Well the construction is beginning for my new switch box and all. I have started with the box construction but have an electricla question.. I want to put a hot wire from the batt to the box in my cab. This way I just have to tie into it to add lighting and radios in the future. I want it to end at a stud fr ease of wiring. As of now it will be powering a GPS, Mastercom switch box, LED visor light, 6 strobes and 2 KC lights. The biggest wire is an 8GA that controls the built in relays on the switch box. The rest are smaller 12 or 14GA wires which will be fused but their power will come from this battery cable. WHat would be a safe GA wire for all this? I am also going to put in a master cut off so as to kill power to the box for work or similar purposes (do not want to get fried). I was thinkin a regular master cut of switch (a big silver on off switch). Will that do or should I consider a relay type set up for it? Thanks.

 

If there is a 8 guage wire in the box for some of the wiring already I would go at least 4 gauge to the box from the battery. Personally I would go with 0 gauge just cause I like to overdue stuff sometimes to play it safe.

 

Pay no attention to the gauge of wire after the distrobution point. What matters is how many amps total can be drawn with EVERYTHING TURNED ON. Each device is fused, obviously. Add up all those fuses. My guesses:

Strobes: 15amp
KC's: 30 amp
LEDs: 5 amps
GPS: 5 amps
Mastercom backlight: 5 amps

60 Amps. 125% rule makes that 75 amps. You can do 10.5ft with 8 gauge wire. Anything bigger than 8 gauge is an incredible waste of time, effort, and money for this application.

 

If I was doing this I might run 4gauge just for future proofing.. ie 2 more 130 watt kc lights or a radio amp..whatever.

I would not go bigger than 4 gauge.. to hard to run etc. I believe in running wire once
so I'd do 4 or 6 gauge whatever you can find a deal on.

 

I did something similar, and I ran 8 GA from the bat inside the cab to my box, fused at the bat with a 100 amp fuse.
Just out of curiosity, how are you constructing this switch box of yours? the one I have has suddenly become too small for my needs, and I need something with a little more room for expansion.

 

Well the switch panel is a regualr switch box. The actual box I am building will house my relays and fuses. It will also house a new Tomar strobe pack and my radios. It is going to be built from plywood and be about 48 x 7 x 15"

 

Oh, I forgot. Fuse that big **** wire within a foot of the battery at 75-80 amps