OBA -> On Board Air Mega Thread & BS

If you want to a different switch, all you need is the power wires and the purple wire.
Wile I did not extend my harness, I did gut all the unnecarry wires and did a custom ch4x4 switch

 

i have a spot that the arb switch would fit in i did some browsing in here and im seeing that the part of the harness to the switches is optional

 

most of it is optional. To make your own, you just need a run that goes from battery to relay to compressor, with a small cutout for the pressure sensor. Then a small wire run that goes from power to switch to the relay to turn on/off.

 

The twin has its own internal relay and pressure switch.

All he needs is to apply +12v to the purple wire to activate the compressor. Once it gets to 150 it’ll shut off.

 

thank you

Im assuming you went to tech? I start there next semester to finish my Mechanical Engineering degree.

 

Indeed I did! 'Congrats, and I'm sure you'll do well.

 

The ARB pressure switches shut off at 100 psi. This eliminates any chance of blowing the seals in the lockers.
The twins do operate at 100% duty cycle which is cool for air tool operation.

 

I would refrain from extending the harness at all. The twins pull 56 amps IIRC. Extending the harness will increase resistance and could possibly melt wires and start an electrical fire.

 

135-150 is the twins cutoff

 

Hmm, not mine, and I’ve had two of them. Do you have ARB lockers?
I have front and rear ARB lockers and anymore than 100 psi, which is where my compressor shuts off, you’ll blow the seals within the locker.
One can modify the compressor if not utilizing ARB lockers though. Out of the box, 100psi shut off is the norm.
Verified by Matt @ ARBUSA.com.

 

I don’t have air lockers and when I add a locker I’m going electric rear lsd front

It’s norm is higher. Mine straight out of the box was going past a 125 safty valve.
When I hook up to air up tires it’s in the 139-149 range.

A screen grab from the arb manual

Very last page: https://www.4wd.com/sku/ARB 4x4 Accessories/standard/CKMTA12.pdf

 

Hmm,
My manual does not reference the pressures you provide. My compressor pressure was verified with a crystal pressure gauge as I didn’t want to blow seals in my lockers. My compressor is actually at 99.1 psi at shutoff. Volume instead of pressure to air up my tires and operate my air tools. Add to that, the seals in my lockers have never blown.
Do you have ARB lockers?

 

ARB docs say otherwise..?
I'm inclined to listen to technical docs not sales people.
https://www.arb.com.au/assets/air-lockers/3-06.pdf

 

Another data point

 

Sandman,
My question is, how new is new?
My lockers and system is 3 years old. I like new tech and all and if there are new upgraded seals available to obtain higher pressures to operate other items, I’m all for it.
Do you have ARB lockers?
Seems nobody wants to answer this.

 

Yes I have arb lockers front and rear, I do not have arb compressors. This is my email from Chase at east coast, I'd consider them professionals and technically inclined enough to provide correct answers. I've also had my lockers for 3 years. If I can dig up my installation manuals I'll check their wording too.

 

My compressor is at least 1-2years old.

No I do not have air lockers. Ya missed my edit ^ when I regear and add a locker in the rear it’s going to be electric. Seen the stories of arb’s leaking.

 

The arb doc I linked is also dated 2016

Run your system like you want, it's your system. Just don't need to scare other people when the documentation clearly reads what psi it (should) operate at. *should because apparently yours doesn't.

 

I could be wrong about this but I think here are actually two pressure regulators in a system that runs an ARB locker. The twin comp has an internal regulator and is the one that cuts off at 135/150 psi. But as you've been pointing out, that is too high for the locker seals.

On my setup there is a 2nd, external regulator along with a small air tank that is for the front locker. IIRC, it shuts off at 90 psi. Here is a pic of the small tank. The pressure regulator solenoid is a small black cube (not pictured) that is mounted on the output side of the air tank, between the tank and the air line to the locker.

 

I run a twin compressor with ARB front and rear. Pressure cutout is 150 and cuts in around 125-135. Been running that setup for about 5 years. No blown seals or issues with anything. Just throwing that out there for those scared shits going to blow up.