The Stovebolt Site Forums The Shop Area The Electrical Bay Fuse size question

I am in the process of replacing the old cloth covered wires in my 47 3600. I removed the old harness pretty much intact. The truck was running a 12v starter and a 12v generator and regulator. It has a 59 235 which I rebuilt. My question is the sizes of fuses that the truck will need now that it has new wiring. I installed a switchable fuse block under the dash so, when you turn on the key the heater, electric wipers, turn signals, fuel gauge, and voltage meter will power up. None of those things had fuses when the truck was built unless they were inline. The light switch and lighting fuses were in tacked but I replaced the 6volt light switch, and upgraded the fuse block to a newer blade style. Does anybody know of a chart that would list the typical size fuses for these systems? I can go by the wattage that the lights would use and come up with the amps for the lighting circuits but a chart would be nice. My truck manual says nothing about the fuses used in this truck even though it would have been 6 volt system, I could have converted to 12v.

A fuse is designed to protect the wire in the circuit, not the end item it's powering. There are some general rules of thumb, but I like to use a 7-10 amp for 18 gauge wires, 12-14 amp for 16 gauge, 20 amp for 14, and 30 amp for 12 gauge. The wire, and the fuse that protects it should be capable of handling about a 50% overload above the current draw of the accessory it's powering. I'm sure one of our electrical gurus will come along shortly and nitpick the above general suggestions. So be it!
Jerry