New headlight harness

[69Ford]

I bought a headlight harness from lmc truck the one that uses two relays to divert the power from going through the switch and directly off the battery. Also I bought a fuse panel that is wired to the battery. The harness did not
have any type of fuses or showed them in the instuctions. I do not want to hook my headlights directly to the battery. My question is what size fuses should I be using basically two circuits one for high beam one for low beam.

[bluef250]

If you have 60 watt H4's I would use 20 amp fuse. Take wattage of lamp divide by 12 and double, then double again. Make sure wire to relay can handle 10 amps. I would use 12 gauge.

http://www.engineeringtoolbox.com/amps- ... d_730.html

60 watt /12 volt (system) = 5 amp per light . 2 lights - 2 (lights) * 5 amps = 10 amps . 10 * 2 = 20 amp. (double for surge.)

[Nitekruizer]

20 amps

[69Ford]

Thank you the harness came all prewired looks like 12 gauge or better wire to the relays. The only thing I do not like is the harness is made overseas and the relays are not the standard bosch type. Might have troubles getting replacements
if they go bad. The good thing is theres two of them one for high beam one for low beam. So if one goes you still have headlights. You may be blinding people but at least you still have lights. Maybe I will change the relay to bosch style
They are pretty cheap. Thanks again everybody. Oh forgot one thing the high and low beams will be on there own circuits two fuses also.

[fbomb100]

. The only thing I do not like is the harness is made overseas .

this why I make my own harness their easy (well once you do one )
your head lights will see what ever your alt is putting out... 13.5 your headlight gets 13.5... 14.6 your headlight gets 14.6.... if getting 12.1 your %$$#@ed