Expand Messages
• This is the first of two responses to the reversibility of scope leads problem, where significant deviances exist, to later be shown as seemingly defying
Message 1 of 3 , Feb 21, 2012
This is the first of two responses to the reversibility of scope leads problem, where significant deviances exist, to later be shown as seemingly defying common sense. This answer was obtained when the question was posed in the engineering category.

Pioneering the Applications of Interphasal Resonances http://tech.groups.yahoo.com/group/teslafy/

To: harvich@...
Date: Monday, February 20, 2012, 7:54 PM

 Hello, harvich!The community has voted and picked the best answer to your question:Scoping question to determine if a circuit is series resonant?Think you'll agree with their choice? Go to your question to see.When you pick best answers, you get 3 points. So, next time, seize the opportunity while your questions are live! Thanks for sharing your question with the world!The Yahoo! Answers Team Get the Yahoo! Toolbar for one-click access to Yahoo! Answers..

• This is the better answer made from the physics category where I have reprinted it to show my opinion. Reply from tigger; I am employing dual channel scopings
Message 2 of 3 , Feb 21, 2012
This is the better answer made from the physics category where I have reprinted it to show my opinion.

I am employing dual channel scopings on three series resonances from an (alternator 3 phase) delta output. I understand that the common (smaller ground) leads on both probes must be joined so I have these on one side of the stator lines serving the delta circuit to be tested. This means that on one channel we are measuring the complete voltage across that delta phase, as the common is on one side and the probe lead is on the other side, both connected to stator lines. To measure the internal voltage rise made by the series resonant circuit I have the second channel scope probe lead connected to the middle of the LC load. I understand that if the circuit is resonant both of these larger and smaller amplitude signals will be in phase. DOES IT MATTER IN WHICH DIRECTION I CONNECT THE OUTER SENSOR TO MEASURE THE ACTUAL PHASE VOLTAGE,(provided the common grounds are kept connected) AND SHOULD I GET THE SAME RESULTS WHEN THE OUTER CONNECTIONS ARE REVERSED? Suppose for example I find that the inner voltage rise slightly lags the outer voltage. Will I get the same result when the outside lead connections are reversed?
• 1 week ago

## Best Answer - Chosen by Voters

I have had to read your description several times to understand it, but I think I have it now. I understand that you have a 3-phase delta-connected alternator connected to a delta load, one phase of which consists of a capacitor and inductor connected in series, forming a supposedly resonant circuit at the operating frequency. I assume that the source and load are not grounded at any point until the CRO is connected (its common input will be connected to the frame of the scope, and therefore grounded). This is an unusual arrangement, since alternators are usually star-connected with the star point grounded. If this latter arrangement actually describes your alternator, you MUST NOT connect the common of the scope to any point other than the star point. If you do so you will short-circuit one phase of the alternator or part of the load via the probe lead and the scope ground connection.

Assuming that both alternator and load are delta connected and not grounded except through the scope I will make the following points:-

1) the load can be modeled as a series LCR circuit in which the resistance is mainly that of the inductor. At resonance the circuit will be entirely resistive since the reactances of the cap and inductor will be equal and opposite. The voltages across the cap and the inductor will be approximately, but not exactly equal in magnitude. This is because their reactances will be equal in magnitude, but the impedance of the inductor will be slightly larger than that of the cap since the inductor contains the R element of the circuit.

2) At resonance the current in the load will be in phase with the phase voltage, but the voltage across L (VL) will lead, while that across C (Vc)will lag the phase voltage. This does not agree with your statement "I understand that if the circuit is resonant both of these larger and smaller amplitude signals will be in phase", which I understand as meaning that the phase voltage will be in phase with either Vc or VL.
{HDN comment; I have  done scopings before across the 666 machine using 14 gauge coils in its first embodiment and recorded that the resonant circuit CAN and DOES exhibit a resonant voltage rise very close in time to its outside delta generated voltage. Note after 5 min into the video http://youtu.be/cxolO9Zwbjk  (only 25 views!)

Scoping idiosyncrasies and resonant test of components. I will redo some tests today on this subject, but it may be true that the circuit must be loaded to be perfectly resonant, which doesnt make sense to me, since the empty loaded circuit should also be made resonant according to tuning, but once an inductive load in spatial proximity is brought into play, that in itself should imply that since the reactance of the sender was changed by mutual induction, it should also have a change of paired capacity to be now resonant to the loaded condition. However in the previous video the loads were attached by wire means made clear back in Dec 21, 2010, and inductive change of the source from the load should not occur in that instance, since the interphasal loading has been accomplished by wire means rather then by means of vicinity in space of tuned resonant circuits.]

3) When you reverse the connections to the lines the scope will continue to display the phase voltage (with reversed phase) on one channel, but will switch from Vc (or VL) to VL (or Vc) on the other. Since VC and VL are approximately equal if Xc and XL >> R, and are of approximately opposite phase, you will not see much difference on the screen. However, because R is mainly associated with L, there will be a small but probably noticeable difference attributable to the complex impedance of L and its consequent non-quadrature phase angle. This could be very noticeable if R is not very small compared with XL.
{HDN comment; I think that when the situation involves advanced phase rotation where every time you see the signal cycle up and down, one extra cycle from the air core influence made by the 666 machine has occurred, and this acts as a sort of phase rotation 'wind" or an actual ether wind in time that seemingly displaces the position of the resonant voltage in time with respect to its source voltage. If this were true then the position of voltage rise when the measurements are made in harmony or against this ether wind in time will show different results. This reminds one of the famous experiments with light whereby no ether wind can be detected. This was later explained by relativity. But here I have encountered a situation where by increasing the time ether wind by a considerable degree, a measurement may be made whereby the circuit shows itself to be completely reactive, but it is actually resonant by virtue of voltage rise. More of this later in the next video, but what I intend to do is construct a solitary resonance with the very least ether wind.}

Pioneering the Applications of Interphasal Resonances http://tech.groups.yahoo.com/group/teslafy/

To: harvich@...
Date: Monday, February 20, 2012, 8:03 PM

 Hello, harvich!The community has voted and picked the best answer to your question:Scoping question to determine if a circuit is series resonant?Think you'll agree with their choice? Go to your question to see.When you pick best answers, you get 3 points. So, next time, seize the opportunity while your questions are live! Thanks for sharing your question with the world!The Yahoo! Answers Team Get the Yahoo! Toolbar for one-click access to Yahoo! Answers..

• Hi Harvey, You might be better off using multi channel scope. Say a four channel scope for example. Then you can select A+B and select INVERT on one channel
Message 3 of 3 , Feb 21, 2012
Hi Harvey,
You might be better off using multi channel scope.  Say a four channel scope for example.
Then you can select A+B and select INVERT on one channel to get differential readings between the two probe tips.

Time synchronous readings can then  be made using the same technique, as your second effective channel becomes channels C+D with say D inverted.

If using analog scope, try to use "chopped" mode, rather than alternate mode, as relative time between traces can get mucked up by sweep hold off between triggers.

As to your question the stray capacitance between the earth line on the scope and external environment would likely be much higher than the active tip measuring cicuit.

So in my own opinion no you wont get the same readings .....depending on many factors though.  Plus as you state, the earth clip lines are all commoned up so you could easily short out phases.

Using the technique suggested above it is easy to check by reversing probes A & B whilst in "differential" mode to check measurement. Same for second effective channel C & D.

Good luck
Gerry

Sent: Wednesday, February 22, 2012 5:58 AM
Cc: Heinz

This is the better answer made from the physics category where I have reprinted it to show my opinion.

I am employing dual channel scopings on three series resonances from an (alternator 3 phase) delta output. I understand that the common (smaller ground) leads on both probes must be joined so I have these on one side of the stator lines serving the delta circuit to be tested. This means that on one channel we are measuring the complete voltage across that delta phase, as the common is on one side and the probe lead is on the other side, both connected to stator lines. To measure the internal voltage rise made by the series resonant circuit I have the second channel scope probe lead connected to the middle of the LC load. I understand that if the circuit is resonant both of these larger and smaller amplitude signals will be in phase. DOES IT MATTER IN WHICH DIRECTION I CONNECT THE OUTER SENSOR TO MEASURE THE ACTUAL PHASE VOLTAGE,(provided the common grounds are kept connected) AND SHOULD I GET THE SAME RESULTS WHEN THE OUTER CONNECTIONS ARE REVERSED? Suppose for example I find that the inner voltage rise slightly lags the outer voltage. Will I get the same result when the outside lead connections are reversed?
• 1 week ago

## Best Answer - Chosen by Voters

I have had to read your description several times to understand it, but I think I have it now. I understand that you have a 3-phase delta-connected alternator connected to a delta load, one phase of which consists of a capacitor and inductor connected in series, forming a supposedly resonant circuit at the operating frequency. I assume that the source and load are not grounded at any point until the CRO is connected (its common input will be connected to the frame of the scope, and therefore grounded). This is an unusual arrangement, since alternators are usually star-connected with the star point grounded. If this latter arrangement actually describes your alternator, you MUST NOT connect the common of the scope to any point other than the star point. If you do so you will short-circuit one phase of the alternator or part of the load via the probe lead and the scope ground connection.

Assuming that both alternator and load are delta connected and not grounded except through the scope I will make the following points:-

1) the load can be modeled as a series LCR circuit in which the resistance is mainly that of the inductor. At resonance the circuit will be entirely resistive since the reactances of the cap and inductor will be equal and opposite. The voltages across the cap and the inductor will be approximately, but not exactly equal in magnitude. This is because their reactances will be equal in magnitude, but the impedance of the inductor will be slightly larger than that of the cap since the inductor contains the R element of the circuit.

2) At resonance the current in the load will be in phase with the phase voltage, but the voltage across L (VL) will lead, while that across C (Vc)will lag the phase voltage. This does not agree with your statement "I understand that if the circuit is resonant both of these larger and smaller amplitude signals will be in phase", which I understand as meaning that the phase voltage will be in phase with either Vc or VL.
{HDN comment; I have  done scopings before across the 666 machine using 14 gauge coils in its first embodiment and recorded that the resonant circuit CAN and DOES exhibit a resonant voltage rise very close in time to its outside delta generated voltage. Note after 5 min into the video http://youtu.be/cxolO9Zwbjk  (only 25 views!)

Scoping idiosyncrasies and resonant test of components. I will redo some tests today on this subject, but it may be true that the circuit must be loaded to be perfectly resonant, which doesnt make sense to me, since the empty loaded circuit should also be made resonant according to tuning, but once an inductive load in spatial proximity is brought into play, that in itself should imply that since the reactance of the sender was changed by mutual induction, it should also have a change of paired capacity to be now resonant to the loaded condition. However in the previous video the loads were attached by wire means made clear back in Dec 21, 2010, and inductive change of the source from the load should not occur in that instance, since the interphasal loading has been accomplished by wire means rather then by means of vicinity in space of tuned resonant circuits.]

3) When you reverse the connections to the lines the scope will continue to display the phase voltage (with reversed phase) on one channel, but will switch from Vc (or VL) to VL (or Vc) on the other. Since VC and VL are approximately equal if Xc and XL
>> R, and are of approximately opposite phase, you will not see much
difference on the screen. However, because R is mainly associated with L, there will be a small but probably noticeable difference attributable to the complex impedance of L and its consequent non-quadrature phase angle. This could be very noticeable if R is not very small compared with XL.
{HDN comment; I think that when the situation involves advanced phase rotation where every time you see the signal cycle up and down, one extra cycle from the air core influence made by the 666 machine has occurred, and this acts as a sort of phase rotation 'wind" or an actual ether wind in time that seemingly displaces the position of the resonant voltage in time with respect to its source voltage. If this were true then the position of voltage rise when the measurements are made in harmony or against this ether wind in time will show different results. This reminds one of the famous experiments with light whereby no ether wind can be detected. This was later explained by relativity. But here I have encountered a situation where by increasing the time ether wind by a considerable degree, a measurement may be made whereby the circuit shows itself to be completely reactive, but it is actually resonant by virtue of voltage rise. More of this later in the next video, but what I intend to do is construct a solitary resonance with the very least ether wind.}

Pioneering the Applications of Interphasal Resonances http://tech.groups.yahoo.com/group/teslafy/