Fuses/Circuit Breaker Location

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Oct 8, 2007
Vessel Name
Moon Dance
Vessel Make
1974 34' Marine Trader Sedan
I'm installing a new battery charger in Moon Dance.* On the positive cables from the charger to the batteries, does it really matter at which end of the run the fuse or circuit breaker is located?* I have it in my head that everything needs to be fused as close to the battery as possible, but when I think about it for a minute I wonder why.

The fuse is there to protect the wire from overheating and starting a fire if either the thing it's attached to has a fault or if the wire itself chafes and shorts.*

Here, you've got the battery on one end and the charger on the other.* The charger probably has its own overcurrent*protection in case the wire shorts.* But the battery doesn't.

So put the fuse on the battery end - your head's right!
I prefer to have a CB protect the wire ( unless its huge and T style fuses are required) and have a fuse to protect the various equipment the line feeds.

Type T fuses can be had in quite large amperages , tho not cheap.

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