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Re: neutral currents (II) Re: [usa-tesla] Question For The Group

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  • joesmith@cvctx.com
    I can t answer your question but I CAN say from drilling many,many,oil wells.The pipe or drill string is VERY highely magnetized. Joe in Texas Quoting Mark
    Message 1 of 19 , Jan 1, 2010

      I can't answer your question but I CAN say from drilling many,many,oil wells.The pipe or drill string is VERY highely magnetized.

      Joe in Texas


      Quoting Mark Jordan :
       

      Hi Bert,
       
      Thanks for the explanation. I have seen neutral failures in structures. The result was 140 volts on one leg and 90 on the other. The resident lost electronics in that failure. In that particular case, the ground wire was broken also. While I am not an electrician, I do a lot of troubleshooting and work on any electrical appliance or system in the average house today. I also study electrogalvanic corrosion and have been talking with the state agency that regulates the oil and gas industries here in Texas. I am wondering what happens to current when it grounds in the typical oilwell.
       
      Do you have any good idea where the neutral currents eventually end up? Considering that the current is nearly constant, if that current is earthed at some end point, it should be flowing through said earth? As such, potential differences between deeper layers of soils and other adjacent soils might result in capacitance?
       
      Mark S. Jordan
       
       


      --- On Tue, 12/29/09, Bert Hickman aquila.net> wrote:

      From: Bert Hickman aquila.net>
      Subject: Re: neutral currents (II) Re: [usa-tesla] Question For The Group
      To: usa-tesla@yahoogrou ps.com
      Date: Tuesday, December 29, 2009, 11:25 PM

       
      Hi Mark,

      Mark Jordan wrote:
      >
      >
      > Hi Dave, Michael and all,
      >
      > As far as I can tell to date, the neutral current is simply grounded
      > into the earth at the substations? The neutral wires themselves are also
      > attached to ground stations at nearly every pole and meter. What I don't
      > understand is why the neutral carries the current but the ground wire at
      > the meter does not. For example, I measure over 4 amps of current in the
      > neutral in a small structure with a 100 amp service. Since the 240 volt
      > appliances are not involved with the neutral, this return current is
      > coming from the common leg of the 120 volt appliances. Why wouldn't I
      > measure any current in the ground wire since it is connected to the
      > neutral also? I suspect this is because of the potential of the neutral
      > circuit is greater, as considered from any point, while the ground wire
      > represents a higher resistance? That could only indicate that a better
      > earthed ground is available somewhere between that structure and the
      > substation or at the substation itself?

      In MOST power transmission and distribution systems, earthing is done
      primarily for safety reasons. For example, a substation will have a VERY
      extensive earth grounding system that extends outward in all directions
      from the actual substation itself. This is done so that an accidental
      short circuit from a phase to ground, a surge from a nearby lightning
      strike, or other abnormal/fault conditions not introduce dangerous
      potentials between grounded pieces of equipment, or across short
      distances across the earth. Without the extensive grounding system, a
      fault to ground could cause dangerous potential differences that could
      result in electrocution of personnel inside or near the substation.

      In the above systems, supply and return currents flow through dedicated
      wires and NOT through the earth ground. In a Delta connection, the
      system is designed so that ALL of the current flows normally through the
      three phase wires. In a WYE system, a fourth wire (the neutral) handles
      any load imbalances between the three phase wires, and it's normally
      also connected to ground. HVAC power transmission systems use Delta
      connection with a high impedance connection to ground.

      In the US, private residences are usually fed by a single phase circuit.
      This is driven by a single phase, and the power is provided from the
      center-tapped output of a step-down distribution transformer. The outer
      legs of the secondary winding provide 240 VAC. Either leg to the center
      tap provides 120 VAC circuits. The center tap is the neutral. It's
      grounded at the service entrance (electric meter) and at the
      distribution transformer for safety. In a properly designed (and load
      balanced) residential distribution system, MOST of the current is
      provided by the outer legs. Any current imbalance (usually relatively
      small) is conducted by the neutral line.

      Although the neutral line is earthed at the service entrance and at the
      distribution transformer, the resistance of the neutral wire is USUALLY
      a small fraction of an ohm while the resistance between the two grounds
      may be many ohms or even 10's of ohms. A poorly made or open neutral
      connection can cause significant problems. Since the alternative earth
      connection path typically has much higher resistance, dangerous voltage
      sags and surges can occur across the two 120 volt circuits on the house
      side, especially when temporary high current loads (such as 120 volt
      motors) are started or stopped.

      >
      > One of the reasons that I am asking these questions has to do why what
      > Tesla knew about the earth as an electrical circuit. I realize that the
      > neutral system was not grounded in his day and time like it is today. I
      > heard that he actually inserted a power line into the earth in Colorado.
      > I don't know for sure and there are so many myths and stories that are
      > not true. If it is true and considering that the power companies
      > consider the earth as lossy or conductive, why use a neutral at all? Why
      > not just use the earth itself?

      At low frequencies, the earth is a fair electrical conductor... but not
      nearly as good as metallic conductors. Because of the poorer
      conductivity, it becomes necessary to use arrays of ground rods, large
      areas of buried screens or buried reinforced concrete, sometimes
      augmented by treatment with ionic salts and/or adding moisture to obtain
      a low resistance ground connection. This explains why, when you ground
      each end of a neutral wire and then force a current to flow through the
      parallel combination, virtually all of the current flows through the
      neutral wire while hardly any current flows through the earth path.

      Let's look at some numbers:
      The resistivity of marshy soil (a better-than- average grounding
      environment) is about 10^+4 ohm-cm. Compare this with copper with a
      resistivity of about 1.72 x 10^-6 ohm cm. In other words, copper
      conducts electricity about _5 billion_ times better than marshy soil.
      It's usually more cost effective (as well as being safer and more
      efficient) to use a copper wire return path rather than using the earth
      as a return path. Using a metallic return can also reduce problems
      associated with ground voltage drops and ground potentials. These can
      adversely affect livestock and cause galvanic corrosion problems
      (especially within DC power systems).

      Tesla's wireless power system needed a very solid ground so as to reduce
      system losses in the secondary:topload system. His need to get a "firm
      grip" on the earth was legitimate, since the earth was the other "plate"
      of the capacitor formed between the topload and earth (as in most other
      Tesla Coils).

      >
      > I am sorry to be so bothersome about this question but the fact is that
      > I have yet to hear anyone explain how the neutral really works. If the
      > current all ends up at the substation and is simply grounded there, the
      > earth at the substations would eventually become saturated with charge
      > and cause failures in underground utility pipes and wires?

      Hope this helped a bit. Grounding theory can become quite complex where
      higher currents are involved, such as AC and DC power transmission, RF
      antenna farms, and lightning protection systems.
      >
      > Mark S. Jordan
      > zorbasci@yahoo. com zorbasci@yahoo. com>> > --- On *Tue, 12/29/09, davep@... /<davep@...>/* wrote:> > > From: davep@... <davep@...>> Subject: Re: neutral currents (II) Re: [usa-tesla] Question For The> Group> To: usa-tesla@yahoogrou ps.com> Date: Tuesday, December 29, 2009, 5:59 AM> > > > As apprentice electricians we were told that the whole neutral> wire system> > was for safety.> As a working engineer and technician, i would never put it> that way. (Includes three specific instances of Open Neutral.)> > The GREEN/safety ground is for safety. The WHITE/Neutral is> the current return. Current flows in closed paths from 'source'> to 'load' and then back to source via return. Return needs to> be as large as line to reduce losses. Return can be NOT> connected to 'ground'. In specific cases, for specific> reasons, rare in normal practice return floats. Works fine.> > > Since then the National Electrical Code has been> > tightened up a lot in regards to grounding and bonding. As Spark> > Burmaster once said, "They're trying to draft every stray piece> of metal> > into the American electrical system." The basic assumption is that> > everything is safer when you have multiple paths for electrons.> More or less true. Random bits of metal/conductor, can, as a> result of various kinds of failure float up to random voltages,> which, if high enough, and powered enough present hazard to> ....bags of mostly water... (Us.).> > > So the neutral (white wire) system is one web of paths closely> parallel to> > the hot (black wire) system. The ground (green wire) system is more> > random. This allows some path flexibility when there are electrical> > storms and also when there are inductive phenomena usually> connected with> > heavy motors. All other systems, including plumbing pipes, cable TV,> > phone lines, and cell phone towers have to be bonded into the ground> > system. Hardware requirements for this are strict, in part to> avoid the> > very thing you mentioned about disparities in structure sizes.> Keep in> > mind too that in most electrical panels, the ground wire and> neutral wire> > buses are connected and also usually connected to the outside of the> > panels and any conduit.> cf above. Largely concur.> > > What hasn't been considered includes a number of other areas.> Microwave> > resonance, magnetic fields, space charge, ionic potentials, and storm> > fields are among the things that are not generally considered> within the> > Code, and thus ignored by electricians. But they are all just as> much a> > part of our technical environment, and indeed are in many cases the> > specific manifestations of inefficiency in the grid.> 'microwave resonances'? Irrelevant to power work. (Losses at> microwave are too high for meaningful resonance. I've no idea> what an 'ionic potential' is. 'space charge' exists in a vacuum,> essentially no where else. (at least as such terms are> technically used...)> > > You're right, the current doesn't just disappear. Those electrons are> > still lurking somewhere.> electrons in neutral currents find there way back to their> 'source'. Or another source, makes no difference. Each> source gets as many back as it sends.> > > That's the basis for some of George Wiseman's> > work which had been presented back in 1996 - 98 at Tesla Society> > conferences. Others are looking seriously at what he's done, and are> > trying to duplicate the work.> Its 10 years later....> > > -----Original Message-----> > >> From: Mark Jordan> > >> Subject: Re: neutral currents (II) Re: [usa-tesla] Question For> The Group> > >> I have done a lot of internet research lately> Much of what is on the net is 'questionable' .> > >> and have been unable, so far, to find the info that I am looking> for.> Which is?> > >> I have been told by a local professor that the neutral current> is not> >> induced to return by any action or system at the substations.> This seems incorrect or poorly phrased. What goes out comes> back. Not necessarily the same 'one', but the same 'number'.> There is not a 'specific action or system': its just the> nature of electric currents. They move, when they move> continuously in closed paths.> > >> He also tells me that electrons move in the wires at 2000 ft. per> >> second.> Without checking this maybe close to the 'physical drift of> electrons' speed. The 'effective' velocity is faster, somewhat> slower than the speed of light, varying with details of> conductor arrangement.> > >> The "neutral grid", my term, is the entire neutral system> >> considered as separate from the main lines and the earth.> Inventing ones own language can be useful, also can make> communication difficult.> > >> As far as I can tell, it is just one big system of wires that> >> exist adjacent to the power lines themselves.> The neutral exists to provide return path for the> current/electrons.> (OOOOOOOkay: I'm skipping two phase and three phase. They> would add complications. )> (This is normally covered in a couple of weeks of class time,> with visual aids, weeks more for the polyphase... hard to> do in text....)> > >> With that in mind and correct me if I am wrong, but why would the> >> neutral current go back to the substation or to the generating> >> plant?> Electric current (electrons) flows in closed loops. Circuits.> Out thru the 'hot/line' wire, back thru the neutral/return.> In household work, white is conventionally 'neutral', red or> 'black' the line.> > >> The neutral at the substations appears, to me, to be no different> >> than any other location or structure supplied with electricity.> >> Since current is continuously feeding into> Aha. See Below.> > >> the neutral circuit, it must at some point end up somewhere?> Lets switch to DC for a minute. With things turned on,> Electrons (current) flow into the Positive/'line' connection> on the source and OUT the negative/'return' /neutral. The same> number moving out one, in the other. AC is the same, except> that the electrons move back and forth, as polarity changes.> One half cycle: flow is out the source line terminal, into the> line, down the line, thru the load, back thru the neutral> line to the neutral terminal of the source. When the polarity> flips (we're on AC...) all the flows reverse. (I'll skip> why use AC or DC. Neutral wire can exist (did exist) in both> systems. Same purpose.)> > In a detailed sense, once the neutral current get to 'the first> real ground which is really tied to real ground-ground' 'some'> of the current/electrons slips into ground-ground and flows> thru real ground-ground back to the substation (or other source)> and back thru the substation ground to neutral connection.> > >> It doesn't simply disappear?> Nope. Flows back via neutral/ground parallel path, as above.> > >> Further, if current is flowing into the circuit> Which 'the current'?> Which 'the circuit'?> > >> on the outer extremes of the power grid and another large> >> structure, just down the road and closer to the substation, is> >> sending a greater amount of current into the neutral, wouldn't> >> the potential cause the larger current to flow towards the> >> lesser current?> Guessing a little at the meaning of the question some of the> return/neutral current from the second sub may indeed return> via the ground connection to the first/further, thence to the> source.> > The currents will take paths based on the actual soil> (if ground-ground involved) or wire resistances (if staying> in the neutral conductors) AND WILL split between neutral> and 'ground-ground' paths, depending on details. But. The> same number of current/electrons going out the 'line' will> end up back at the neutral connection of the 'source'.> All this can be measured and verified....> > best> dwp> > > -- *** /\ ************ ********* ********* ********* ********* ******__ _\/_ __ * * * * * * * * *\_\/_/\_\/_/ We specialize in UNIQUE items! Coins shrunk using/\_\/_/\ ultra-strong magnetic fields, Captured Lightning_\/_/\_\/_ (Lichtenberg Figures), & technical Books. Please/_/\_\/_/\_\ come visit us at http://www.captured lightning. com/\ * * * * * * * * **** \/ ************ ********* ********* ********* ********* ******


    • McGalliard, Frederick B
      Microwave resonance? Used an electron beam and microwave resonance to build the klystron back in the early 40s? Or were you thinking of earlier than that?
      Message 2 of 19 , Jan 4, 2010
        Microwave resonance? Used an electron beam and microwave resonance to build the klystron back in the early 40s? Or were you thinking of earlier than that?
        Space charge was, I thought, used to refer to freely moving charges (not confined to a conductor). Voltage is the gradient of the potential field these charges move in. (or the force they experience.)


        From: usa-tesla@yahoogroups.com [mailto:usa-tesla@yahoogroups.com] On Behalf Of Michael Riversong Education
        Sent: Tuesday, December 29, 2009 1:41 PM
        To: usa-tesla@yahoogroups.com
        Subject: Re: neutral currents (II) Re: [usa-tesla] Question For The Group

         

        Thanks for your clarifications, particularly regarding the difference between neutral and ground networks.

        What sort of engineering and technical work are you doing? I suspect we have some divergence in terminology due to differing professional viewpoints. I'm certified in Bau-Biologie, a largely German practice of environmental assessment. We have somewhat differing usages of the terms mentioned, and i'm curious as to the ways you use these terms. Only in relatively recent years have i come to the realization that these terms are largely not considered by the power generation industry.

        Microwave resonance is a relatively recent discovery, and its significance has not yet been determined to the best of my knowledge. It has been observed when microwave transmissions intercept metal constructions such as bedsprings and sculptures. It was first observed in a mountaintop home which was in line of sight to several FM and microwave towers. This house had a free-standing hallway with only one electrical circuit for lights running from one part of the building to another. There happened to be a metal sculpture with a large number of small metal points along the hall. A magnetic field at 60Hz was measured at this point. One of these days i'd like to dig up the original report. This phenomenon has been seen on other occasions.

        Space charge when used in the environmental assessment field denotes an area where voltage can be measured in the air with a simple antenna arrangement feeding into an ordinary AC voltmeter. The numbers in these measurements can only be considered comparative, not absolute. They can often be found behind TV sets, near iron or brass lamps, and emanating from some appliances.

        Ionic potential is often related to storm fields. Essentially the air can carry a positive (electron depletion) or negative (electron excess) charge. Of course this would be thoroughly irrelevant to power engineering, except as it may affect computers and personnel. Certain electronic circuits, especially those with CMOS components, can be affected by positive fields.

        Electromagnetic fields are a whole study in themselves. I'm aware of the controversies concerning these as they emanate from powerlines, and hope we don't get bogged down in those. In general, i have found a few people, up to about 25% of the population, affected by magnetic fields of 1.5 mg or greater. This is more well known in Europe than in America.

        Essentially we lost 5 years after the bankruptcy of the International Tesla Society in 1999. This means that good communication lines among researchers were disrupted during that time. It can take a while to rebuild lines like that. Plus, many of the old leaders are now either dead or disabled. So we are in a process of rebuilding, which is only now beginning to generate good results.

        -----Original Message-----

        From: davep@...

        Sent: Dec 29, 2009 4:59 AM

        To: usa-tesla@yahoogrou ps.com

        Subject: Re: neutral currents (II) Re: [usa-tesla] Question For The Group

        > As
        apprentice electricians we were told that the whole neutral wire system

        > was for safety.

        As a working engineer and technician, i would never put it

        that way. (Includes three specific instances of Open Neutral.)

        The GREEN/safety ground is for safety. The WHITE/Neutral is

        the current return. Current flows in closed paths from 'source'

        to 'load' and then back to source via return. Return needs to

        be as large as line to reduce losses. Return can be NOT

        connected to 'ground'. In specific cases, for specific

        reasons, rare in normal practice return floats. Works fine.

        > What hasn't been considered includes a number of other areas.
        Microwave

        > resonance, magnetic fields, space charge, ionic
        potentials, and storm

        > fields are among the things that are not
        generally considered within the

        > Code, and thus ignored by
        electricians. But they are all just as much a

        > part of our technical
        environment, and indeed are in many cases the

        > specific
        manifestations of inefficiency in the grid.

        'microwave resonances'? Irrelevant to power work. (Losses at

        microwave are too high for meaningful resonance. I've no idea

        what an 'ionic potential' is. 'space charge' exists in a vacuum,

        essentially no where else. (at least as such terms are

        technically used...)

        > You're right, the current
        doesn't just disappear. Those electrons are

        > still lurking
        somewhere.

        electrons in neutral currents find there way back to their

        'source'. Or another source, makes no difference. Each

        source gets as many back as it sends.

        > That's the basis
        for some of George Wiseman's

        > work which had been presented back in
        1996 - 98 at Tesla Society

        > conferences. Others are looking seriously
        at what he's done, and are

        > trying to duplicate the work.

        Its 10 years later....

        -- Michael Riversong
        Tesla Academy
        Cheyenne, Wyoming
        www.teslaacademy. info
        rivedu@earthlink. net

      • teslaedson3@aol.com
        Hi I will not pretend to know about Neutral currents Know my favorite Hero Nikola Tesla(1856-1943) was trying to use UV light to break(?) resistanace through
        Message 3 of 19 , Jan 4, 2010
          Hi I will not pretend to know about Neutral currents Know my favorite"Hero" Nikola Tesla(1856-1943) was trying to use UV light to break(?) resistanace through atomosphere to brodacast his wireless transmitted electric power From his lab Wardenclylffe Long Island in the q900s!(By the way his lab bulidng for now is still standing there many want to preserve it for a Tesla US Museum! Its in danger of being torn down! The place is now called SHOREHAM LONG ISLAND See Google see the Tesla Society www.teslasociety.com for details on saving Wardenclyllfe!) There is an idea(mine to be exact!) to place Seasteading  platforms(see Seasteading Micronations of steel islands in the ocean!) To use Ocean Currents,Solkar and wind power to produce electrcity to be "brioadcast" ala the idea of Tesla or maybe using Microwave power transmission! By the way HAPPY NEW YEAR ALL! Bye Anbdre' (Dr. Edson Andre' Johnson D.D.ULC) 
        • davep@quik.com
          (Pardon if i ramble a bit. Concur with essentially all of Bert Hickman s notes...) ... Wrong set of professionals, perhaps? Its well known, has been for 100
          Message 4 of 19 , Jan 5, 2010
            (Pardon if i ramble a bit. Concur with essentially all
            of Bert Hickman's notes...)

            > Welcome to the real world. This is really strange, but very few
            > professionals have ever been able to explain this.
            Wrong set of professionals, perhaps?
            Its well known, has been for 100 years (ish) in the detail
            power trade. Cities had (have?) 'corrosion committees' a
            bit of time spent with old professional papers will cover it.
            Basic Circuits.

            > That includes master electricians and electrical engineers.
            Some do, some don't. not all 'masters' are masters of
            'all'.

            > Part of the problem is that we are dealing with some phenomena
            > apparently beyond the capabilities of human language or even
            > mathematics.
            Current flow in neutral is strictly conventional, tho a bit
            out of the realm covered by some texts. Further digging
            will find the details.

            > That said, some mathematical explanations have made sense, but
            > only to those who really understand that language.
            Ascribing strange effects to whats really basic, simple,
            circuit behaviour can complicate things.

            > James and Ken Corum come to mind here, and if you can find any of their
            > works you will be on to something.
            I've read some of theirs. seems usable.

            > I've made measurements similar to yours at times. If you are
            > getting too much potential in the neutral line, that's supposed
            > to be repaired. However most electricians don't get around to it
            > unless there is an actual physical problem being manifested.
            been there, done that. basic.

            best
            dwp
          • davep@quik.com
            ... Neutral and ground currents are well understood, as Bert has described, and i attempted to. ... Basic reflections etc. Demonstrated by Hertz in the 1860s.
            Message 5 of 19 , Jan 5, 2010
              > What sort of engineering and technical work are you doing? I suspect we
              > have some divergence in terminology due to differing professional
              > viewpoints. I'm certified in Bau-Biologie, a largely German practice of
              > environmental assessment. We have somewhat differing usages of the terms
              > mentioned, and i'm curious as to the ways you use these terms. Only in
              > relatively recent years have i come to the realization that these terms
              > are largely not considered by the power generation industry.
              Neutral and ground currents are well understood, as Bert
              has described, and i attempted to.

              > Microwave resonance is a relatively recent discovery, and its significance
              > has not yet been determined to the best of my knowledge. It has been
              > observed when microwave transmissions intercept metal constructions such
              > as bedsprings and sculptures. It was first observed in a mountaintop home
              > which was in line of sight to several FM and microwave towers. This house
              > had a free-standing hallway with only one electrical circuit for lights
              > running from one part of the building to another. There happened to be a
              > metal sculpture with a large number of small metal points along the hall.
              > A magnetic field at 60Hz was measured at this point. One of these days
              > i'd like to dig up the original report. This phenomenon has been seen on
              > other occasions.
              Basic reflections etc. Demonstrated by Hertz in the 1860s.
              Takes Really high power levels to get risks. Easy to measure
              low power levels: essentially no documented risks at low
              power levels.

              > Space charge when used in the environmental assessment field denotes an
              > area where voltage can be measured in the air with a simple antenna
              > arrangement feeding into an ordinary AC voltmeter. The numbers in these
              > measurements can only be considered comparative, not absolute. They can
              > often be found behind TV sets, near iron or brass lamps, and emanating
              > from some appliances.
              A more usual term is simply electric field. Try measuring
              at the face of a CRT. Easy to measure, minimal, if any, risks
              at low levels. (tho sundry have made much money selling
              books, etc, based on scaring people...)

              > Ionic potential is often related to storm fields. Essentially the air can
              > carry a positive (electron depletion) or negative (electron excess)
              > charge. Of course this would be thoroughly irrelevant to power
              > engineering, except as it may affect computers and personnel. Certain
              > electronic circuits, especially those with CMOS components, can be
              > affected by positive fields.
              The usual technical term is 'clear air field', or similar.
              Part of the natural environment. Its been around as long as
              the atmosphere.

              > Electromagnetic fields are a whole study in themselves. I'm aware of the
              > controversies concerning these as they emanate from powerlines, and hope
              > we don't get bogged down in those. In general, i have found a few people,
              > up to about 25% of the population, affected by magnetic fields of 1.5 mg
              > or greater. This is more well known in Europe than in America.
              As you say, subject to debate as to effects, if any. I've
              followed, albeit casually, the ramblings for decades: can't
              I've been convinved that there is much to worry about.

              best
              dwp
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