"John W. Bienko" wrote in message
...
Thanks for the expert advice.. now a further clarification..
Having started the engine on #1.. and motoring
out of the harbour.. say 10 minutes.. is it advisable/safe
to switch to #2 on the Master Switch.
Or must one first turn the engine OFF? To protect the alternator.

JWBienko

Your switch should be a "make before break" type to prevent damage to the
alternator. That being said, unless you have a device like a "zap stop"
installed it probably is a good idea to turn the engine off before switching
batteries, just in case.

John Cairns