neutral/ 120V photo cell

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nizak

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Does the neutral conductor for a 120V photocell have to be the same one that's associated with the load its controlling? Is the neutral at the point of the cell only used to complete the switching function?
 
Considering the same hot is generally used to feed the photocell and the load I do not know of any code compliant way to use a different neutral.
 
nizak said:
Does the neutral conductor for a 120V photocell have to be the same one that's associated with the load its controlling? Is the neutral at the point of the cell only used to complete the switching function?
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I can't think of the situation that would cause this question :)
 
That is the situation I have. Lighting loads are located at the opposite end of the building and all I have is the switch leg at the photocell point.Thought if it was not a violation to do so I would just pull a neutral off the neutral bar in the panel instead of tracing out the unmarked neutrals for the 5 individual loads I'm about to control.Obviously the neutrals are present at the fixture groups because all the lighting worked via single pole switches.
 
nizak said:
That is the situation I have. Lighting loads are located at the opposite end of the building and all I have is the switch leg at the photocell point.Thought if it was not a violation to do so I would just pull a neutral off the neutral bar in the panel instead of tracing out the unmarked neutrals for the 5 individual loads I'm about to control.Obviously the neutrals are present at the fixture groups because all the lighting worked via single pole switches.
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That's what I would do. May not be code compliant though.
What are you feeding the photocells with? You say you have a switch leg present. Is there a hot there too?
 
Had an enclosure with several contactor's that was operated by time clocks. Building sat vacant for years and enclosure took water and damaged everything internally. Loads were negligible on all contactors(3to7 amp max on any given one).At the time of install someone spent a lot of money to operate very little load. Owner would like to have lights operational and at a minimal cost.Photo cells will work fine and cost very little.That's the plan.
 
iwire said:
It would work, it would not be code compliant.
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Just for giggles.... If I come out of my panel with a conductor (in EMT) set a 4 inch box and pull 2 neutrals and the hot to it and go 2 different directions with the hot by splicing it. If I take one neutral and go one way and go the other way with the other neutral that is a code violation?
I'm sure it is but please tell me where that is. ;)
 
Multiwire branch circuit.

Multiwire branch circuit.

If you share a neutral between two or more ungrounded conductors that differ in voltage between them, you have a MWBC. For safety the ungrounded conductors should originate in the same panelboard, if CB, handle ties are required for all ungrounded circuit conductors, and none of the connections in the neutral can be interrupted by devices.

If you "steal" a neutral randomly, then when you turn off one feed breaker, another breaker and load may "backfeed" the neutral and when it is disconnected, the load side of the break may be at line voltage.

Even if the ungrounded conductors are at the same voltage, but fed from different CBs you can have the same effect.

Not a good idea.

This is one of the reasons that 120/240 or 208 neutrals and 277/480 neutrals are to be identified by different markings (colors).
 
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qcroanoke said:
Just for giggles.... If I come out of my panel with a conductor (in EMT) set a 4 inch box and pull 2 neutrals and the hot to it and go 2 different directions with the hot by splicing it. If I take one neutral and go one way and go the other way with the other neutral that is a code violation?
I'm sure it is but please tell me where that is. ;)
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No, multiple neutrals associated with a single ungrounded is not a problem.
 
iwire said:
It certainly is if the additional neutral is also part of another circuit as is the case with the opening poster of this thread.
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And in addition to that, it is a current divider and in turn it becomes an EMF issue if it does not run in close proximity to the other all the way back to the panelboard.

Roger
 
qcroanoke said:
Just for giggles.... If I come out of my panel with a conductor (in EMT) set a 4 inch box and pull 2 neutrals and the hot to it and go 2 different directions with the hot by splicing it. If I take one neutral and go one way and go the other way with the other neutral that is a code violation?
I'm sure it is but please tell me where that is. ;)
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No all the conductors of the same circuit are in the same raceway or cable. Make everything the same except one neutral returns via a different raceway then you have a code violation, even if it is not shared with another circuit in any way.
 
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