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poppyseed
May 8th, 2013, 21:43
First of yes I searched lol. I really just need someone who knows electrical systems to approve or deny my plan. Im about to wire my roof rack lights on my cherokee, 4 facing forward 2 facing rear. All are 55w lights. I am going to use two lights per relay and switch for a total of 3 relays and 3 switches. Does this wiring diagram look correct? Also what should I use for that solid red square where my large gauge wire from my battery will split into three smaller wires for each relay? Thanks for the help guys!

http://i1359.photobucket.com/albums/q789/Rusty_Etheridge/WiringDiagram_zpsb6a005fb.png

poppyseed
May 8th, 2013, 21:44
and yes my battery and lights will be grounded as well, i just got finger cramps on ms paint :anon:

zachandandy
May 9th, 2013, 06:14
Your wiring diagram looks good, but you may want to go with a larger fuse. 6x55w=330w that's 27.5 amps at 12v. That's a little too close to 30amps for comfort. Throw a 40a fuse in to avoid potential fuse blowing issues.

poppyseed
May 9th, 2013, 10:14
Your wiring diagram looks good, but you may want to go with a larger fuse. 6x55w=330w that's 27.5 amps at 12v. That's a little too close to 30amps for comfort. Throw a 40a fuse in to avoid potential fuse blowing issues.

Thanks for the input I will def do that. I've been told the solid red square should be another fuse block, what size fuses should I use there?

zachandandy
May 9th, 2013, 10:38
A 2nd fuse block isn't necessary, I'd just run the fused hot to each relay. If you wanted to fuse each relay individually, I'd run 3 15 amp fuses.

whitexj98
May 9th, 2013, 10:56
IMO I would run 3 seperate fused wires to each #30. It will make it easier to diag problems and wont kill all lights if there is a short on one of them. I also dont like the idea of one big fuse because it you have a wire get corroded, lights pull excessive amperage or whatever it can heat up enough to burn the wire before ever blowing the big fuse. Also I usually just pigtale off #30 to #85.

poppyseed
May 9th, 2013, 12:44
Also I usually just pigtale off #30 to #85.

As in you connect the power wire to #30 and then a little loop over to #85 as well? that makes the wiring a heck of a lot easier.

xj^REMY
May 9th, 2013, 15:36
Keep the 30A fuse off the battery, with 10 gauge wire, & make the "red square" a fuse block.

http://www.wiringproducts.com/contents/media/6_fuse_panel.jpg

Fuse each 3 circuits with 10A fuse, & use 14 gauge to the lights/switch. 2 x 55w = 110/13.5 = ~8 amps. No need to go with 15A. The fuse in this application is to protect the wire. The lights won't be brighter by using a bigger fuse, & if the wire's capacity is exceeded (14 gauge is good for up to 20A), the fuse won't due it's job, posing a safety risk.

As in you connect the power wire to #30 and then a little loop over to #85 as well? that makes the wiring a heck of a lot easier.

Correct. With this set-up, since you're not tapping off a switched ignition, you'll have use of your fogs with the ignition off. Also, since you're switching the ground, you won't be able to use illuminated switches. Of course, meaning you run the chance of forgetting to turning them off & draining your battery. Just FYI :thumbup:

zachandandy
May 9th, 2013, 15:45
I'd stay with the 15 amp fuses, as the wire is good for it, and if you're running the lights with the ignition off the voltage can easily dip below 12 putting you real close to 10 amps.

WildernessJeep
May 10th, 2013, 19:15
I got tired of running a 40 amp fuse to my roofrack, mostly because I have 4 forward facing 55w lights, but if the compressor is on, I recently winched, or I turn on the side or undercarriage lights, it would blow. Put in an automatic breaker, not a fuse. They are the same size, and when it blows just wait a couple of minutes and turn the lights back on, instead of crawling under the hood to replace the fuse.