[mlacouague]

I have an old air compressor run by an old 3HP GE electric motor being powered outside from a 20A breaker in a subpanel. The air compressor is hardwired into the breaker.

I want to install some way of either remotely turning the compressor on and off, mostly so that I dont need to go throw the breaker every morning and evening.

I'm looking for suggestions on how to accomplish this...

 

[joecaption]

220v, 110V ?

 

[AandPDan]

I'd use a mechanical timer.

Assuming 240 volt but you can get 120 volt models.

Like this:

http://www.intermatic.com/en/Products/TimeSwitches/Electromechanical_Switches/24Hour/T100Series/T104.aspx

 

[mlacouague]

I've been looking at the Intermatic T101 and I think it is all I need. But just looking for some reassurance. I would just run the power from the 20A circuit breaker into the timer and from the timer to the compressor?

 

[mlacouague]

I'm sorry, 110V

 

[AandPDan]

Yup,

Power from breaker to timer then to compressor.

Those are very reliable timers. I know some facilities that use them for the parking lot lights and they're well over 20 years old.

 

[mlacouague]

Dan... Is there a reason to go with the 104 as opposed to the 101?

 

[TarheelTerp]

I have an old air compressor
...so that I dont need to go throw the breaker every morning and evening.
I'm looking for suggestions on how to accomplish this...

Occupancy sensor.

 

[AandPDan]

Dan... Is there a reason to go with the 104 as opposed to the 101?

Not if you run it on 120 volt. The 104 is a DPST version.

 

[mlacouague]

Occupancy sensor.

An Occupancy sensor would be great, but I only have 1 spare nuetral running out to the subpanel, so I'm not sure how I would wire it.

 

[mlacouague]

Not if you run it on 120 volt. The 104 is a DPDT version.

Great, thanks for the reassurance guys.

 

[AandPDan]

An Occupancy sensor would be great, but I only have 1 spare nuetral running out to the subpanel, so I'm not sure how I would wire it.

You can use the same neutral that your compressor uses.

 

[mlacouague]

You can use the same neutral that your compressor uses.

I'm gonna definitely show my ignorance here guys, but if someone could point me to an example of that I would need to look for and maybe a real simple explanation for the wiring involved?

 

[AandPDan]

Here's a simple schematic.

It's not difficult.

I don't show grounds.

 

[TarheelTerp]

I'm gonna definitely show my ignorance here guys, but if someone could point me to an example of that I would need to look for and maybe a real simple explanation for the wiring involved?

Wherever the compressor connects now is 120V.
It has the hot and the neutral in it. Set a box there.

Install an occupancy sensor and receptacle. Done.

 

[diystephen]

Will that handle a load like a compressor?

 

[mlacouague]

Here's a simple schematic.

It's not difficult.

I don't show grounds.

Makes sense, only thing is I would need a sensor rated for the compressor, at least 20 amps. A typical wall sensor for lights shouldn't work, correct?

 

[AandPDan]

You need to find a sensor properly rated for the motor load. It isn't like turning on a couple of lights.

The timer is rated for the motor.

 

[TarheelTerp]

Makes sense, only thing is I would need a sensor rated for the compressor, at least 20 amps. A typical wall sensor for lights shouldn't work, correct?

Ve haf vays!

 

[mlacouague]

THANKS GUYS! Seriously appreciate it! Definitely saved me some time and money!