HI Bill, Thanks for your thoughts and clarifications on this super simple ( HA) topic.
But can you elaborate on the batteries are a potential massive bomb thing? thanks jay peltz power > On Aug 26, 2015, at 9:19 PM, <billbroo...@sbcglobal.net> > <billbroo...@sbcglobal.net> wrote: > > Ray, > > Do you have a massive battery bank and 3, 8kW inverters inside the house? Is > this in a garage or power shed. If it is a power shed, then 690.12 is not > intended to relate to the power shed. That will be clarified in the 2017 > NEC. > > The area for discussion is what constitutes the length of battery cables. > 690.71 has restrictions on where overcurrent protection needs to be for > circuits longer than 5'. Do people really follow that religiously? This > would be a discussion that really needs to happen with the AHJ. My basic > view is that if I have a 4' run from a battery box to my inverters (even > though one lead may be 10' long), many would call that a 4' run. That is > what is exposed from a fire fighter point of view. Remember the battery is > potentially a massive bomb in a fire, so 48V conductors are the least of a > fire fighter's concern. > > Bottom line is how to make it easy for a firefighter to kill the vast > majority of wires in a building. A backup system simply reenergizes > everything. Cutting off the dc from the array and the ac out of the > inverters solves the problem--keep the battery as close as possible and > don't worry about trying to turn off the battery circuit to the inverter. > > Bill. > > _______________________________________________ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
