okay so i have 4 hella 500ff lights with 55watt bulbs in them but i only have one wiring harness, can i hook all 4 to one harness and just use a heavy duty relay to power them all?

 

I did this one mine and it seemed to work out fine.

 

alright thanks

 

Yes you can as long as the wiring from the power source to the relay and from the relay to the lights is a minimum of 14 gauge. The remaining harness wiring (control circuit) should be fine as is. You’ll need to adjust the inline fuse to 25 amps for all four.

 

alright thank you

 

neat trick. take the watts, divide by the volts, and you get the amps it will pull. then buy things accordingly.

 

if your formal is correct then ill have 220 watts divided that by 12v and i have 18.333 amps

 

your volts while running will be 14.3 area. but if you want to run them with the truck not running then thats a good way to go. bigger is better in this case

 

they will only be running with the truck is, and if the truck isnt running they would only be running for few seconds

 

A good reason to hook the lights up in pairs is if something happens to one set of lights you still have the other two to get you out !
If you use two relays and properly sized wire you could run two relays off of one switch.

BUT IF you run all four lights on a 30 amp relay make sure to use 12 ga wire and a 30 amp fuse on the power wire from the battery to the relay, pin 30, and then on to the lights.

 

i dont need the lights for offroading, just for looks and when driving at night an no one is around to turn them on and light the road up, and i have a 30 or 40 amp relay and 30 amp fuse and some 12ga laying around so i may try that

 

It will work and the 40 amp relay is better.

Run the 12 ga wire so if you need to leave them on the wire will not over heat.

 

okay thank you

 

This is how I wired mine--one trigger wire, two relays. I still trying to figure out how to wire-up a DPDT(?) switch so that I can switch between either set of 2, or all 4.

 

Not hard to do but you need a diode to put across the feed lines so all four do not come on when you turn on two.

Run separate wires from the two relays to the DPDT sw.

Add a jumper from the two light position to the four light position with a diode in line positioned to restrict the flow from the two back to the four.

Which diode, not sure, try one and see what happens.
Shouldn't need a large value diode, not a lot of current there.
If you get the diode positioned wrong flip the sw or the wires.

Add some indicator lights...

 

Thanks Grev--i might have to try this.