Bill Kinney <greatketch@...>
Ian and Judy,
Volvo is right, the engine does not need isolation. BUT, the engine ground system is not isolated to protect the engine.
The C-drive needs to be connected to the Amel bonding system for corrosion control. Unless extra ordinary measures are taken, the engine chassis is going to be electrically connected to the C-drive. Having a full time negative ground on the engine chassis results in full time connection of the 12-Volt Negative connected to the bonding system. Having these two system interconnected is not the way the Amel corrosion control system is designed.
The problem here is if ANY other part of the bonding system has an inadvertent connection to the 12-Volt positive, very severe, and rapid, corrosion can occur. This will not show up on the ground fault lights because those only test for a faults in the 24-Volt system.