NEC 702 Standby Generator Connected to Corridor with NEC 700 Integral Battery Unit

Merry Christmas

strap89

Member
Here's a question I'm trying to get clarity on. Say you have a corridor with an automatic on occupancy sensor controlling the lighting. Some of the fixtures have an integral UL 924 compliant transfer device which transfers to a 90 minute battery source within the fixture. On top of that as an added level of redundancy/performance you put this circuit on a standby generator. The sequence would be outage, followed by the battery operation, then the generator would kick in and take over. So the question is, is it ok for a standby generator to power the emergency lighting if they are equipped with battery packs designed to take the workload if the generator fails? I believe after an outage an occupancy sensor defaults to on for 30 minutes. I've heard differing opinions.
 

ron

Senior Member
Generally, there is no problem having a 702 generator backing up loads that are already powered by locally Article 700 powered items.
However, there are some jurisdictions that require you to backup loads like emergency lighting when you install a 702 generator (optional standby). For example, you can see Section 2702.4 in the NYC Building Code
 

strap89

Member
Generally, there is no problem having a 702 generator backing up loads that are already powered by locally Article 700 powered items.
However, there are some jurisdictions that require you to backup loads like emergency lighting when you install a 702 generator (optional standby). For example, you can see Section 2702.4 in the NYC Building Code

Thanks guys, I guess my concern here is that if part of the building just utilizing battery packs, but the corridors are fully on generator. Are you blurring the lines between life safety and standby, because the corridors would be operating as if it had normal power when the generator kicked on, i.e. occupancy sensors handling the control?
 
Top