Paul, have you thought about the benefits of a manual master cut-off switch?
And Sam obviously Paul shouldn't have a 24 volt system with 5 batteries. My point was that 2 x 8D batteries is insufficient, no matter whether they're wired for 24 or 12 volts. He could still have a single bank system on 24 volts although I realize that is often more difficult to balance because he likely has both 12 and 24 volt loads. The main point of my post was that people need to at least consider having a single bank with a separate genset battery for redundancy. Carrying multiple batteries around just to start the main engine is pretty silly IMHO, particularly so when people think they only have room for 2 batteries in their house bank.