Switch Installation Question

TJim

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Hey everyone!

Kind of "noob" question but...

I am about to finally hard wire my air compressor under my hood. I have researched and studied a lot about the correct wiring.

1584611220589.png


This is the wiring I am going to follow. I am going to use a switch like the below:
1584611317303.png


The only part that I do not really know how to do is the last part. The wire from the dash mounted switch to the Vehicle accessories wire.
Can anyone please explain to me where exactly I have to connect this wire?

I just want to use a simple on/off in dash switch.

Thanks
 
You can tap into a circuit in your glove box fuse panel. The relay coil doesn't need that much amperage to operate the relay.

You could use something like this - a prewired atc mini fuse. They come in any size you need. Whatever circuit you want to use, pop the existing fuse out, then pop in the prewired fuse and wire it to your new switch.

5600PT_medlrg.jpg
 
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You just need some sort of 12v power. Any source in the vehicle will do since all you're doing is triggering a relay. I'd suggest a fuse tap, like the one below, and put it in one of the fuse slots behind the glove box for something that gets power when the Jeep is turned on. Last thing you want to do is accidentally turn the compressor on with the engine off and kill your battery.

fusetap.jpg
 
thanks! I totally understand now.

what kinnd of fuse should I use? how many amps? depends on the switch? or something else?
 
Be sure to use good quality wire and use a 12 ga for the main power and ground. Use appropriate fuse for the compressor. This will help keep the electrical system from heat and load problems. I make it a point to always use a lower gauge wire for all dc systems I build. Keep the fuse rated for the project, not the larger wire. Many (most) will say this isn't needed because the fuse is rated for the thinner wire. The easier the amps can flow the less heat. And less strain on whatever you are wiring in.
 
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so, the switch has 3 pins. the one is the in, the other is the out and the last one is the ground. I am going to to wire the in to the fuse box, but what about the ground?
 
@TJim :

You might find this diagram useful. It was originally published by Currie Enterprises in the 1990's when Currie was marketing 12v compressor systems using Thomas milspec compressors. I found the diagram easy to follow and have referred to it often through the years.

compressor-5.gif



The Currie wiring schematic uses a 12v constant duty solenoid rather than a relay. {Note: it must be a constant duty solenoid, not a starter solenoid.} Both relay and solenoid serve exactly the same function, so use whichever you have available locally as long as it has a sufficient amp rating.


This 2001 article popped up in my Google search for the Currie diagram. It discusses several 12v compressor options available at the time, including a DIY air system that copied the then discontinued Currie system. I had a similar system in my CJ-7, installed in 1997 or 1998.

https://www.4crawler.com/4x4/CheapTricks/OnBoardAir.shtml
 
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@TJim :

You might find this diagram useful. It was originally published by Currie Enterprises in the 1990's when Currie was marketing 12v compressor systems using Thomas milspec compressors. I found the diagram easy to follow and have referred to it often through the years.

View attachment 147174


The Currie wiring schematic uses a 12v constant duty solenoid rather than a relay. {Note: it must be a constant duty solenoid, not a starter solenoid.} Both relay and solenoid serve exactly the same function, so use whichever you have available locally as long as it has a sufficient amp rating.


This 2001 article popped up in my Google search for the Currie diagram. It discusses several 12v compressor options available at the time, including a DIY air system that copied the then discontinued Currie system. I had a similar system in my CJ-7, installed in 1997 or 1998.

https://www.4crawler.com/4x4/CheapTricks/OnBoardAir.shtml
hey ! thats quite useful! according to the toggle switch do you know If I have to ground it and If yes how?
 
Hey everyone!

Kind of "noob" question but...

I am about to finally hard wire my air compressor under my hood. I have researched and studied a lot about the correct wiring.

View attachment 147111

This is the wiring I am going to follow. I am going to use a switch like the below:
View attachment 147112

The only part that I do not really know how to do is the last part. The wire from the dash mounted switch to the Vehicle accessories wire.
Can anyone please explain to me where exactly I have to connect this wire?

I just want to use a simple on/off in dash switch.

Thanks

If you're using a switch that is EXACTLY like the one you posted then yes, it does have a light in the tip of the toggle, and will need to be grounded.
 
Hey Guys! New Question:

Should I wire every switch on a switch panel with its own fuse? Or should I bridge them all together with one fuse?
 
For example, If I use a relay to power the switches which will be power 5 to 7 20-60A Relays?
if all you are running is relays, I'd use 1 fused power source. It saves a lot of wire. I've got a distribution block/ fuse panel under the passenger seat that I run a lot of accessories off of that I don't use a relay to power. If I'm running to a relay and I want switched power from the ignition I steal power from the cigarette lighter that I've converted to a USB power source.
 
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Hey Guys! New Question:

Should I wire every switch on a switch panel with its own fuse? Or should I bridge them all together with one fuse?
That will depend on at least a couple of things that I can think of quickly;
1) if any of them are carrying a load other than to operate a low amp relay coil vs a direct switch higher amp load.
2) if you want isolation to avoid all dropping out if a fuse blows.
 
if all you are running is relays, I'd use 1 fused power source. It saves a lot of wire. I've got a distribution block/ fuse panel under the passenger seat that I run a lot of accessories off of that I don't use a relay to power. If I'm running to a relay and I want switched power from the ignition I steal power from the cigarette lighter that I've converted to a USB power source.

This. Or you can steal power from the fuse block behind the glove box if you have an empty fuse.

Wire all the switch power and ground lines in parallel with a fuse up front.