Advice on Shop Air Automatic cutoff system

[robstaples]

I had some small leakage in my shop lines and couldn't isolate so I installed a normally closed solenoid valve at the tank and a 12 hour twist mechanical switch. Based on what I'm doing, I twist accordingly. When I'm not using air, my compressor doesn't cycle. When I do, the tank is full, and the lines charge in a hurry. About $ 60.00.

 

[ovrszd]

there are some good idea's here. I am definitely gonna hook up a relay off the lights. It should be no problem really. I was hoping for a similar setup for the air lines. To everyone thou that says just turn the ball valve off and turn the compressor off, REALLY. You are telling me that you never ever forget? I make a habit of turning off everything too, but there are always gonna be times when you might miss it. I appreciate the replies.
Thanks, Dave

Dave if you ever come up with something simple to add to the air line, let me know. I totally trust my relay hooked to the lights and can't think of a better solution. I've never left my lights on overnight. Although, I have walked out of my shop mid-day and didn't turn them off until returning later so even then, I'm not totally protected.

As for timers, etc., I guess they sortta give you protection. If set to go off at midnight and you leave the shop at 6 p.m., and the air line blows at 6:05 p.m., your compressor will only run 5 hours and 45 minutes. Not bad...

 

[ovrszd]

Funny story, a little off subject.

I bought a used 12K drive-on hoist for my shop. Wired it thru a breaker, hot to the switch. The switch was the type that carried the amp load of the motor. So when I push the button to lift the hoist, all the amperage of the motor load was transferred by the switch. To lower the hoist you push and hold a lever.

One day I come in my shop and the hoist is fully lifted. I thought someone was playing a joke on me. Then I noticed there was also a large puddle of hydraulic oil on the floor below the pump assembly. Hmmmm,,, what's going on here???? Checked the system and realized the plastic oil reservoir was melted and drooping off the pump, bottom split open. What the heck????

Lowered the hoist, looked it over, and decided I needed some advice from someone that might know what happened. Called a company that serviced hoists. They told me how the switch was wired and said they no longer build units like that because the switch will eventually fail and short out, causing the hoist to lift. Then the hoist pump will pump against the relief valve until it heats the oil to the point of melting the tank and dumping the oil. Then the pump will run dry until it locks up, which in turn fries the motor.

So,,,,, $500 later I had purchased a new pump unit. This time with a relay used to activate the pump motor and a switch that only has to carry the load of closing the relay.

Oh,,, and yeah,,,, it's now controlled thru the relay that runs my air compressor. Lights off. Hoist off. :thumbsup:

 

[TheGoose]

Uh...set your timer for 6 pm. Problem solved. In fact, you can have almost as many on/off timers as you want. Set it for 6pm and then another at 8 and another at 10 and one more at 12. That way if you're working really late you can simply switch the lever to "on" and then it will kick off once it reaches the off timer.

Dave if you ever come up with something simple to add to the air line, let me know. I totally trust my relay hooked to the lights and can't think of a better solution. I've never left my lights on overnight. Although, I have walked out of my shop mid-day and didn't turn them off until returning later so even then, I'm not totally protected.

As for timers, etc., I guess they sortta give you protection. If set to go off at midnight and you leave the shop at 6 p.m., and the air line blows at 6:05 p.m., your compressor will only run 5 hours and 45 minutes. Not bad...

 

[ovrszd]

Uh...set your timer for 6 pm. Problem solved. In fact, you can have almost as many on/off timers as you want. Set it for 6pm and then another at 8 and another at 10 and one more at 12. That way if you're working really late you can simply switch the lever to "on" and then it will kick off once it reaches the off timer.

Uh... I just don't get it. Why not a simple relay on the shop lights???

 

[TheGoose]

I guess either one will work. I actually thought the light switch relay was a great one, as long as somebody doesn't forget to turn out the lights. Myself I would probably lean to the timer. That way you're guaranteed that it will cut itself off at some point.

Uh... I just don't get it. Why not a simple relay on the shop lights???