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Discussion Starter · #1 ·
So I have a conduit going into a single phase panel. It has 2 red wires, 5 black wires and 5 white wires in it. Nothing is twisted, taped or tied together. Any way of identifying which conductors make the MWBCs?
 

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So I have a conduit going into a single phase panel. It has 2 red wires, 5 black wires and 5 white wires in it. Nothing is twisted, taped or tied together. Any way of identifying which conductors make the MWBCs?
An amp clamp and a pulsing load.
 

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Discussion Starter · #5 ·
I was hoping there might be something I could do in the way of putting a toner on the neutral and maybe picking up the tone on the associated hots? Anything like that?
 

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I see two options.

1) trace them

2) put a clamp meter on them at the JBox and turn em off

You will see a variation on the neutrals readings.
 

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Do all the circuits have some type of load on them?

If so, you can put an amprobe on the neutral and shut off the hots one by one. When you see the neutral load change you know that hot is with that neutral.
 

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If you can shut everything down and Unterm it, you can ohm it out with resistive loads on. Don't try it with cfl lamps in. They won't show up.
 

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Do all the circuits have some type of load on them?

If so, you can put an amprobe on the neutral and shut off the hots one by one. When you see the neutral load change you know that hot is with that neutral.
You beat me. That's funny how we replied the same a minute appart. I am a slow typer.
 

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Do all the circuits have some type of load on them?

If so, you can put an amprobe on the neutral and shut off the hots one by one. When you see the neutral load change you know that hot is with that neutral.
If you can shut everything down and Unterm it, you can ohm it out with resistive loads on. Don't try it with cfl lamps in. They won't show up.
You beat me. That's funny how we replied the same a minute appart. I am a slow typer.
Those are two entirely different methods with different meters.
 

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It would be a hard task. You may be able to assume that the multiwire branch circuit conductors are connected next to each other on opposite phases but the issue may still be which one goes where.

Try taking a reading of amps on the first two conductors then find the neutral that is the difference between the two conductors. Not fail safe but most probably that would be the neutral for those conductors. Thus if one conductor had 10 amps and the other 5 amps then the neutral would have 5 amps.
 

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It would be a hard task. You may be able to assume that the multiwire branch circuit conductors are connected next to each other on opposite phases but the issue may still be which one goes where.

Try taking a reading of amps on the first two conductors then find the neutral that is the difference between the two conductors. Not fail safe but most probably that would be the neutral for those conductors. Thus if one conductor had 10 amps and the other 5 amps then the neutral would have 5 amps.
Yup. And if you shut off the breaker with 5 amps you would see the neutral jump to 10 amps like I was saying in an above post. I think that's a sure fire method, I have done it in malls where there are hundreds of conductors entering into troughs above a row of panels.
 

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Yup. And if you shut off the breaker with 5 amps you would see the neutral jump to 10 amps like I was saying in an above post. I think that's a sure fire method, I have done it in malls where there are hundreds of conductors entering into troughs above a row of panels.
That is an excellent method as long as you are free to shut off circuits. In many cases you may not have that freedom.
 
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Yup. And if you shut off the breaker with 5 amps you would see the neutral jump to 10 amps like I was saying in an above post. I think that's a sure fire method, I have done it in malls where there are hundreds of conductors entering into troughs above a row of panels.
And as I had said previous to you.:whistling2:
 
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