ANOTHER ELECTRICAL QUESTION

[TBone]

I have a subpanel with 12 - 120v circuits. The sheathing on the romex wires coming into the panel was cut back so far that I cannot determine which hot wires are paired with which neutral. Without going into a long explanation why, I have a need to know which neutral goes with each hot wire. Anybody got any suggestions on how I can determine that? Thanks.

 

[Diggin It]

Are they behind a wall or in conduit where you can't see them?

 

[Citydude]

I have a subpanel with 12 - 120v circuits. The sheathing on the romex wires coming into the panel was cut back so far that I cannot determine which hot wires are paired with which neutral. Without going into a long explanation why, I have a need to know which neutral goes with each hot wire. Anybody got any suggestions on how I can determine that? Thanks.[/

probably the only solution is to cut out an area above the panel.

 

[Willman]

I have a subpanel with 12 - 120v circuits. The sheathing on the romex wires coming into the panel was cut back so far that I cannot determine which hot wires are paired with which neutral. Without going into a long explanation why, I have a need to know which neutral goes with each hot wire. Anybody got any suggestions on how I can determine that? Thanks.

An electrician that does neat work will have the Sheathing cut back close to the cable connector. He/she will also form and layer the wires neatly in the panel.
So you need to KILL the power to the panel, trace the hot wire from the breaker to where it comes in the panel and then pull out the neutral.

 

[EddieWalker]

I have a subpanel with 12 - 120v circuits. The sheathing on the romex wires coming into the panel was cut back so far that I cannot determine which hot wires are paired with which neutral. Without going into a long explanation why, I have a need to know which neutral goes with each hot wire. Anybody got any suggestions on how I can determine that? Thanks.

I would turn the power off to the panel and disconnect all of the white, neutral wires and all of the ground wires. Then I would do a continuity test from the hot wire to the neutral wires. If one of them goes to a light, the switch will have to be on. If they all go to outlets, then the meter will make a sound when you have continuity.

How To Test For Continuity | Fluke

 

[TBone]

Are they behind a wall or in conduit where you can't see them?

They are in rigid conduit.

 

[TBone]

I would turn the power off to the panel and disconnect all of the white, neutral wires and all of the ground wires. Then I would do a continuity test from the hot wire to the neutral wires. If one of them goes to a light, the switch will have to be on. If they all go to outlets, then the meter will make a sound when you have continuity.

How To Test For Continuity | Fluke

I can see where the light switch trick would work but if the circuit only went to outlets there would have to have a load on them wouldn't they? I don't think you would get continuity between the hot and neutral on an open circuit. I do have a good multi-meter.

 

[repete]

They are in rigid conduit.

If they are in conduit then they should not have the outer wrap of Romex cable but just single strand wire such as THHN. To put romex in conduit I believe would be a code violation.

 

[mwayne]

You can match the current. By that I mean turn off all other loads on the circuit in question. Then put a heat gun or other known load on that circuit and if it pulls 9 amps on the hot, 9 amps will be coming back on the paired neutral.

 

[repete]

I can see where the light switch trick would work but if the circuit only went to outlets there would have to have a load on them wouldn't they? I don't think you would get continuity between the hot and neutral on an open circuit. I do have a good multi-meter.

Just plug in a 110 v heater or something.

 

[Roadworthy]

If I understand the situation (and I may not) there are twelve pairs of wires exiting your sub panel to go "wherever". It would be unusual for these wires to be in NM cable (Romex) inside a conduit. Actually it would be unusual to have rigid conduit at all. Are you sure it's not EMT? Anyhow, all these neutrals probably come from one neutral bus. Why would you even WANT to identify which neutral goes to which circuit?

 

[i7win7]

Don't know why it matters unless replacing wires/upgrading circuits. Sounds like a job for wire tracer.

Wire Tracer Electrical: Amazon.com

 

[kcflhrc]

Romex in conduit, bad idea. Yikes

 

[k0ua]

Without going into a long explanation why, I have a need to know which neutral goes with each hot wire

Please go into the long explanation of why you want to know which of the neutral wires go with which of the hot wires. Because several things you have said don't make any sense. Not the least of which was you state the wires are in rigid conduit and that they are romex. So please sit down and tell us the why.

 

[k0ua]

You could of course find the neutral and hot wire pairs with nothing more than a screwdriver and a lot of time, simply step one : shut off the main. Step two: unhook one of the neutral wires, Step 3 restore main power. Step 4 go around facility and find the outlet or lighting circuit that no longer works. Step 5 shut down main power, and restore the neutral wire. Step 6 flip breakers until that same circuit goes dead. Now you have found the neutral and hot black wire that matches for one circuit. Rinse repeat.

None of this make much sense to me. WHY do you want to know this?

 

[kthompson]

You can match the current. By that I mean turn off all other loads on the circuit in question. Then put a heat gun or other known load on that circuit and if it pulls 9 amps on the hot, 9 amps will be coming back on the paired neutral.

You can buy a clamp style "AMP" meter that will clamp around the wire and do this testing safely and quickly. Follow mwayne's direction.

 

[coobie]

I have a subpanel with 12 - 120v circuits. The sheathing on the romex wires coming into the panel was cut back so far that I cannot determine which hot wires are paired with which neutral. Without going into a long explanation why, I have a need to know which neutral goes with each hot wire. Anybody got any suggestions on how I can determine that? Thanks.

FLUKE meter..

 

[Diggin It]

FLUKE meter..

How will that help him visually identify which white is paired with which black?

 

[Diggin It]

I've run Romex inside thinwall for short distance when I didn't have anything else on hand. But we don't know the situation here. It's probably THHN and we'd know more if the OP told us if what is visible is solid or stranded wire.

 

[kcflhrc]

I've run Romex inside thinwall for short distance when I didn't have anything else on hand. But we don't know the situation here. It's probably THHN and we'd know more if the OP told us if what is visible is solid or stranded wire.

Stranded wire inside an AC Panel? More YIKES