Are Relays Necessary for lighting?

ERAUGrad04

Caught the Bug
So I was all set to build my own relay/fuse box next week thanks to a couple of great write ups here on WAL, however, I got to looking at the current draws and I am second guessing that decision.

For starters, here are the accessories I plan on running and their associated amperage:

* 2 x 6CUBE Inspired Engineering LED lights: 1.38A/each (2.76A total)
* 2 x CUBE Inspired Engineering LED lights: 1.34A/each (2.64A total)
* 1 set of Inspired Engineering LED Rock Lights: >1A
* 1 x Cobra 75 CB: 2A
* 1 x Warn Power Interrupter Solenoid: Negligible power draw

Total draw if everything was selected to ON would be 8.44A.

All switches will be OTRATTW switches rated at 20A @ 12V.

My new thought is to run a 10A fused 10GA wire to the switch panel. Then, I would run individually fused 16GA wires to each accessory via a wire harness down to the passenger side kick panel.

It seems like a fused/relay panel would be overkill unless I'm missing something. I realize I would be running a higher current into the cab of the Jeep, but I feel this can be comfortably mitigated using appropriately rated fuses and wiring for the anticipated load.

Thoughts?
 
I always use relays. It makes changing to different accessories down the road easier and it keeps the load wires out of the living space.
 
running a shit ton of accessories and parking your Jeep for a couple of days=dead battery sooner or later. It also makes tracking down wiring issues and leach drainage nrealy impossible. I would never wire my Jeep or anything without relays

Edit: nearly impossible, not nrealy...lol
 
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Pulled a wire hanging from my bumper to rearrange it, it popped off the connectors, and ZAP! blown fuse in my relay. $2 fix instead of buying new light bars for the bumper. I say yes to relays
 
Pulled a wire hanging from my bumper to rearrange it, it popped off the connectors, and ZAP! blown fuse in my relay. $2 fix instead of buying new light bars for the bumper. I say yes to relays

Just a Fuse would've done the same thing.
 
Just a Fuse would've done the same thing.

The relays add a bit of protection. If you end up using something that has a high current when running using just the switch to complete the circuit then your switch will heat up and it could negatively impact the efficiency of the system and worst case could cause the switch to burn up (depends on amperage). Using a relay while the switch activates the coil on the relay the full Amp of the circuit is passing through the relay, not the switch. In theory the relay could be placed in a safe place like in the engine bay and the switch could be located in the cab.

In short, relays are cheap and reduce the likelihood of a major malfunction in your aftermarket electrical system.
 
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The relays add a bit of protection. If you end up using something that has a high current when running using just the switch to complete the circuit then your switch will heat up and it could negatively impact the efficiency of the system and worst case could cause the switch to burn up (depends on amperage). Using a relay while the switch activates the coil on the relay the full Amp of the circuit is passing through the relay, not the switch. In theory the relay could be placed in a safe place like in the engine bay and the switch could be located in the cab.

In short, relays are cheap and reduce the likelihood of a major malfunction in your aftermarket electrical system.

I know relays are good.. I use several and even carry a spare in my tool bag. They are nice, yes, but not completely necessary on smaller amperage items. Do I recommend them, yes. Can you do things without them, yes- as long as it's a low amperage item.
 
I know relays are good.. I use several and even carry a spare in my tool bag. They are nice, yes, but not completely necessary on smaller amperage items. Do I recommend them, yes. Can you do things without them, yes- as long as it's a low amperage item.

Yup. That's what I was trying to get across, that it's Amperage dependent. Cheers :beer:
 
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