Power to generator accessories & control

[anbm]

NEC 2008 - article 517 requires generator control and accessories (heater, battery charger, etc) to be powerered from life-safety branch.

We had one existing generator installed in 2004 in hospital facilty, now we re-feed it from new emergency parallel gear. The generator has integral load center which sevres all controls and accessories. This load center is currently powered from a normal panel source.

Shoule we need to re-feed this load center from emergency source life-safety branch or just leave it alone. Our problem is we do not have any spare on life-safety branch panel to use. Thanks!

 

[anbm]

To follow up my previous post, I just find out 2008 - NEC 517.32(F) requires generator accessories to be fed from life-safety power branch ...But 517.34(C) also allow generator + other supported pumps, elec. louvers to be fed from non-delay equipment power branch. So, what is the correct choice?


NFPA-99 (2005 version) only requires E.G. accessories to be on equipment power branch. However, the light + outlet at E.G location must be fed from life-safety branch. There is no NFPA-99 2008 version so I can check to verify if they state same as in NEC 2008.


On my opinion, the control or accessories should be fed from life-safety branch and the fuel pumps need to be fed from equipment branch. Any comments?

 

[RUWired]

517.32 Life Safety Branch. no function other than those listed in A through F shall be connected to the life safety branch. The Life
safety branch of the emergency system shall only supply power for the following lighting, receptacles and equipment.

F,generator set accessories. IMO, enclosure heaters, battery chargers, block heaters, are part of the performance of the generator.

Rick

 

[anbm]

But 517.34 also allows generator accessories to be fed from equipment emergency power branch as well as NFPA-99, that's why I am confused.

 

[steve66]

At the generator, you need a light with a battery backup, on the life safety branch. You could have other selected lights at the generator on the life safety branch. You also need at least one receptacle at the generator on the life safety branch.

Other generator equipment including the battery charger and any heaters can be on the equipment branch.

At any rate, you shouldn't leave all this on normal power.