<VV> No Electrics

[Craig Nicol]

I've always installed 60 amp maxi fuses.  You want to avoid nuisance 
failures and common alternators produce 37-55 amps.  A dead-battery 
recharge scenario would blow a 30-amp fuse just on recharge current. You 
also don't want the fuse to blow when your alternator conks out and all 
the power comes from the battery through the fuse.

The idea is to protect the 10 gauge wire, which will definitely be 
protected by a 60 amp fuse for the "short" time required to blow the 
fuse. (Ampacity of wire is a bit slippery based on length, insulation 
temperature tolerance, time of current application).  I've done the math 
but don't have it at my fingertips but I do recall 60 amps was the answer.