Mine is connected to the battery with an inline fuse as well (5 amp fuse) on my 87 K75. I'm trying to use it for a tire compressor but I cant seem to get any power to it. What amp should the fuse be? What else could be the problem?
Thanks in advance!
The fuse is sized to protect the circuit, therefore the circuit dictates the appropriate size fuse. Wire type, size, and length as well as connectors or connection style used as well as any outlet or jack, all determine how much amperage the circuit will carry without failure or more importantly danger from overheating. This is why you commonly see the warning "Risk of Fire - Only replace with XXamp / <style> Fuse"
In other words.. Those plug in air compressors frequently blow the 10amp accessory fuse in automobiles that have a 10A outlet in the dash, now that 15A cigarette lighters have been removed. And while you can easily (although unwisely) swap the 10A fuse for a 15A or even a 20A, you cannot easily (in this case) change the wire, connectors, or other items on the same circuit. So you now run the risk of overheating those components which can lead to failure / FIRE...
Figure out what your "load"(watts) will be on the circuit, then build the circuit to handle that load with a 10 to 25% overhead. (i.e. build a 20A circuit to carry 15A) Also consider the total load you are exposing your battery and alternator to. This is why you upgrade your alternator to run extra lighting, stereos, accessories...etc.
All wire, connectors, switches, and terminals have an amperage rating just like fuses themselves, you just have to select the correct size for the task you are trying to accomplish. While temporarily running an air compressor on an under-sized circuit is probably not going to kill anyone or cause catastrophic failures, it's important to know why its not a good idea and the dynamics behind the danger.
1 amp @ 12V = 12watts
10amp @ 12V = 120 watts
20amp @ 12V = 240 watts
in your house
20amp circuit breaker @ 120V = 2400 watts
