Battery Fuse Sizing - How?

Feb 27, 2004
172
Hunter 335 North East, MD
Going to need some more info on this one... Fuse size, load size, engine starting etc.? Have you continuity tested the fuse?
The fuse was the 300 amp fuse (as in your picture), I have 2 group 31 wet cell batteries with minimal electrics on the boat (sailing instruments and vhf, water pressure and cabin lights), yanmar 3gm30F and no I have not continuity tested the fuses which I will do shortly and get back to you. I have a Charles 50 amp charger from the late 90s and the simple 1-2-off Both switch
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
The fuse was the 300 amp fuse (as in your picture), I have 2 group 31 wet cell batteries with minimal electrics on the boat (sailing instruments and vhf, water pressure and cabin lights), yanmar 3gm30F and no I have not continuity tested the fuses which I will do shortly and get back to you. I have a Charles 50 amp charger from the late 90s and the simple 1-2-off Both switch

You should not have tripped a 300A fuse with a 3GM30 unless something was accidentally shorted... These things are bare bones simple. Drop the fuse over the stud, install the battery lug on top of the fuse, then the washer, lock washer and nut..