candymancangt
DIY
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So im not terrible as electricasl but also not the greatest. I know how to wire up relays and fuses and all that stuff but the wiring sizes for these lights has me in a pickle. The Vehicle is a 1989 Jeep Grand Wagoneer and ive already upgraded its 78A alternator to 150A, with 100A at idle so i have enough Juice. Im adding 6 100w round off-road lights to the Jeep. 4 on the roof and 2 on the bumper.
The light use those H3 fog light bulbs, theyre just 100w. I believe the wire coming from the actual bulb itself is 18AWG its a small maybe 3 inch wire.. The wires that are coming from the housing itself like the ground wire thats screwed to the housing and the wire thats connected to the H3 bulb using a spade connector they are 18AWG as well. Theyre like 7-8 inchs long.
18AWG is very small wire but i know most cars use 18awg for lights, however i know most cars dont supply full 13.8v to lights either using that kind of wiring at the lengths theyre run at
I plan to run a pair of lights together, so 3 pairs for 6 lights, i know 100W is 8.3A, and when paired itll be 16.6A. The amount of wire ill need might be about 10 feet in length to reach the battery from the roof.
My question would be, Would it be ok to entend the existing 18GA wires coming from the lights to another 2-3 feet (so 3-4 feet total 18ga) before i connect them together using a spade terminal onto a 12AWG wire to run the rest of the length to the relay fuse and battery ? 12AWG will carry the 16.6A fine, but would 18GA be ok for a single 100w 8.3 bulb for 2-3 feet ? Or would there be too much power loss.
I also dont want fires or warm wiring or too much voltage drop. Im considering changing the ground and positive wire in the housing of the light to 16AWG and run that for 2-3 feet into the 12AWG. But if i do this, again the H3 bulb wire itself is still 18GA, but thats only like 2-3 inchs long.
I dunno if any of this makes sense
I mean according to this wire calculator Wire Size Calculator - https://www.wirebarn.com/Wire-Calculator-_ep_41.html, it says that 18AWG can handle 8.3A up to 5 feet, at 13.6V if its only 3 feet long. But with total wire length of around 10 feet, that 5 foot length with 18GA the voltage drops to 13.27. If i used 16GA wire it would increase to 13.46 so .19v increase, and 14GA to 13.59v. 14GA seems kind thick to run only 3 feet of wire. But it does increase voltage by .33v over 18GA.
So i dunno, should I get 16GA or 14GA, or would i be ok continuining with the 18GA wire already in the lights if i extend the wiring to 2-3 feet before they splice into the 12AWG wire.
Again the i want the least amount of fire risk, and most amount of voltage i can get to these lights, but also not go too overboard on wire thickness because the H3 bulb itself is only 18GA
The light use those H3 fog light bulbs, theyre just 100w. I believe the wire coming from the actual bulb itself is 18AWG its a small maybe 3 inch wire.. The wires that are coming from the housing itself like the ground wire thats screwed to the housing and the wire thats connected to the H3 bulb using a spade connector they are 18AWG as well. Theyre like 7-8 inchs long.
18AWG is very small wire but i know most cars use 18awg for lights, however i know most cars dont supply full 13.8v to lights either using that kind of wiring at the lengths theyre run at
I plan to run a pair of lights together, so 3 pairs for 6 lights, i know 100W is 8.3A, and when paired itll be 16.6A. The amount of wire ill need might be about 10 feet in length to reach the battery from the roof.
My question would be, Would it be ok to entend the existing 18GA wires coming from the lights to another 2-3 feet (so 3-4 feet total 18ga) before i connect them together using a spade terminal onto a 12AWG wire to run the rest of the length to the relay fuse and battery ? 12AWG will carry the 16.6A fine, but would 18GA be ok for a single 100w 8.3 bulb for 2-3 feet ? Or would there be too much power loss.
I also dont want fires or warm wiring or too much voltage drop. Im considering changing the ground and positive wire in the housing of the light to 16AWG and run that for 2-3 feet into the 12AWG. But if i do this, again the H3 bulb wire itself is still 18GA, but thats only like 2-3 inchs long.
I dunno if any of this makes sense
I mean according to this wire calculator Wire Size Calculator - https://www.wirebarn.com/Wire-Calculator-_ep_41.html, it says that 18AWG can handle 8.3A up to 5 feet, at 13.6V if its only 3 feet long. But with total wire length of around 10 feet, that 5 foot length with 18GA the voltage drops to 13.27. If i used 16GA wire it would increase to 13.46 so .19v increase, and 14GA to 13.59v. 14GA seems kind thick to run only 3 feet of wire. But it does increase voltage by .33v over 18GA.
So i dunno, should I get 16GA or 14GA, or would i be ok continuining with the 18GA wire already in the lights if i extend the wiring to 2-3 feet before they splice into the 12AWG wire.
Again the i want the least amount of fire risk, and most amount of voltage i can get to these lights, but also not go too overboard on wire thickness because the H3 bulb itself is only 18GA
