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Hey guys I have 2 40a relays I was going to use to make my lights brighter. Can I run both high beams on one relay and both lows on one or do I need 4 separate relays. And do you know which color wires going to the lights do what. Thanks
One 30-amp relay for the lows and one 30-amp relays for high beams.
The Math
The formula is: Watts (Power) = Volts times Amperes (Current)
60 Watts = 12 Volts X current....
Solving for current: 60 Watts/12 Volts equals 5 amps.. plus a load factor of 1.5.
Therefore, two 60-watt lamps equals 10 amps times 1.5 equals a 15-amp rating. .. but 20 amp relays aren't common so just go with one 30-amp relay and protect the circuit with a 20-amp fuse.
Get a relay with two terminal outputs, 87 and 87A. Be sure you do not opt for a "change-over" relay because only one output terminal is energized at any one time.
Let's assume you opt for 100-watt high beams:
100 Watts/12 VDC equals 8.33 amps per bulb. That's 16.66 amps total times 1.5 equals 25 amps... that's still good with a 30-amp relay. Protect the circuit with a 25-amp or 30-amp fuse.
You should have used this dual relay plug for a cleaner installation.
Less tacky looking' I have gotten a couple of these but many of the Chinese ones now have smaller ga. wires.
I think the Chinese are now selling wire by measuring the whole wires OD with insulation, not the real wire gauge size which is smaller ID.. Oh that doing business with them
Orich
You should have used this dual relay plug for a cleaner installation.
Less tacky looking' I have gotten a couple of these but many of the Chinese ones now have smaller ga. wires
Orich
I'm going to have to get one of those. Didn't even think about using one. I guess this helped clean it up some for now
Those dual plugs are a good idea, I'll have to remember that for the Mustang, I want to hide everything I can on it. Here is how I did the 70, placed them on the core support beside the battery, all you can see is the top of them. The 3rd one is the fog lights.
