disconnect question

[michaelr]

I have a question. I have a main cabinet with a 480V 3 phase 40 amp service and a 30 amp 115V service coming in. The door has a disconnect to the 480V/40A breaker, and the 115V breaker is inside this enclosure as well. I have a second, smaller enclosure which goes with the system and it is supplied by the 115V from the first enclosure. It is approx. 20 feet away from the main enclosure. Also there is some control wiring going between the two, with some 115V switching logic. Question is, do I need a 115V breaker on the second, smaller enclosure to be code compiant? The 115V/30A is sized for both cabinets. Problems is, if I did put a breaker in the second, when it is opened (for service, etc.) there will still be a potential of 115V logic being switched to this enclosure unless the 115V/30A in the main enclosure is disconnected as well. I was told by a few people that I need a warning label on the second cabinet saying "This cabinet is supplied by more than one power source" to be compliant, but I could not find anything in the NEC stating this. Any ideas?

 

[petersonra]

Re: disconnect question

The NEC requires disconnects in certain cases - such as for a motor. If the panel in question is not one of the cases where a disconnecting means is required, than the NEC does not require you to provide one.

There are other codes that may require a disconnecting means other than the NEC (such as NFPA79 if that were to apply in your case).

LOTO rules require you to identify the sources of energy and where to disconnect those sources of energy. This is not a NEC issue either.

[ May 17, 2005, 10:14 AM: Message edited by: petersonra ]