Light bar wiring doubts

STREETBOB2007

STREETBOB2007

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I've been searching around and I feel like my doubts will be answered here:

ISSUE:
I am looking into adding 4 Hella 500FF series lamps (12V/55W ea) to my 2004 TJ (to be installed to the Light Bar that I just purchased). Each set of light comes with its wiring harness, relay and switch. I already have a Roof Light Switch installed in the center console switch pannel, the switch is rated 12V.

QUESTIONS:

- Is it possible (without burning anything) to install both sets of light (4 lamps total) using 2 relays but to that one switch? (My pet peeve is I don't want to many switches around, plus to keep it as "stock looking" as possible)

- if yes, what do I need? Recommended cabling gage, fuse amperage rating (at the harness/relay)

- Also, thinking of "fuse tapping" from the glove box fuse box (Why? In order to make my life easier and to tap into an "always hot" connection...so that I can turn light light on without having to start my Jeep) - Is it recommended? If not...any suggestion as to where to tap the load from to the switch?

Thanks!

Lights:
HELLA 005750941 500FF Series Driving Lamp Kit,6",clear
https://www.amazon.com/dp/B001TWD5GY/?tag=wranglerorg-20

Switch:
http://rover.ebay.com/rover/1/711-5...0001&campid=5337789113&icep_item=331689366092
 
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- It is definitely possible to install both sets of lights using the two relays and connect them both to a single switch.

- Recommended cable gauging depends on the amperage of each set of bulbs. Them being 55W per bulb at ~13.7 Volts running, leaves you (through V=IR) makes you pull around 9 amps. I would say 12 is ample enough for wiring anything from relay to ground/lights/battery. 14 or 16 gauge from battery to switch to relay.

- I, personally, chose to fuse tape a switched connection, since I don't want random people playing with my Jeep's switches when I'm not around. Fuse tapping is perfectly fine, so long as you do it correctly. If you don't want to fuse tap, then I hear you can direct connect to the battery with an inline fuse.
 
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You can wire both relays to a single switch. You can use the fuse tap to power the switch, so it will give you ignition switched power. The fuse in the fuse tap should be as small as possible (2.5 amps is fine). You can use 18 or 20 AWG from the tap to the switch and from the switch to the relays, and to ground the relay pins.

You should run the main power to the relays from the battery, as four bulbs is a lot of additional current. I would use 12 or 10 AWG wire from the battery to watch relay (one fused run for each) and then 12 or 14 AWG (one run for each bulb) from the relay to each bulb. The ground wire should be the same size. You don't want to connect the outputs of the relays together, as an unbalanced current flow could blow fuses or break relays.
 
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Quick question : What AMP should I use for fuse in the inline fuse from Battery to Relay? 15? 20?

Steel City 06 said:
You can wire both relays to a single switch. You can use the fuse tap to power the switch, so it will give you ignition switched power. The fuse in the fuse tap should be as small as possible (2.5 amps is fine). You can use 18 or 20 AWG from the tap to the switch and from the switch to the relays, and to ground the relay pins.

You should run the main power to the relays from the battery, as four bulbs is a lot of additional current. I would use 12 or 10 AWG wire from the battery to watch relay (one fused run for each) and then 12 or 14 AWG (one run for each bulb) from the relay to each bulb. The ground wire should be the same size. You don't want to connect the outputs of the relays together, as an unbalanced current flow could blow fuses or break relays.
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STREETBOB2007 said:
Quick question : What AMP should I use for fuse in the inline fuse from Battery to Relay? 15? 20?
Click to expand...
Assuming the bulbs are rated at 55 watts at 12 volts, and there are 2 bulbs per relay, you would have roughly 9.2 amps of current draw. Fusing guidance generally recommends 125% of rated load, so a fuse size of at least 11.5 amps is required. The next size commonly available is 15 amps. So a 15 amp fuse will work fine.
 
Gotta ask..... Why use incandescent lights when LEDs use much less current for the same brightness or are much brighter for the same current?
 
Steel City 06 said:
Assuming the bulbs are rated at 55 watts at 12 volts, and there are 2 bulbs per relay, you would have roughly 9.2 amps of current draw. Fusing guidance generally recommends 125% of rated load, so a fuse size of at least 11.5 amps is required. The next size commonly available is 15 amps. So a 15 amp fuse will work fine.
Click to expand...
Thanks!!!
 
TurboTJ said:
Gotta ask..... Why use incandescent lights when LEDs use much less current for the same brightness or are much brighter for the same current?
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I hear you! I went halogen for two main reasons: 1. If the light bulb fails, I just swap the bulb out for a new cheap one...LED's are a bit more complicated in that term and 2. I wanted to keep the "retro" look. Although I know there are Retro looking LEDs out there, but then again reason #1 weights more in my decision.
 
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