Help wiring roof lights in series

[xlr8_87 Advanced Member Find all posts View Profile Close xlr8_87]

Hey guys,

Just wanting some advice regarding wiring my 4 roof lights up. I know everything on running the wires up there, fuses, relays etc but what I was unsure about was how to wire the lights from my power cable up there.
Now to paint the picture for you. I'm running a single, twin core wire upto the roof. It's a 6mm diameter so will be plenty to run the lights. So when I get up there, what's the best way to connect all 4 lights to the one cable? Should I run the 6mm cable alongside all 4 lights, and then have 4 seperate (and smaller gauge) 'offshoots' going to each light? If so, how's the best way to go about offshooting them?
Or, Do I run the power cable straight to the first light (positive) and then T off that and go to the positive of the next light? If so, can you buy 'T' crimp connectors?

And should I do the same for the negative coming down?

here's a picture if what I've said sounds confusing.

[Guest Close Guest]

Re: Help wiring roof lights in series

I would suggest that it would be best to Solder & Heatshrink the connections for weather protection. Use a twin cable and it would be quite neat.

Remember your voltage drop, if running a Negative back to the battery its double the length from normal.

4 x 100Watt? lights will be 32 Amps (give/take) so its a pretty hefty power draw. Maybe look at HID inserts? or lower wattage globes to drop the amperage drawn.
A decent 12volt supplier will have T pieces and different crimps etc, but I would still consider soldering /heatshrink.

Make sure your relay can take the current as well (40 amp)...

[sweetpea Senior Member Find all posts View Profile Close sweetpea]

Re: Help wiring roof lights in series

Hey guys,

Just wanting some advice regarding wiring my 4 roof lights up. I know everything on running the wires up there, fuses, relays etc but what I was unsure about was how to wire the lights from my power cable up there.
Now to paint the picture for you. I'm running a single, twin core wire upto the roof. It's a 6mm diameter so will be plenty to run the lights. So when I get up there, what's the best way to connect all 4 lights to the one cable? Should I run the 6mm cable alongside all 4 lights, and then have 4 seperate (and smaller gauge) 'offshoots' going to each light? If so, how's the best way to go about offshooting them?
Or, Do I run the power cable straight to the first light (positive) and then T off that and go to the positive of the next light? If so, can you buy 'T' crimp connectors?

And should I do the same for the negative coming down?

here's a picture if what I've said sounds confusing.

If you don't have equal length for both positive and eart for all lights they will have different voltages and hence different colours. The light closest to the supply will have the highest voltage and the whitest light. The longer the cable, the more the voltage drop and the more yellow the light.

Take the supply to a point on the bar and then wire all four lights back to that point with equal lengths of the same gauge wire.

You will need to find somewhere to hide the excess cable.

S.

[xlr8_87 Advanced Member Find all posts View Profile Close xlr8_87]

Re: Help wiring roof lights in series

Cheers guys for the input, both helped!

And yeh got myself a 50A relay so should be plenty. Might look at putting in lower wattage globes, not going to bother with HID as that'll be a hassle with all the extra wiring. Will solder and heatshrink all connections apart from going directly into the globes, I'll just crimp and shrink them.

[drivesafe Senior Member Find all posts View Profile Close drivesafe]

Re: Help wiring roof lights in series

Hi Rob, on my last 4x4 I had a quick fit and release bar with 4 roof mounted driving lights and two bumper mounted 130w driving lights.

As posted above, I opted for 55w globes in the roof lights and these give me heaps of good night vision. So much so that I have no bothered fitting bumper mounted lights on my current 4x4.

I just run 4 pairs of 4mm Auto cable split through two fuses and two relays to the roof lights. I have a standard 8 way plug and socket for connecting to the roof lights once they are fitted.

It take about three minutes to fit or remove the lights including connecting the wiring.

I had two IPFs on the bumper and still use the 4 Hella 181s fitted with Phillips Crystal Vision globes, which give really good white light. I do heaps of night driving and the roof bar is now 7 years old and still giving good lighting at night.

The pics below will give you an idea of the night light.

[tinkera Member Find all posts View Profile Close tinkera]

Re: Help wiring roof lights in series

HI Drivesafe Great light setup there great photos as well .Beach takes on a whole new dimension at night i am a bit of a night owl myself.Still cant work out what your driving maybe jeep sport or hyundi.CHEERS TINKERA.

[Snaga Wishing I was lost Find all posts View Profile Close Snaga]

Re: Help wiring roof lights in series

Hi Rob,
The Piranha guy talks about wiring roof lights in the current 4WD action video if you have that. He talks about wiring two pairs rather than all 4 at the same time.

[drivesafe Senior Member Find all posts View Profile Close drivesafe]

Re: Help wiring roof lights in series

Hi Tinkera, it’s my old 03 Range Rover and that’s Fraser Island.

Here’s a daylight shot of my 4x4 roof lights.

I use the same roof lights on my 08 RR but no bumper lights.