Upfitter question for light bar config

[Luchh224]

So, I recently picked up a light bar unused from a buddy of mine, and just want to make sure that my reasoning is sound when getting this thing installed.

1.) The light bar has three wires coming off of it. It will have Positive, Negative, and another wire for the Amber backlight.

2.) assuming that I have JUST those connections with nothing else, would it be safe to assume that if it is a 120W light going to a 12VDC connection (which I think is what’s coming off of the Upfitter hot wire) that would be 10A, so AUX 2 relay would work fine (it’s 15A according to the manual) then I could just go positive to Upfitter hot wire AUX 2, negative to ground, Amber backlight cable to AUX 3.

Is this line of thinking correct with how the truck is wired? Do I need another relay in between all of this? And if so, how will the 2nd relay work? Would two of the relay connections be hooked to the Upfitter hot wire for power? Just a little confused on how to ensure I’m not burning any wires up.

I will also say that the gauge wiring coming off of the light bar is much more robust than the hot wires coming from the Upfitter switches, so that worries me a bit, but the spec sheets says it’s a 120W light and assuming my math is correct above I shouldn’t have an issue with wires getting toasty, correct? Thanks!

 

[pastorwug]

You can always fit a larger 15A fuse in the same circuit. Wires are the same size. Always best to use a relay to the light bar.

 

[Luchh224]

You can always fit a larger 15A fuse in the same circuit. Wires are the same size. Always best to use a relay to the light bar.

Gotcha. I forgot to mention that the light does have a 15A fuse inline on the positive end.

So let’s say I used another relay, here is what I am confused about on that end.

1.) 30 prong will go to power source (I assume battery terminal)
2.) 87 Prong to positive of light bar
3.) 86 Prong to Upfitter AUX 2 hot switch
4.) 85 Prong to ground

Where would would Amber backlight cable be going? Would I just hook straight to AUX3? The gauge of that wire is the same gauge as the Upfitter hot wire.

 

[BAJASVT]

@Luchh224 - You're correct. No relay will be needed; a relay would only be necessary to shorten the length of the larger gauge wire between the light and the switch, but in the case of Raptor with upfitters, it's not necessary if the accessory/light is within the amerage rating of the upfitter switch. Also, 10A based on the 120W would be worst case, it's probably less since typical (not always) automotive amperage ratings are based on 13.8VDC alternator output... so you'd be around 8.7A.

Ground the negative lead from the light, light POS to Aux 2, and backlight POS to Aux 3.

 

[Luchh224]

@Luchh224 - You're correct. No relay will be needed; a relay would only be necessary to shorten the length of the larger gauge wire between the light and the switch, but in the case of Raptor with upfitters, it's not necessary if the accessory/light is within the amerage rating of the upfitter switch. Also, 10A based on the 120W would be worst case, it's probably less since typical (not always) automotive amperage ratings are based on 13.8VDC alternator output... so you'd be around 8.7A.

Ground the negative lead from the light, light POS to Aux 2, and backlight POS to Aux 3.

Alright alright….only thing that does worry me, is that last night I went ahead and did just that, and when I used an extension just to test stuff out the light bar worked, the switches worked, but….wires felt hot. I have done electrical things in the past, but have never done light bar items. Just seemed odd to me that the extension wire was a little warm, or maybe I’m just being paranoid?

 

[BAJASVT]

What light bar is it? If you're under the amperage rating of the switch circuit, you should be fine. Remember, 10A is a respectable load for a single electrical accessory, so it may get warm. Try connecting the + and - leads from the light directly to your battery and see if you notice a difference in the temperature feel of the wire.

 

[Luchh224]

It is a travllerx 30 inch from tractor supply it seems. Looking at the spec sheet it says 120V. I mean yeah you are correct they probably will be prone to some warmth for sure. Just didn’t know if I was buggin out cause it’s my first time doing lighting

What light bar is it? If you're under the amperage rating of the switch circuit, you should be fine. Remember, 10A is a respectable load for a single electrical accessory, so it may get warm. Try connecting the + and - leads from the light directly to your battery and see if you notice a difference in the temperature feel of the wi