Let's say your engine bank has two batteries E1 and E2, and your domestic
bank has D1 and D2. Let's say E1- is permanently connected to E2+, and
likewise D1- to D2+. I'd normally have expected E2- and D2- and the
engine block to be permanently wired together, and any switching to
involve E1+ and D1+ and the starter+ and domestic distribution+ and
the alternator+, while starter- distribution- and alternator- all being
permanently connected to the engine block too. How are your switches
and the link connected exactly?



I've posted a picture with (hopefuuly) an explanation of what I'm tring to
achieve hear
http://www.jassira.com/battery_switches.htm

once again thanks for help