Help needed electric kill switch for air compressor

[Bob Engelhardt]

A relay actuated by your lights would work well.

Assuming you're running the compressor on 220v I'm thinking that in the same situation I'd look at running a 110v controlled contactor off the shop lights that then switches the 220v circuit for the compressor. Wired like this it runs when you're in the shop and using stuff and just can't run when the lights are out because it's either night or you're away doing other stuff. ...

Yep - that's the way I have mine set up. The only downside is that when I'm in the garage & want to use air, the cellar lights might not be on.

A solid state relay is an alternative to a contactor - might be cheaper. For 240v, you'd need 2 - one for each leg.

[BCRider]

Assuming you're running the compressor on 220v I'm thinking that in the same situation I'd look at running a 110v controlled contactor off the shop lights that then switches the 220v circuit for the compressor. Wired like this it runs when you're in the shop and using stuff and just can't run when the lights are out because it's either night or you're away doing other stuff.

That's the thing. If you're away on a trip for a few days you don't want it running all day either. Seems like if it can only run when the lights are on then it will only be running when you're in the shop. And if you're in the shop you'll know if there's a failure pretty quickly...

110v contactors to control 220v are pretty common. You'd need to buy the contactor, a box, a few box connectors and wire it in.

[The Artful Bodger]

How about an under-pressure shut off switch, something that will cut off if the compressor if for any reason it is unable to maintain air pressure.

[epicfail48]

Thermal fuse strapped to the compressor head, run to a NO relay the compressor is plugged into? Pump runs for a long time, heats up, trips the fuse, kills the power

Other way i can think of involves a bit more work. Get a microcontroller, current sensor of some breed and a relay. Program the controller so if it reads whatever the operating amp load for your compressor is for longer than 10 minutes, it kills the relay, but the timer can be reset by pressing a button

[Arcane]

A relay actuated by your lights would work well.

[Jerrythepilot]

My wife has been awakened occasionally by my shop compressor kicking on in the middle of the night. A water heater timer is the perfect cure. It powers on after we are awake, and power is off from eight through until morning. Very convenient.
HVAC companies make timer controlled relays that can do what you’re looking for, but the water heater timer may be cheaper and easier to implement.

[chipmaker4130]

Seems like just turning it off at night would be a good solution. You'd probably get used to doing that pretty quickly, eh? For me, a 10min limit would interfere with some things I use it for, but mine can run for an hour without issues.

[true temper]

I want to buy or build a switch for my air compressor to shut it off if a hose breaks in the middle of the night.
I want it to shut off the switch if the compressor runs for say 10 minutes. If it runs more than 10 minutes at a time it will shut down and require a reset to function again.
i have no idea what I need to get this done.