Electrical questions - lights & kill switch

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Aug 1, 2014 | 04:08 PM

rews2

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From: Las Vegas, NV

Electrical questions - lights & kill switch

Hey all.
I wired auxiliary back up lights with power coming off the battery positive side into the cab to a push/pull switch. I have an inline 30amp fuse at the battery, my questio9n is should I also include a relay of some kind? Lights are aftermarket LED driving lights I took off my Magnum.

I want to wire in a hidden kill switch under the dash. What has anyone done for this? Wire it into the ignition switch?

Aug 1, 2014 | 04:47 PM

HIO Silver

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From: NorCal

That's not the right way to wire high current circuits. You need to add separate relays for both the backups and auxiliaries.

Each circuit should basically look like this:

Aug 1, 2014 | 04:56 PM

rews2

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Cool just what I need. On the relay what amp is best?
Sort of expanding the question. Can't remember where I saw it, there was a guy that wired a second fuse block for accessories, lights, stereo and such.
Anyone done something similar? I know a full wiring harness upgrade is the best option it's just not in the budget for now.

Aug 1, 2014 | 05:40 PM

quinletc

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From: Memphis

Kill Switch

I am also curious about the second part of the original post: how would/did you install an ignition kill-switch?

Aug 1, 2014 | 06:11 PM

HIO Silver

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From: NorCal

Quote:

Originally Posted by rews2

I haven't done it yet to my trucks but just last night I was re-wiring a lawn tractor project with auxiliary headlights, LED tail lights, and a horn. I buy electrical components from www.DelCity.net .. relays, pre-made relay pigtails, wire, auxiliary power posts, fuse blocks, terminals (of all kinds!), they have TONS of stuff.

To add a fuse block, the current flow is: Battery --> circuit breaker --> fuse block ..which then distributes power to each protected circuit. Relay sizing depends on what is being powered... Volts x Amps = Watts, or reversed "Power equals Voltage times current (amps)". Solve for amps!

For example, one 55 Watt lamp powered by 12 volts uses 4.6 amps. Then apply a fudge factor of 1.2 or 1.4.. let's say 6.4 amps. Two lights on one circuit is 12.8 amps. A 20-amp relay would be fine but I think the smallest I've encountered recently is a 30-amp and that's okay. Do the math for one 100 Watt lamp.. uh-huh. 8.33 amps times 1.4 is 11.66 amps.. or 23.3 amps for two. Now the 30-amp relay is sized more better.

A kill switch can be installed to interrupt the signal to the "I" wire going to the starter solenoid. A buddy of mine modified the cigarette lighter so that it has to be pushed in to complete the start circuit.

hey.. this is my 9,999ht post! SCARY!

Aug 1, 2014 | 06:27 PM

rews2

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From: Las Vegas, NV

That's a cool site thanks for the link.

Aug 2, 2014 | 10:10 PM

rews2

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From: Las Vegas, NV

Wiring the switch I'm not using a rocker or toggle it's a push/pull sort of looks like a mini headlight switch. Usually I don't sweat how I wire a switch but wiring in this type of circuit will the post or connector be wire specific? The relay wire on a certain post?