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Rick Cantrell
05-11-2009, 07:17 AM
Good morning

I have several questions, and need your advice.

Built in early 80's

There is a panel that is serving 2 120v motors.
Call this panel "B"
Panel "B"'s service is from the loadcenter at the service disconnect.
(30a 240v breaker) (NM 10-2 with ground, (copper))
Panel "B" is wired as follows:
Black wire to 25a breaker for motor "1"
White wire to 25a breaker for motor "2" (No, it was not re-identified)
Bare copper being used as neutral, ground or both

It looks like it was wired this way years ago, with no apparent problems.
But I doesn't seem right to me.

Is it (was it) allowable to have 2 120v loads on a 240 v circuit, and use the bare copper conductor as a neutral?

Was it allowed to have neutral only?
Was it allowed to have ground only?
Or should it have had a seperate neutral and ground?
How/ What do I report?

Thank you for your advice

Jerry Peck
05-11-2009, 07:46 AM
Rick,

No, no, no, no, and (I forgot how many questions you had there) no, and no. ;)

No, it was not allowed to be wired that way.

Rick Cantrell
05-11-2009, 07:59 AM
Jerry
Thank you for you fast responce.
You have more "no"'s than I had questions.:confused:
Should have one of those "No"'s been a yes?
ie: "Or should it have had a seperate neutral and ground?"
If "No" then what?

Jerry Peck
05-11-2009, 08:27 AM
First, the title: multiwire branch circuit ?'s
- No, that is not a "multiwire branch circuit" as a multiwire branch circuit requires a neutral and there is no neutral in that circuit.



There is a panel that is serving 2 120v motors.
Call this panel "B"
Panel "B"'s service is from the loadcenter at the service disconnect.
(30a 240v breaker) (NM 10-2 with ground, (copper))

No, not allowed. A neutral IS REQUIRED to be run to the other panel.


Panel "B" is wired as follows:
Black wire to 25a breaker for motor "1"
White wire to 25a breaker for motor "2" (No, it was not re-identified)

No, that is not allowed. EACH 120 volt motor requires a hot and a neutral, and the neutral is required to be insulated.


Bare copper being used as neutral, ground or both

No, that is not allowed. There is required to be an insulated neutral AND a grounding conductor to those motors.


It looks like it was wired this way years ago, with no apparent problems.

No, it was not allowed back then either.


But I doesn't seem right to me.

You are correct, so I did not say 'no' for that.


Is it (was it) allowable to have 2 120v loads on a 240 v circuit, and use the bare copper conductor as a neutral?

No.


Was it allowed to have neutral only?

No.


Was it allowed to have ground only?

No, "each motor" requires a hot and a neutral, the panel those are fed from also requires a neutral, so the final answer is 'no, it is not correct'.


Or should it have had a seperate neutral and ground?

Yes, see above answers for specifics.


How/ What do I report?

That the panel has no neutral and that each of those 120 volt motors DOES NOT have an insulated neutral AND a grounding conductor.

EVERY 120 volt circuit requires: one insulated "hot" conductor, AND one insulated "grounded"/"neutral" conductor, AND one bare or insulated "grounding" conductor.

EVERY panel which is not service equipment requires an insulated neutral conductor, AND a bare or insulated grounding conductor, AND one or two insulated "hot" conductors (depending on if it supplies 120 volts or 240 volts).

Rick Cantrell
05-11-2009, 09:07 AM
Jerry
As always, you are so helpful. Thank you for taking the time to explane it.