If you only have one amp on the power wire and that amp is fused at 120A you only need a 125A fuse (closest to 120amp) in the 0awg wire.
A 125A fuse is the safest size fuse for the application, but ANYTHING BETWEEN 125 AMP AND 350 AMP FUSE WILL PROTECT THE WIRE. The important thing to remember here is that fuses have delays in them, and the higher the fuse rating the longer it will take to blow, which could theoretically damage electronics in your car from the "crowbar" effect before the fuse actually blows. Depending on the capacity of your battery it could take several seconds for a 350A fuse to blow when shorted directly to ground!
I guess what I'm trying to say is If you're only worried about only protecting the wire go with a 350A fuse, BUT IF YOU WANT TO PROTECT THE CAR , TOO, DONT GO ANY BIGGER THAN YOU ACTUALLY HAVE TO (125amp). You can always get a larger fuse down the road if needed.
A 125A fuse is the safest size fuse for the application, but ANYTHING BETWEEN 125 AMP AND 350 AMP FUSE WILL PROTECT THE WIRE. The important thing to remember here is that fuses have delays in them, and the higher the fuse rating the longer it will take to blow, which could theoretically damage electronics in your car from the "crowbar" effect before the fuse actually blows. Depending on the capacity of your battery it could take several seconds for a 350A fuse to blow when shorted directly to ground!
I guess what I'm trying to say is If you're only worried about only protecting the wire go with a 350A fuse, BUT IF YOU WANT TO PROTECT THE CAR , TOO, DONT GO ANY BIGGER THAN YOU ACTUALLY HAVE TO (125amp). You can always get a larger fuse down the road if needed.
