wiring question

First of all let me start by saying I know a little, but I'm certainly no expert. I have arb's twin compressor, and my question is instead of hooking the main power wires from the compressor to the battery , can I safely hook them to the main hot and ground terminals of the auxiliary fuse block?

 

I wouldn't, those things have a 40 amp fuse and draw quite a bit of juice. The stock fuse block is designed with limitations and I'm sure close to another 40 amps of margin is not built in to the design.

 

The resident ticketed electrician here. I wouldn't, not only because you can't guarantee the ampacity of wire running to the fuse block, but also the limitations of it. Sure it is meant to handle big loads, but only occasionally and for short intervals (IE: ABS system) Continuous load is a whole different story. Why put unnecessary stress on that feeder running to your fuse block when you can tap right off the source? Plus the fact they probably didn't expect and/or make provisions to add loads like that to it. Tap off the battery, I'm sure the compressor has a built in fuse or over-current device anyway.

May I ask; is there a reason you don't like hooking right up to the battery? It's perfectly safe as long as your compressor has a fuse or something similar; which it very likely does. If you want to be even safer, hook the negative up to the frame somewhere instead of the negative terminal. Less chance of any sparking near the battery, as with boosting.

 

What he said and make sure that the compressor has its own fuse or circuit breaker.

 

Thanks for the responses. I was thinking of doing this because I already have the winch hooked to the battery and with the compressor wires there to it's beginning to look kinda messy at the battery terminals, so if you fellows think its a bad idea I won't do it. I really don't wanna burn my truck up.

 

Another electrician chiming in. Get the power from the battery. Id use something like a starter solenoid to turn the compressor on with a switch inside to turn the solenoid on. Also, whichever way you go, put a fuse, say 45 amp, close to the battery. Keep the wire feeding the fuses as short as possible.The fuses protect the wire, not the equipment. I'd also use a number 6 awg wire to feed the compressor.

Saw a buddy years ago wire up a car stereo amp with no fuse. Being in a rush to get it done, ended up cutting into the insulation running the wire. Didn't think anything of the nice spark when connecting it to the battery and almost burnt his car up. Ended up with a nice burn line in the carpet as the short was in the back where the wire went from the cab into the trunk.

 

Ok,thanks. It helps a lot knowing about the selonoid.