Is you smart charger designed to permanently installed? If so, there should
be no problem having the solar charger and the other battery charger
permanently connected. That is how it is normally done. Since you have the
smart switch isolating the batteries, the typical installation would be for
the solar and 110V charger to be connected to the house battery. The engine
alternator stays on the chassis battery.

Dennis

>From: Loren Busch <starwagen@GMAIL.COM>
>Reply-To: Loren Busch <starwagen@GMAIL.COM>
>To: vanagon@GERRY.VANAGON.COM
>Subject: Aux Battery Charging Alternatives Question for the Electrical
>         Gurus
>Date: Wed, 18 Jul 2007 09:51:51 -0700
>
>Right now I have wiring in place for three ways to charge my aux battery.
>First, and permanently connected, is the alternator when engine is running.
>The next two are wired right now so that only one can be connected at a
>time: Solar charge controller (and solar panel) and an onboard 30 amp
>'smart' charger.
>Question:  What kind of problems, if any, would I encounter if all three
>were connected to the battery at the same time?  Assuming that only one
>would ever be running at any time, would I expect problems such as the
>solar
>controller seeing the voltage from the 110v ac charger and causing damage?
>Or the solar controller seeing the voltage from the alternator and having
>problems?  Or any other combination that should be avoided?  Just to be
>careful I'm now set up so that the solar and the 110v ac charger can't be
>connected to the battery at the same time but the ideal system would be to
>have them permanently wired in.