Can you run an air locker from just a pressure tank?

[llamalander]

Curious about the pressure/cfm required to keep an ARB air locker actuated, can this be supplied by a 2.5 gal tank at 120 p.s.i.?
I am guessing the locker does not likely consume air per se, it just uses it to engage and stays that way until the pressure is removed.
If a tank system has no leaks, could it keep the locker engaged indefinitely?
I have an MV-50 I use for tires but don't feel like installing it and plumbing it. When it dies, I'll reconsider replacing it or upgrading.
I'm happy to use it (or the shop compressor) to fill a 2.5 gal. tank that would pressurize the locker, as long as I didn't need to stop and refill the tank every hour to keep the lockers available.
Anyone tried this? I've only read about systems using regulated CO2 tanks, not low pressure (150 p.s.i. max) tanks-

 

[Buliwyf]

Yep.

I've seen racers use Detroit front, Arb rear, with the Arb connected to an air tank. Unsure if it was Co2 or not. But it looked like a Co2 tank.

Small aluminum Scuba tanks look similar. Arb's don't use much air.

 

[TernOverland]

I think the locker only requires 80-90 psi, and mine don't seem to lose air. I've never timed how long it will stay locked on one 2 gal tank, but it's many hours. My compressor almost never cycles once locked.

One thing to consider though. I don't know what happens when you get down to the minimum pressure needed to keep the locker engaged. It could slip into a partially locked condition that could damage the unit. (speculation) If you try the 150psi tank, keep a close eye on it till you know how often it needs to be checked. The volume of air used to lock the unit is tiny. My guess is that it will work well unless you have a leak somewhere.

 

[llamalander]

Thanks! That's a better way to look at the question, how often does a compressor cycle to keep the locker activated-
I think I will plumb the tank to the locker and see what p.s.i. it takes to activate it. Then I can bleed the tank until it disconnects to get an operating range.
I gather ARB lockers will withstand 150 p.s.i. which is where the tank would vent. If I can figure out how long I can maintain working pressure I can gauge my useful window before I need to re-pressurize.

 

[TernOverland]

NO, you definitely want the line going to the ARB solenoids regulated somewhere between 80 -90. Post your run times once you measure them!

 

[Buliwyf]

Scuba 1st stage regulators usually output around 150psi. IIRC, the racers use well over 100psi without any issues. ARB recommends 150psi now. 90 psi was an old spec.

If I'm using just a tank, I want 3000psi of air at least, or go Co2 instead. Such a tank would be no larger than a 2 liter pop bottle.

I believe the company that makes Co2 tanks and regs specifically for this purpose is called "Power Tank".

 

[TernOverland]

Scuba 1st stage regulators usually output around 150psi. IIRC, the racers use well over 100psi without any issues. ARB recommends 150psi now. 90 psi was an old spec.

If I'm using just a tank, I want 3000psi of air at least, or go Co2 instead. Such a tank would be no larger than a 2 liter pop bottle.

I believe the company that makes Co2 tanks and regs specifically for this purpose is called "Power Tank".

Where did you find the 150 psi requirement? The compressors that ARB sells to activate their lockers cut out at 100psi. I have heard that the newest lockers sometimes require more pressure to activate, but the older ones will activate at around 40 psi. I'm not saying that is good place to run though. I think the OP is just looking for a way to keep his lockers locked with his 2.5gal tank, not a full onboard air system.

 

[Buliwyf]

That's straight from ARB. I'm sure they have there reasons for not publishing it.

2.5g's should be OK. But I might crank the pressure up a hair just so that as the tank empties, you're still well within spec.