mshields
Senior Member
- Location
- Boston, MA
Where you have 1 generator serving standby and life safety loads; I believe you can come off of a main breaker in the generator to a DP off of which you'd have feeders to multiple LS ATS's (all in a 1 hour rated room - or in Mass in a 2 hour rated room) and also have branch CB's to your standby ATS(s).
I'm now hearing that we can't have standby and life safety being run through the same group mounted distribution panelboard for this purposem per NEC 700.9. In lieu of such a design, you'd have to come off the generator with two separate overcurrent devices, one for standby and one for LS. Or via an individually mounted switchboard such that the breakers were isolated from each other.
This strikes me as correct based on my re-reading 700.9 but I know I've seen group mounted DP's distributing standby and LS power.
Any input?
Thanks,
Mike
I'm now hearing that we can't have standby and life safety being run through the same group mounted distribution panelboard for this purposem per NEC 700.9. In lieu of such a design, you'd have to come off the generator with two separate overcurrent devices, one for standby and one for LS. Or via an individually mounted switchboard such that the breakers were isolated from each other.
This strikes me as correct based on my re-reading 700.9 but I know I've seen group mounted DP's distributing standby and LS power.
Any input?
Thanks,
Mike