"Mike" wrote: > I've done the same and recently wiped out (over a 1½ week period) my > smaller battery by flipping a switch that links both the main and back-up > system.
I've been running a 17Ah main battery (later a 21Ah) with a 7Ah backup battery for years. I keep it on a float charger all winter when it's really cold just so the batteries will be warm and ready to go on demand, and I've had no problems at all with the little backup battery. I do have a diode but it's installed the other way from what you describe, I think. My electrical system for the pumps is shown at http://home.hiwaay.net/~langford/electrical/index.html , if that's any help at all. I like to think I have two independent electrical systems, to a large extent... Mark Langford, Huntsville, AL mail: N56ML "at" hiwaay.net website: www.N56ML.com
