120 feed on 208 or 240 volt circuit

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highvolts582

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I A have sign that I am trying to light with 120 the old sign removed had parking lot lights 208 Or 240 unsure feeding through it. The neutral is tied through not connecting to parking lot lights when it gets to the sign they used 120 to hook it up and then 208/240 heads to last parking
Light with no neutral with it for its not needed.

Is it legal to acquire 120 volts in this situation if did this job I would have pulled an extra hot for the 120 volt load. If not I was thinking of mounting a transformer to get the 120 from the
240
 
It is not really clear what you have.
I assume you have 120V and 240V to the first J box where the old 120V rated sign was, and the 240V continued to the parking lot lights. But now you want to have a 120V sign at the parking lot lights but you don't have a neutral???
 
Picture this

Picture this

2 hots and 1 neutral leave the building in a pipe they go to the first light and the light is fed by
The 2 hots. The voltage may be 208 or 240 on those 2 hots one or the other I could not check
The neutral passes through the light from there with the 2 hots. It then goes to the sign. the sign uses the neutral and one hot to feed the sign 120 volts then 2 hots leave the sign to another
Light and is hooked up. Basically Besides the 208/240 provided by the 2 hots they have neutral running out also to give the sign 120 and the hot for the sign jumps off one of the 2 hot
Legs.

Is this allowed? In this situation I would have another hot with that neutral separate from the 2 hots that feed the light. Sign is being removed I need a legal 120 volt feed if what they did is not legal.
 
It is fine as long as the two hots have a common disconnect in the panel. You basically have a multi wire branch circuit with a sharing neutral.

added>>>>2008 Code section 210.4
 
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edward said:
It is fine as long as the two hots have a common disconnect in the panel. You basically have a multi wire branch circuit with a sharing neutral.

added>>>>2008 Code section 210.4
Click to expand...


Really? It just seems weird. That a 2 pole breaker that feed 240 or 208 volt parking lights. And a 120 volt load because they ran the neutral out there also it seems fine It just goes
Against the way I think of feeding things.

Thank you
 
I'm not sure I understand but I think the OP is saying that a 208/240 circuit and a 120 circuit are sharing a neutral wire.
If that's the case IMO it is not legal.
Thanks
Mike
 
mike1061 said:
I'm not sure I understand but I think the OP is saying that a 208/240 circuit and a 120 circuit are sharing a neutral wire.
If that's the case IMO it is not legal.
Thanks
Mike
Click to expand...

No, he is describing a multiwire branch circuit that happens to supply both 120 and 208 or 240 volt loads.

We have exactly the same thing when we supply a subpanel with a feeder. Two or three hots, one neutral carrying unbalanced current from those three hot conductors.
 
As I understand the OP description, this would be compliant with 210.4(C) Exception #2 if a common trip breaker is used. Note that handle ties would not qualify in this case as all the loads are not just line to neutral, rather he has a mixture of line to line and line to neutral load.
 
texie said:
As I understand the OP description, this would be compliant with 210.4(C) Exception #2 if a common trip breaker is used. Note that handle ties would not qualify in this case as all the loads are not just line to neutral, rather he has a mixture of line to line and line to neutral load.
Click to expand...

Correct.
 
kwired said:
No, he is describing a multiwire branch circuit that happens to supply both 120 and 208 or 240 volt loads.

We have exactly the same thing when we supply a subpanel with a feeder. Two or three hots, one neutral carrying unbalanced current from those three hot conductors.
Click to expand...


I see.
Thanks
Mike
 
texie said:
As I understand the OP description, this would be compliant with 210.4(C) Exception #2 if a common trip breaker is used. Note that handle ties would not qualify in this case as all the loads are not just line to neutral, rather he has a mixture of line to line and line to neutral load.
Click to expand...

kwired said:
Correct.
Click to expand...

Why won't a ties handle qualify?

Almost all of the plug in type breakers and even most of the bolt on breakers that are single phase (with only two breakers) are using tie handle, instead of common trip.

Square-d (Homeline) and Murray all have tie handle. Square-d (QO) has a common trip.
 
edward said:
Why won't a ties handle qualify?

Almost all of the plug in type breakers and even most of the bolt on breakers that are single phase (with only two breakers) are using tie handle, instead of common trip.

Square-d (Homeline) and Murray all have tie handle. Square-d (QO) has a common trip.
Click to expand...

Maybe you are thinking that Homeline and other 2 pole breakers look like a handle tie only as opposed to a QO that has only the handle to one side? They are all common trip internally.
IMHO a common trip is required for the OP because the load as described is both line to neutral and line to line and not the same piece of equipment. Take a look at 210.4(C) and Exceptions and see if you agree.
 
QO is possibly the only miniature breaker that only has one handle for multipole breakers. But common trip means if one pole trips they all do. Those with external ties that are marked "common trip" have trip mechanisms that will trip all poles any time one pole sees a trip condition. If you were to remove that factory installed handle tie and subject the breaker to a trip condition on only one pole - the other poles will trip. Field installed handle ties do not ensure tripping of any other poles if one pole trips.
 
mike1061 said:
I'm not sure I understand but I think the OP is saying that a 208/240 circuit and a 120 circuit are sharing a neutral wire.
If that's the case IMO it is not legal.
Thanks
Mike
Click to expand...

The 208 or 240 are not using the neutral. How can the be sharing a neutral??
 
Cavie said:
The 208 or 240 are not using the neutral. How can the be sharing a neutral??
Click to expand...

The 120 volt load and the 240 volt load were all both on same circuit, but that alone is not a code violation. They are sharing one conductor of the circuit - just not the neutral.
 
Cavie said:
The 208 or 240 are not using the neutral. How can the be sharing a neutral??
Click to expand...

There are 240 volt circuits that have a neutral.
It was pointed out how I miss understood the question. And I understand now.
That said it seems wrong to me too, but I see what the more experianced guys are saying.
Thanks
Mike
 
mike1061 said:
There are 240 volt circuits that have a neutral.
It was pointed out how I miss understood the question. And I understand now.
That said it seems wrong to me too, but I see what the more experianced guys are saying.
Thanks
Mike
Click to expand...

Proper way to say this is 120/240 volt circuit.

If you say 240 only, it is assumed there is no 120 volt load associated with the circuit.
 
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