2 Relays on 1 Switch?

[JGBimle]

Iv finished my light bar and will be wiring up my four lights this weekend. I already have two wire so they will pretty much just be relocated from where they were but Il be wiring a second set. After researching and reading some online info most people recommend using two relays for four lights, which I plan to do.

My question is I would like to have one switch to turn on all four lights, so would I have any issues just splicing the wire coming from the second relay that would run to a switch into the wire from the first relay that runs to the already installed switch? As long as the switch has enough power for two relays I should be good right?

 

[xterror04]

yea one switch should be fine

 

[chuckamazuk]

If you are using relays then there should be no lighting load going through the switch. The switch is only operating the relay that sends the heavy load. The easiest way is to take the wire that sends power to the relay from the switch and splice it into two ends, one going to each relay.

See the yellow wires below; they send the power to the relay's to activate them. You will take that load wire from your switch and split it right at the relay's. One end of the split goes into one relay (85) and the second end going into the second relay (85). Hope that helps.

 

[JGBimle]

Wow that diagram is awesome! Thanks guys for the quick responses

 

[Deltaphi216]

it won't let me give you more rep points until i spread some more around. That's an EXCELLENT diagram!

 

[xearth]

It's a little late.... but I've got my 4 hellas running off one switch and no problems with it so far!

 

[2k11pro4x]

chuckamazuk - a genuine question. Is it really necessary to have each relay to power each light? Especially they're only 55W each.
Unless you want independent control for each of those Hella lights on a separate switch? Can you just wire all 4 to 1 relay? I'm sure a 40A relay is more than adequate for 4 x 55W lights.

I ran 4 x 55W lights through 1 40A relay.

220W (4 lights) / 12V = 18.33A. Even using a 30A relay should be just fine.

 

[Fzzt]

Notice that each set of lights Chuck has on a relay are different style or placed lights (backup, driving, fog, flood) so he can turn them on as needed in any combination. Great wiring schematic Chuck! +Rep

 

[JGBimle]

So are you guys saying I could run all four Hella 500s thru one relay?

If so is it as simple as splicing the power wire from the second to lights into the first power wire running to the relay?

 

[Xterraforce]

Notice that each set of lights Chuck has on a relay are different style or placed lights (backup, driving, fog, flood) so he can turn them on as needed in any combination. Great wiring schematic Chuck! +Rep

I also notice that in the description of what light the relays are for, it says 55W x 2 indicating running two lights with each relay.

If you want to run four 55W lights on one 40 amp relay it shouldn't be a problem since the draw would be roughly half of what the relay is rated for. You would need to make sure the wire you use is heavy enough for the load.

 

[chuckamazuk]

I have plenty of overhead in my setup for sure. I wanted to be able to use the same wiring, switches and relays when I upgrade to 100W's in the future.

2K11pro4x is right about being able to run your 4 55W lights on a 40A (even a 30A) relay (see his post above).

You will have one wiring coming off of the relay to feed your lights; I would split the wire and make two ends and then split those to make your 4 power feeds to your 4 lights. The best I can do in ASCII to describe it below:

,---<=====8
---<
'---<=====8

It won't allow spaces; think that lines 1 and 3 are tabbed out to start at the end of the second line.


Thanks for the Rep!