > > > First problem: The turbine did not come with a needle valve, just a far too wide fixed nozzle, so the owners made one, rather difficult to turn, but does not leak and seems to work all right.
                                > > >
                                > > > Second problem: slip ring damage.
                                > > > The generator is single phase with 2 slip rings and 2 brushes on each ring. The brush holders are made from thin sheet metal, the brushes are very loose and originally they were positioned some 15-20mm away from the rings so the brushes got stuck in the holders with arcing and ring damage. The rings have been repaired and the position of brush holders has been fixed somewhat, but it is still not good.
                                > > >
                                > > > Third problem: The ELC has never worked properly. It has a single 3kW dump load controlled by a TRIAC. It senses the voltage and fortunately the generator seems properly made to give 220-230V at 50Hz.
                                > > > But the ELC does not work smoothly, it either diverts no power to the dump load or far too much so the voltage and speed are just fluctuating wildly 170-240V 40-55Hz. The ELC has IC TL494CN which controls the TRIAC via MOC3020 Optocoupler. The TRIAC is unknown. The manufacturer used grinder on all the markings but failed to delete the IC´s :-)
                                > > >
                                > > > Fourth problem: The power output is much lower than expected, it seems to be at maximum running at 3.6bar pressure but then it is only approx. 5.6A x 230V = 1.3kW
                                > > > We measured the last one at 50Hz, it is a bit more if we lower speed and voltage, 40Hz 170V 12.1A = 2.1kW
                                > > >
                                > > > By measuring the distance from nozzle to shaft it looks like effective diameter of wheel is approx. 190mm. I think that is a bit too big for 1500rpm at 40m head.
                                > > >
                                > > > Any information regarding this appreciated.
                                > > >
                                > > > Best regards.
                                > > >
                                > > > Thor.
                                > > > (Electronics technician and a long time lurker in this group)
                                > > >
                                > > >
                                > > >
                                > > >
                                > > >
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