On Tue, 16 Nov 2010 07:23:24 +0700, Bruce
wrote:

There are several methods of separating battery banks for use and
connect them for charging. You can use diodes, which take some special
wiring of the regulator to fully charge the batteries, or an automatic
relay system that doesn't.

I had the automatic relay system for a while but for reasons that were
never clear it had a bad habit of sticking in the closed position.
That left the starting battery in parallel with the house bank when it
shouldn't have been. Rather than chase Mr. Kirchhoff around his
endless loops in a complex system, I decided it would be more reliable
to replace the automatic relay with a manual parallell switch, and get
really conscientious about remembering to open it up after shutdown.
So far, so good. Of course I also have to remember to close the
switch after getting underway but a low house bank has a way of
attracting your attention fairly quickly if I forget.