Electrical issue

[Highseas]

I have a 2014 freedom 375, always serviced and maintained, I had an electrical issue recently which was a little alarming to me. The issue was one of the fuse holders from the battery charger to one of the batteries caught on fire, luckily it stop at the fuse holder.
The wires are awg 12 and the fuse holder from a replacement fuse holder says 30 amp fuse, there was a 40 amp fuse in the holder and several more for the rest of the batteries. I have changed all fuses to 20 amp, does anyone know what is the max amp for a awg12 wire and has anyone else had this issue. The only item that is used while on shore power is the battery charger, concern Grady white boater

 

[TortugaBob]

20 Amps on 12 Gauge, need 10 Ga for 30 Amp. Maybe a problem with the Battery Charger?

 

[Highseas]

20 Amps on 12 Gauge, need 10 Ga for 30 Amp. Maybe a problem with the Battery Charger?

Do you think that the 12 gauge is sufficient size for the job or should it be up graded
Thanks

 

[SkunkBoat]

To be more correct, the size of the wire needed also depends on the length of the run.
If it was an original "built-in" wire from the charger that had not been extended then it should have been adequate for any case.
There should not have been a 40 amp fuse in a 30 amp holder.

I have seen green corroded fuse holders heat up to the point of melting(burning) plastic without blowing the fuse.
In this case it is not too much current but too much resistance at the fuse holder connection.

 

[TortugaBob]

Correct, didn't get that technical, Voltage drops on long runs, Amps go up. Agreed, design should have been correct, but someone found a problem with fuses popping and upsized the fuse it sounds like. This will cause fires and damage electronics. Maybe he has an aftermarket charger?