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Thread: 60-0-60 Balanced power system

  1. #31
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    Quote Originally Posted by ELA View Post
    In the diagram of the system what does the orange "ground" symbol imply?
    Is that a ground rod or a bond to the house (PE) grounding system?
    A totally separately derived system (without bond to house system) would seem the largest benefit. Don't know about code aspects of that.

    I believe that most smaller commercial isolation transformers that you can purchase, bond secondary neutral, or center tap, to the primary ground (PE) conductor.
    I think its a connection to a GEC, like any other separately derived transformer system.
    Sane people cannot survive being witness to insanity.

  2. #32
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    Quote Originally Posted by tom baker View Post
    When this system came into the NEC as Article 647, the premise was it eliminates noise, as the power is 120 Volts line to line instead of line to neutral.
    Check out http://www.epanorama.net/documents/g...ced_power.html
    Makes sense. Kind of like two 4000 ohm resistors each connected one leg to ground would produce zero current on the EGC because the currents cancel each other out.
    Sane people cannot survive being witness to insanity.

  3. #33
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    Quote Originally Posted by tortuga View Post
    We re-did a recording studio (many years ago) with one of those 60/120 systems, we put different color receptacles within 6 feet of the regular 120V but did not use a special configuration.
    There was a ton of old and new equipment in there, lots of old tube stuff, there was no way a special outlet would have worked.
    The transformer / panel was a listed product, a single unit with a bunch of two pole breakers and dead front GFCI's for each circuit.

    Bottom line is they were extremely pleased with it.

    The graffic should be changed to show a 240V primary as that's what they use on the primary side.

    I have never seen the 6 phase models just the split phase.
    Do anyone have a graffic of the 6 phase?

    By chance was it an Equi=Tech Balanced Power System?

    https://www.equitech.com/productsold/wall-cabinet-systems/

    https://www.equitech.com/


    The theory behind balanced power.

    https://www.equitech.com/the-origin-of-balanced-power/

    .

  4. #34
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    Quote Originally Posted by Jamesco View Post

    Well, if all of the above seems confusing, don’t worry about it. The important thing to understand is that ground wires are dirty because non-linear loads create a condition where zero (ground) is not truly zero. But as originally stated, these are the consequences of a chosen architecture.


    High frequency interference (caused primarily by switching power supplies and other half-current-pulse semiconductor devices) is eliminated by balanced AC architecture in a manner analogous to removing the carrier frequency from an FM broadcast. In the case of balanced power, nulling low frequency harmonic current is in essence “knocking the legs out from under” the high frequency harmonics in the AC system. Everything collapses.


    In audio and video production, the concerns are not much different. How many live mixes have been ruined by background hum? How about nuisance hum bars and something less than black video? How many hours have been wasted by engineers troubleshooting ground loops?

    With the inclusion of balanced power in the 1996 National Electrical Code (Art. 530 Part “G”), the technology is no longer a myth. The advantages of using balanced power are a proven fact. When at one time a technician might have asked, “Do I dare use balanced AC to keep the system clean? The question today is different. The question today is, “Do I dare not use balanced AC?”


    Interesting James.....most bands/sound guys use a
    furman power conditioner, everything goes thru it

    http://www.furmanpower.com/

    many older amps have a ground lift switch, or even a polarity reverse switch.

    and anyone who's done music can probably attest to chasing ground loops about.....

    and so our TN-C-S system comes to mind with all it's inherent objectonable currents literally amplified via non liner loads.

    further, so many sparks from a TN-C system ask why we need the S ?

    Persobally, i've never been able to forward a response in it's defense, and wonder how those TN-C bands fare , and/or TN-C-S equiped bands fare on TN-C turf ?

    ~RJ~

  5. #35
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    Quote Originally Posted by drcampbell View Post
    Hear, here! Balanced three-phase power for everything from locomotives to electric-shaver motors.
    If you corner ground it, don't you still create similar issues/possibilities?
    I live for today, I'm just a day behind.

  6. #36
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    Quote Originally Posted by kwired View Post
    Quote Originally Posted by drcampbell View Post
    Hear, here! Balanced three-phase power for everything from locomotives to electric-shaver motors.
    If you corner ground it, don't you still create similar issues/possibilities?
    I'm pretty sure that would be the case only if there was return current flowing on the ground. But if there's return current flowing on the ground, it isn't a balanced circuit.

  7. #37
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    Quote Originally Posted by drcampbell View Post
    I'm pretty sure that would be the case only if there was return current flowing on the ground. But if there's return current flowing on the ground, it isn't a balanced circuit.
    Problem is when you use a grounded conductor as a circuit conductor, there is always some risk of current flowing back on undesired grounded paths. Three phase wye with no neutral loads - no current on the grounded conductor. Corner grounded delta - usually going to be current on the grounded conductor, otherwise why bother with three phase in the first place? Proper separation of grounded and grounding conductors still helps though.

    Balanced delta (supplying a three phase load) that is corner grounded will have current on the grounded conductor
    I live for today, I'm just a day behind.

  8. #38
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    The secondary would need to be a WYE.

    http://www.equitech.com/products/xfmrs/xfmrs.html


    This is different though.

    http://www.equitech.com/images/nepterm.gif




    .
    Last edited by Jamesco; 04-16-19 at 10:00 PM.

  9. #39
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    Quote Originally Posted by romex jockey View Post
    Well, if all of the above seems confusing, don’t worry about it. The important thing to understand is that ground wires are dirty because non-linear loads create a condition where zero (ground) is not truly zero. But as originally stated, these are the consequences of a chosen architecture.


    High frequency interference (caused primarily by switching power supplies and other half-current-pulse semiconductor devices) is eliminated by balanced AC architecture in a manner analogous to removing the carrier frequency from an FM broadcast. In the case of balanced power, nulling low frequency harmonic current is in essence “knocking the legs out from under” the high frequency harmonics in the AC system. Everything collapses.


    In audio and video production, the concerns are not much different. How many live mixes have been ruined by background hum? How about nuisance hum bars and something less than black video? How many hours have been wasted by engineers troubleshooting ground loops?

    With the inclusion of balanced power in the 1996 National Electrical Code (Art. 530 Part “G”), the technology is no longer a myth. The advantages of using balanced power are a proven fact. When at one time a technician might have asked, “Do I dare use balanced AC to keep the system clean? The question today is different. The question today is, “Do I dare not use balanced AC?”


    Interesting James.....most bands/sound guys use a
    furman power conditioner, everything goes thru it

    http://www.furmanpower.com/

    many older amps have a ground lift switch, or even a polarity reverse switch.

    and anyone who's done music can probably attest to chasing ground loops about.....

    and so our TN-C-S system comes to mind with all it's inherent objectonable currents literally amplified via non liner loads.

    further, so many sparks from a TN-C system ask why we need the S ?

    Persobally, i've never been able to forward a response in it's defense, and wonder how those TN-C bands fare , and/or TN-C-S equiped bands fare on TN-C turf ?

    ~RJ~



    Think of us as a TN-C world in much need of TN-S, but stubborn thanks to (cough POCOs cough) who don't like running more conductors then that which gets the lights lit. And wants the customer paying for the earth electrodes.


    The soviet union and much of far eastern Europe had TN-C right up to the socket outlets until the mid 90s. It seemed like a good idea- I mean why waste money on an extra conductor? That is until a failing connection burnt itself open- putting 220 volts on every metal frame on that circuit. Enough of an issue that it influenced the way splices were made:


    https://youtu.be/KgOKhfVON4Y?t=317


    A "good" set of splices:


    https://youtu.be/udzayPc9mME?t=358
    Sane people cannot survive being witness to insanity.

  10. #40
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    I have a furman monster (currently boxed up), it's a plug in unit. 120v. The line in ground pin of the plug is common to the chassis. The ground on the secondary is floating. to a gfci receptacle.

    I originally mounted it to the rails of the rack with all the all the other equipment installed ... audio hummed and buzzed away.. realized what was going on, Isolated the monster chassis from the rails and silence.

    kept distance between house ground and equipment..

    probably dangerous, but silent...

    (sitting in a box now, it's real silent now)
    " I'm at a crucial part of my painting "...........Monika Danneman

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