1a x 12V x 24hrs = 288 watt-hours on a 48,000 watt-hour battery. My math shows 0.6% of the nominal capacity. And that assumes there is no charging source present.
That being said, I would agree that avoiding it altogether is the wise decision, but there has to be a level at which the tapped load is inconsequential. I'm just curious what that level is! Jason Szumlanski Fafco Solar -----Original Message----- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Hugh Sent: Thursday, September 01, 2011 4:21 PM To: RE-wrenches Subject: Re: [RE-wrenches] unique battery bank design question At 15:57 -0400 1/9/11, Jason Szumlanski wrote: > A 1A @ 12V fan on a 1000aH @48V battery bank can't make any real >difference. Correct me if I am wrong! > Yes that is wrong, because after 4 days you have removed 10% of the nominal capacity or about 20% of the usable capacity. Tapping off batteries is bad practice as universally agreed. One way to mitigate it could be to use separate shunt regulators (diversion load controllers) for each 12-volt portion. This would probably be a healthy feature for 'balancing' any 48 volt battery and would possibly rescue a tapped battery, given enough surplus energy availability (which is usually the key thing for battery health). Just a thought. The snag is the cost. ho hum. -- Hugh Piggott Scoraig http://www.scoraigwind.co.uk _______________________________________________ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org _______________________________________________ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
