Join Date: Aug 2006
Location: Arlington, VA
Thanked 13 Times in 11 Posts
Rep Power: 12
I agree with most of the above, and generally with the excellent advice you provide. Indeed, the DCP switch is appropriate for many boats.
BTW, the code specifies BOTH a switch and a CPD -- circuit protection device-- i.e., either a fuse or a breaker. Fuses are better IMHO.
One nitpic, though. I don't like the idea of battery combiners. The reasoning is that you could be combining a fully charged battery (say, a start battery) with a nearly depleted and much larger house bank, causing a big inrush of current and all that.
Much better option, IMHO, is one of the several devices designed to maintain a second (e.g., start) battery by sensing charging voltages on the house bank, then providing an appropriate (controlled) charging current for the start battery (unlike the combiners which just connect the two banks together). These are, inter alia, the Xantrex EchoCharge (15A max), the Balmar DuoCharge (30A max), and a new one on the scene, the Magnum Energy Smart Battery Combiner (ME-SBC) which can handle 25A.
The first and third of these are voltage following devices, i.e., they follow whatever charging curve is provided by the main source of charge on the house batteries (alternator, battery charger, solar, wind, etc.). And, they work very well. The ME-SBC is easily programmable for maximum and minimum voltages, etc. The DuoCharge is fully programmable for battery type. There is virtually no voltage loss with these (unlike the older "battery isolators"); they are easy to install, maintenance free, and well worth the investment. My EchoCharge is about 5 years old, and has been in service 24/7 without a hitch. I've installed a bunch of DuoCharge's, too, on client's boats. Haven't seen the new ME-SBC yet, but it looks terrific.
Last edited by btrayfors; 06-29-2009 at 07:22 PM.