Emergeny XFR SW location

[sandsnow]

There are two gensets connected to parallelling gear.
There are multiple buildings on the site.
Each bldg has a 1200 amp (w/GFP) feeder from the parallelling gear.
On the load end of the feeder (in each bldg) is a distribution board.
Each dist. board feeds 3 XFR switches. One for emergency and two for optional standby.

The Emergency XFR switch shall be connected directly back to the parallelling gear. My corrx to the designer. 700-9(b)

If you think the system can remain as proposed, then what about the GFP of the feeder? The Code does not require GFP of emergency feeders, however it does not prohibit it. The Code only requires indication of a GFP on emergency feeder.

If you think the system could remain as propoesed, then you would not be thinking the feeder is an emergency feeder, right?
700-26 & 700-7(d)

Could the indication requirement even be complied with if GFP protection was provided?

Thoughts, comments, please?

 

[steve66]

Re: Emergeny XFR SW location

With regard to 700-9(b), I think the 2005 code has clairified that a common feeder can be used from the generator to a distribution panel.

With regard to GFP, nothing says you can't have GFP protection on an emergency source (although it would be a bad design).

A better design would be to terminate the feeder with 2 disconnects both rated at less than 1000A. Then GFP would not be needed. (This is 480V, right? Otherwise you wouldn't need GFP at all).

STeve

 

[sandsnow]

Re: Emergeny XFR SW location

Steve
I found that in the 2005 (the handbook has a diagram)after I posted.

Thanks for the response.

It looks like I'll be accepting it.