Help with building a wire harness

Thanks guys. I'll get the rest of the info on the lights when they get here before I order wire.

 

16 gauge is great for the switches, they don't pull much power and the signal wire for the relay wil hardly pull anything, but use the chart for your power run to the lights.

 

So I found that the lights are 20 watts per light. So if I have 2 lights per circuit it's only 40 watts which means it pulls 3.3333 amps correct? If that's right, then according to the chart on page one I can get away with using 16ga wire I think. Correct me if I am wrong.

 

Yes some switches can be grounded but don't need to be. Alot of 3 prong switches are illuminated which is why I mentioned it.

It can be done with less wire and less complicated using 2 terminal switches. But what is pictured will work.

 

Ok. I understand now. The switches will all be lit.

 

A couple fine points. Your first sketch had each LED pair wired from 10 amp fuses. Be sure you still do that. If you fuse the loads at 10 amps, then you need to run wire appropriate for 10 amps to the loads. Under 6 feet in total length, 16 gauge is fine, longer runs will require heavier wire. If you run only one line from your source to the relays, for the three runs you will need to size the wire for 30 amps (i.e., a minimum of 14 gauge dependent on length). Also, since your relays are SPDT, be sure you use the normal open circuit -- your initial drawing indicated the right pin-outs. Good luck!

 

Correct, but you will want to fuse the wire for 5 amps, if you step up to 10 amp fuse you should use 14 gauge wire because the run will likely be at or over the length limit for 10 amps and 16 gauge wire.

 

Each pair of lights will be going to its own circuit on my blue sea fuse panel. After looking up the wattage for the lights I did decide that I only needed to fuse them with a 5 amp fuse.

 

Update for everybody. I got it all wired and working well. The master switch works perfectly and I didn't have any issues other than getting the wrong diagram with my switches.


Thanks for all the help.

 

Glad you got it working!

 

I have a quick question about the chart. When it says the length of positive feed plus length of negative return. Is that talking about the length of the wire coming from the battery to pin 30 on the relay and the length of the ground wire coming from pin 85 on the relay? I know somebody said that the switch wire wouldn't have to be as big as the others, but what about the load wire pin 87. Should that be the same size as the wire from pin 30 and 85?

 

Pins 85 & 86 only carry a load large enough to keep the relay engaged. Thus they can usually be a smaller gauge wire since their load is lower.

Pins 30 & 87 is the connection that actually powers the device (i.e. the pod lights). These need to be large enough to safely carry the load of the pod lights.

The positive feed (hot wire) would be the connection from the Battery (or fuse box) to pin 30, through the relay, and from pin 87 to the pod light. This would be the total length of wire that consists of the positive feed.

The negative feed (ground) would be from your device (pod light) to wherever you decide to put your ground. Whether that's 6" to the chassis or you choose to run a ground wire 15' from the reverse lights all the way back to your battery it all gets added up since it still carries a load (it may be "zero" volts, but the current still runs back to the battery to complete the circuit).

Don't skimp on the ground, otherwise you'll be in the same position as if you skimped out on your hot wire.

Hope that helps,
-TBC