Guys, This is a link to a diagram on how to wire your light bar to a relay, instead of letting it draw power through the ignition switch. It is over complicated. The reason is the light bar already has an off/on switch, so the wires you run are to it, and not to the lights themselves. What is important to understand is what each wire does that comes out of the relay. If you understand that, you can wire it. There are 5 lugs (or wires if you buy one with wires or a plug with wires). You need to understand what each are for, and the diagram tells you that. You only need 4 of these wires, the one labeled 87 is if you want the relay to turn something on. The one labeled 87a is if you want the relay to turn something off. So you only need one of these. Two of the wires go to your battery, one to the positive through a fuse of the same rating as the relay. I use a 30 amp relay, which I am sure someone will say is too big. If you figure that dividing the 70 wall (2 35 watt bulbs) divided by 12 volts, the amps would be 6. Again, someone may take issue with this. The other two wires are the wire that gets made up by the relay to the positive wire from the battery to the thing to be powered. The other wire is where do I get my signal to turn the relay on or off. That wire gets plugged to the positive side of the AUX wire in the headlight.
Read this entire link and you will know more than you ever wanted. I am sure the folks on this post are smarter than me. Also, the diagram on this post is more complicated than the one I can't find at the moment.
VolusiaRiders.com :: View topic - HOW TO: Wiring new accessories through a RELAY