tony sayer wrote:
I'm thinking that the easiest approach for this is a fuse in the
ground wire to the batteries, it's where the battery isolation
switches are already wired so adding a fuse here would be reasonably
accessible. It looks to me as if a couple of Littelfuse 'mega fuse'
links would do here, they have screw connections but at around 500
amps I guess that's inevitable. Are there any practical alternatives
to the 'mega fuse'?

--
Chris Green
Most fuses and switches intended for AC mains are not suitable for DC
even thought it's a lower voltage.
That's why a lot of automotive stuff gets used on boats.

Concur with that, we used some mains fuses on DC 24 volt supplies they
blew at a lot more then what they were supposed to. Automotive sounds
far more appropriate..

Suppose on of those car hi-fi places might have something suitable
unless anyone else knows different?..

I looked it up. 50A is the biggest blade type fuse.

I started looking at DC motor contactors/trips for low voltage, but got
side tracked.

I am not sure that a fuse in a starter motor is something you want
anyway. Those things can surge to several hundred amps.

There is a reason why they are connected directly to batteries via a
heavy duty solenoid operated contactor.


I would be more inclined to wire them up directly, and have a simple car
blade style fuse panel (any scrappie will have dozens) and make sure the
(upstream) wiring to it is of the highest quality,