Lighting Contactor fed from Two Panels

[beanland]

Commercial 120/240V 400A CT metered service feeding two 200A load centers. Two-pole breakers in each panel feed a single 12-contact lighting contactor to feed outdoor lighting. Contactor is controlled by PE cell.

Is there an NEC issue with having branch circuits from two different panels feeding the same lighting contactor?

 

[infinity]

I don't know of any. It not uncommon to have a multi-pole contactor with lighting circuits from both 120 volt and 277 volt sources.

 

[jrohe]

Commercial 120/240V 400A CT metered service feeding two 200A load centers. Two-pole breakers in each panel feed a single 12-contact lighting contactor to feed outdoor lighting. Contactor is controlled by PE cell.

Is there an NEC issue with having branch circuits from two different panels feeding the same lighting contactor?

A little clarification please:

Are you saying the contactor coil is controlled by two circuits - one from two different panelboards? If this is the case, yes, this is an issue.

Or are you saying that the contactor controls circuits that are served by two different panels? If this is the case, no, this is not an issue and is actually quite common.

 

[beanland]

Clarification

Clarification

Contactor is controlled by PE Cell from one 120V circuit.

Multiple 240V circuits from separate panels feed the same contactor.

Thanks for your feedback.

 

[Strife]

As long as it's from same service, I don't see a problem.
Keep in mind however that a transformer is considered a separately derived system and having 277V from a panel and 120V from another panel via a transformer could be considered different services.

Contactor is controlled by PE Cell from one 120V circuit.

Multiple 240V circuits from separate panels feed the same contactor.

Thanks for your feedback.

 

[infinity]

As long as it's from same service, I don't see a problem.
Keep in mind however that a transformer is considered a separately derived system and having 277V from a panel and 120V from another panel via a transformer could be considered different services.

Would that matter? Also some would disagree with the assumption that a transformer makes two different services.

 

[iwire]

As long as it's from same service, I don't see a problem.

I don't see a problem if it is from 18 different services.

Keep in mind however that a transformer is considered a separately derived system

Most times yes.

and having 277V from a panel and 120V from another panel via a transformer could be considered different services.

No, at least not to the NEC.

From Article 100

Service. The conductors and equipment for delivering electric
energy from the serving utility to the wiring system of
the premises served.

 

[ceb58]

Why do we confuse people?

Commercial 120/240V 400A

120 volt and 277 volt sources.

Keep in mind however that a transformer is considered a separately derived system and having 277V from a panel and 120V from another panel via a transformer could be considered different services.

This guy has not said any thing about a three phase system, transformers or 277v

 

[iwire]

Why do we confuse people?

:grin:

It is just one of those inescapable forum dynamics.

 

[infinity]

Why do we confuse people?







This guy has not said any thing about a three phase system, transformers or 277v

The 120 volt and 277 volt circuits were just an example to show that you can have circuits originating from separate panels or services controlled by the same contactor. Sorry if it made the response more confusing.