Runaway Compressor Control Device?

I have a compressor that I need to leave on 24/7 for purposes of test being run

Twice now I have had the compressor go into a runaway mode where it did no stop running until someone shut it off manually. First time the upper limit switch failed and the second there was a line blow-out over the week-end. Things get very hot, noisy and oily when this happens. And it scares the E36 M3 out of staff if they are around or when they discover it.

I have to think that there is a device that an be bought off the shelf to deal with this. If anyone knows what and where I would welcome the lead.

Pete

Something like this, maybe?

Wire it to a fully rated contactor to kill power to the compressor if the pressure drops below the set point.  

Some further Googling might net a cheaper option.

This problem was brought up elsewhere and the most foolproof solution to me was a single runtime limit switch.  Every time the compressor starts a timer starts counting.  If it goes over a threshold (say 1 hour) a relay or contactor in the system is turned off and must be reset manually. If the system shuts down normally after filling the counter resets. I don't have a link on hand.  

I was thinking about this same problem.  I had a line blow out twice in a week.  It was a plastic line on an auto-drain valve thingie from HF.  Worked great for a couple years, then blew out when I was sanding, then after I spiced it, it blew out again.  Anyway, if that were to happen unattended, like if I forgot to turn the system off, it would be bad.

In reply to GhiaMonster :

That is what I am looking for, I think. Ideally it wont involve designing an electrical enclosure and integrating into the limit switch. I am not going to be allowed to create a device, it needs to come out of a box with a UL rating and into the outlet and then plug the compressor into the device.  If it don't have a UL or something like that on it, it wont be allowed. Or I will have to hire a "certified" individual to install it.

Pete

I have nothing to add except:

I think you need to treat the problems separately..  As there's no way to power up the compressor from completely empty (0 PSI) if you used a range pressure switch, and you don't want it to run for an hour if the tank is already at pressure.

I'd add a second high pressure switch for redundancy, so that's off the shelf.

I'm sure Tork or Intermatic would make an off the shelf electronic timer that runs for 60 minutes or whatever every time it gets power.   I'd just hook that up in line to the pump power, so every time the power gets applied, it can only be applied for up to an hour.  If your compressor recharges the system normally in <10 minutes, then set it for a half hour.   You'll probably need to contact them to find the part number.

It also sounds like you need a pressure relief valve to stop the buildup of dangerous levels of pressure leading to a line blowout.