how many lights on one relay

[outinthewoods]

I'm pretty bad at understanding how wiring works....

I've got 4 IPF's for the roof, I'd like to use the 100W bulbs, instead of the 55w.
I have two wiring harnesses that came with them, but one is already wired to the front bumper.

So if it's a 20 or 30 amp relay, can I use just one wiring harness for all four?

400w 30amps equals something ???

[LandCruiserPhil]

Wattage/Voltage=amps

400/12=33.333333333333333333333amps

[GlennA]

I'm pretty bad at understanding how wiring works....

I've got 4 IPF's for the roof, I'd like to use the 100W bulbs, instead of the 55w.
I have two wiring harnesses that came with them, but one is already wired to the front bumper.

So if it's a 20 or 30 amp relay, can I use just one wiring harness for all four?

400w 30amps equals something ???

400W/12V= 33.33 A

I would use two relays. They can be triggered by the same source.

[CanuckMariner]

Gotta love those 24V systems in most 70 series: 400/24=16.67 Amps!

[outinthewoods]

Thanks for the replies!!!

so do I need to wire them completly seperately (2 and 2) or is it possible to wire the relays together?
or what about if all four are wired together, but I only use 2 100w and 2 55w? is it ok to have different draws like that?

[alosix]

4 100 watt lights would be 33.3 amps

Most would probably just use 2 20 or 30 amp relays.

Me, well, I'd probably order up one of these

http://www.delcity.net/store/Normally-Open-12V-Relay/p_791796.a_1

and use it for all 4.

Downside is they 70amp relays won't be @ your local napa.

But.. if you were stuck and needed your lights on a relay isn't all that bad to bypass.

The hard part will be fusing it correctly, but if you dig around the del city site you should be able to find breakers to do such things.