Fuse placements and sizing

PaulRainbow

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I'm not sure of its size but it is thinner. So you're right it will not be protected but we need the amps for the starter motor. I suspect it is wired that way around for precisely that reason.

It's alost unheard of on a boat for the short wire between the alternator and the starter negative to be fused and this has been the case since alternators were invented. Just make sure it is well supported and cannot chafe.
 

PaulRainbow

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I understand what you are saying now, however my Isolator switches are several meters apart. So to achieve that, I would wire the Starter Isolator load as you describe but the domestic load would be from the either main domestic fuse (Mega Fuse 03) or battery terminal itself, probably the later would be easiest.

That will allow you to "jump start" the engine. It would also allow you to isolate a failed engine battery and run the engine from the domestic bank. In the event of a failed domestic battery/bank you would have to disconnect the battery terminal and then close the emergency switch. Nothing wrong with that, just a little less convenient.
 

CapPugwash

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That will allow you to "jump start" the engine. It would also allow you to isolate a failed engine battery and run the engine from the domestic bank. In the event of a failed domestic battery/bank you would have to disconnect the battery terminal and then close the emergency switch. Nothing wrong with that, just a little less convenient.

The simplest way to achieve this is thus I think, although i might use a busbar for the Cyrix CT connection.

1645124323917.png
 

billcole

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Cables running through a storage space like the cockpit locker should ideally be run in conduit or wire armoured. Just saying. Far easier not to have to deal with that kind of issue
Agreed.... I was just trying to think of a plausible scenario for a a cable getting damaged
 
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