I need help figuring out what relay i will need for an off road lights install for my 2003 Ford Expedition
Here is what I have ordered so far:
(4) 100 watt General Electric 4537 200,000 candlepower sealed beam bulbs
(4) Grote Par 46 Rubber Housings
(1) N-Fab Light Bar for 2003 Ford Expedition
Here is what I want to use for wiring them:
10 gauge wiring
So with (4) 100 watt bulbs, that's 400 watts divided by a 12 vdc system = 33.3 amps, so I will get a 40 amp fuse to handle between 30-40 amps.
I will also use a 40 amp relay but how do I figure out what ohm rating it should be?
ohm's law resistance calculator says the following:
400 watts (power) divided by 33.3 amps (current) is .36072 ohms. So how do I figure the resistance rating of the relay I need with the number .36072?