"ray lunder" wrote in message
...
The AmplePower people agitate for strict prohibition on this saying it
will smoke the diodes in your alternator. Is this true? What are you
supposed to do? Start the boat with the starting battery, let it run
for 10 minutes, turn the engine off and start it again with the house
batteries and charge them under way? What say all of you?

I had the same concern - I did install a Zap Stop and did switch from
starting battery to house battery (without shutting down motor) after about
1/2 hr of motoring so as to charge the house battery. I did not fry my
alternator, but always had the concern that someone WOULD switch via the OFF
position. I had considered making a removable plate that could be put on the
Guest switch that prevented it from going to "off" but in the end, I
decided to change the set-up and installed a Blue Sea Systems’ Dual
CircuitTM Battery Switch. See:

http://www.bluesea.com/product.asp?Product_id=174086

With this switch, the alternator is always connected to one of the
batteries. It can be set to "combine" to parallel the batteries so
alternator charge gets to both batteries. I believe that this can be done
without shutting down because there is no chance of an open circuit.

However, I also installed a Blue Seas battery combiner with alternator going
to house bank. See:

http://www.bluesea.com/product.asp?P...58&l1=7458&l2=

Although it shows an outboard motor, this is essentially the set-up:

http://www.bluesea.com/Article_detai..._ID=137&id=273

BTW - I have no connection with Blue Seas - Just found these new products
worked well for me.

GBM