Any problem with this: Switch for compressor

[pitterpat]

I am thinking of adding a switch for the compressor to be the 4th switch in a 4 gang box. The reason I am thinking of putting the compressor outlets on a switch is because the compressor will be in a hard to access place in my garage and I do not want it running all the time. I want to be able to walk into the garage and turn on the switch which will turn on power to the compressor. I don't want the compressor to cycle on and off all the time as I will not be using it every day.
Does anyone see any problem with this?

 

[Charles (in GA)]

Re: Any peoblem with this:Switch for compressor

120v ? 240v ?

What amperage circuit?

Actual HP of the compressor?

Charles

 

[spruce]

Re: Any peoblem with this:Switch for compressor

depends on how much the compressor draws. you can get a 20amp horsepower rated switch.

 

[Zeke]

Re: Any peoblem with this:Switch for compressor

depends on how much the compressor draws. you can get a 20amp horsepower rated switch.

That's what I use on the typical 120v 30 gallon compressor often labeled these days as "5" HP.

 

[theoldwizard1]

Re: Any peoblem with this:Switch for compressor

You need a switch that is rated for the HP of the compressor.

 

[pitterpat]

Re: Any peoblem with this:Switch for compressor

120v ? 240v ?

What amperage circuit?

Actual HP of the compressor?

Charles

15 amp, 240 circuit (funny plug with one blade sideways) 20 amp

HP...don't know too cold to go look at it.

 

[pitterpat]

Re: Any peoblem with this:Switch for compressor

You need a switch that is rated for the HP of the compressor.

Like a 20 amp switch?

 

[larry_g]

Re: Any peoblem with this:Switch for compressor

You can also add a motor starter relay in the circuit that will allow you to run a low amperage circuit to the switch. You would install the switch in the control wire between the pressure switch and the relay.

lg
no neat sig line

 

[tdkkart]

Re: Any peoblem with this:Switch for compressor

You can also add a motor starter relay in the circuit that will allow you to run a low amperage circuit to the switch. You would install the switch in the control wire between the pressure switch and the relay.

This is pretty much what I did with mine, I've got a contactor with a 120V coil.
Ran a wire off one of my rows of lights to control the coil via the pressure switch. Power from the lights, to the pressure switch which then feeds the pull-in coil on the contactor.
Set up this way, the compressor will only run when I'm in the shop and that row of lights is on. Compressor is disabled whenever I leave the shop for any length of time.
Saves wear and tear on the pressure switch since it now only switches the low amperage power to the contactor coil.

 

[pitterpat]

This is pretty much what I did with mine, I've got a contactor with a 120V coil.
Ran a wire off one of my rows of lights to control the coil via the pressure switch. Power from the lights, to the pressure switch which then feeds the pull-in coil on the contactor.
Set up this way, the compressor will only run when I'm in the shop and that row of lights is on. Compressor is disabled whenever I leave the shop for any length of time.
Saves wear and tear on the pressure switch since it now only switches the low amperage power to the contactor coil.

Thanks for the info but for me this sounds way too complicated.

Why can't I just put it on a.switch in my 4 gang box..... just real simple w/o all the other stuff. Not trying to put down what you did just trying to learn?

 

[tdkkart]

Why can't I just put it on a.switch in my 4 gang box..... just real simple w/o all the other stuff. Not trying to put down what you did just trying to learn?

For the same reason your car has a relay(solenoid or contactor) between the starter and the ignition switch. The starting load of a high current starter motor or compressor motor will destroy the contacts in an ignition switch or light switch is short order, the contacts simply aren't heavy enough.

A motor contactor is just another version of a relay. A low current electromagnet or pull-in coil is controlled by the activating switch, the coil then pulls in the contactor containing larger heavy duty contact points.

 

[dgreen1069]

Maybe we aren't clear on what you want to do. My compressor is controlled by a wall switch, but the switch controls the outlet, not the actual compressor. If you have access to the wiring, that's the way to go. I switched the bottom outlet my compressor is plugged into and left the top outlet hot.

 

[Charles (in GA)]

Its a 240v circuit. The OP would need to use a DOUBLE POLE switch, so as to interrupt both sides of the 240v circuit. Thus two hot wires and a ground into the gang box, and two hots and a ground out of the gang box to the receptacle the compressor is plugged into. The switch would need to be amp rated high enough for the circuit in question, and HORSEPOWER rated for the actual horsepower of the motor (not the pesudo HP the manufacturer may have labeled the compressor with).

A Leviton double pole switch such as the 1222 series would be a double pole 20amp rated switch with (at 240v) a 2 hp motor rating, 16 amps max for a motor. I think Hubbell uses the same numbering system.

A Leviton double pole switch such as the 3032 series would be a double pole 30 amp rated switch, with (at 240v) a 2 hp motor rating but with a 24 amp max for the motor.

Leviton and Hubbell switches (and possibly other brands) are readily identified by amperage, using their color. Blue is 15 amp, red is 20 amp and green is 30 amp.

Problem is the OP says the compressor has a 240v plug with ONE blade sideways. This is a 20 amp 240v plug, otherwise identified as a NEMA 6-20 configuration, and a NEMA 6-20 receptacle SHOULD NOT be used on a 15 amp circuit.

Question to the OP? is the circuit wired with 12 gauge wire, or 14 gauge wire? If the circuit is wired ENTIRELY WITH 12 gauge wire, and has the NEMA 6-20 receptacle, you would do well to replace the circuit breaker with a 20 amp breaker to match the rest of the components in the circuit. If 14 gauge wire were used, you need to remove the NEMA 6-20 receptacle and use a 6-15 receptacle which has both blades crossways.

NEMA 6-15 receptacle

Issue with this is the compressor would not plug into it, but that becomes the point of having correct components in a circuit.

Having a proper HP rating switch is also important. Many times that info is either marked on the box, or on the strap of the switch, or found in the manufacturers literature for the component.

I doubt you could overfill the gang box with two hots in and out, but one does need to consider box fill as there may be many other circuits in the box also.

Charles

 

[pitterpat]

Maybe we aren't clear on what you want to do. My compressor is controlled by a wall switch, but the switch controls the outlet, not the actual compressor. If you have access to the wiring, that's the way to go. I switched the bottom outlet my compressor is plugged into and left the top outlet hot.

That is what I want to do....just wanted to make sure that it is ok/ safe to do that.
Thanks!

 

[pitterpat]

Its a 240v circuit. The OP would need to use a DOUBLE POLE switch, so as to interrupt both sides of the 240v circuit. Thus two hot wires and a ground into the gang box, and two hots and a ground out of the gang box to the receptacle the compressor is plugged into. The switch would need to be amp rated high enough for the circuit in question, and HORSEPOWER rated for the actual horsepower of the motor (not the pesudo HP the manufacturer may have labeled the compressor with).

A Leviton double pole switch such as the 1222 series would be a double pole 20amp rated switch with (at 240v) a 2 hp motor rating, 16 amps max for a motor. I think Hubbell uses the same numbering system.

A Leviton double pole switch such as the 3032 series would be a double pole 30 amp rated switch, with (at 240v) a 2 hp motor rating but with a 24 amp max for the motor.

Leviton and Hubbell switches (and possibly other brands) are readily identified by amperage, using their color. Blue is 15 amp, red is 20 amp and green is 30 amp.

Problem is the OP says the compressor has a 240v plug with ONE blade sideways. This is a 20 amp 240v plug, otherwise identified as a NEMA 6-20 configuration, and a NEMA 6-20 receptacle SHOULD NOT be used on a 15 amp circuit.

Question to the OP? is the circuit wired with 12 gauge wire, or 14 gauge wire? If the circuit is wired ENTIRELY WITH 12 gauge wire, and has the NEMA 6-20 receptacle, you would do well to replace the circuit breaker with a 20 amp breaker to match the rest of the components in the circuit. If 14 gauge wire were used, you need to remove the NEMA 6-20 receptacle and use a 6-15 receptacle which has both blades crossways.

NEMA 6-15 receptacle

Issue with this is the compressor would not plug into it, but that becomes the point of having correct components in a circuit.

Having a proper HP rating switch is also important. Many times that info is either marked on the box, or on the strap of the switch, or found in the manufacturers literature for the component.

I doubt you could overfill the gang box with two hots in and out, but one does need to consider box fill as there may be many other circuits in the box also.

Charles

1st, Charles I answered your question about circuit amperage with the answer of what would be the amperage of the compressor.....the compressor is 15 amp...but the circuit is 20 amp. I thought you meant the amperage of the compressor, sorry for the confusion.

Ok, here is what it is:
20 amp circuit
12-2 wire labeled to show both hot
NEMA 6-20 outlet

And here are the pictures:
That is a 20 amp breaker, I just didn't get the 20 amp marking in the pic and it is too cold to go back out. See the black tape on the neutral wire.

The outlet

This is gang box I want to put it in.

Ok, I just want to control the outlet from the switch. And yes, I did use Wago's in this box; I originally had a wire nut on the wires in the box but when I saw the 6 position Wago's at Menards I bought them for this. I'm glad I did because when I took off the wire nuts not all of the wires were evenly in the wire nut.

I'm assuming since I have cleared up what I actually have that it is safe to control the compressor outlet from a switch in the 4 gang box.
Also, all of the circuits in this garage are 20 amp or larger, even just for outlets and all of the wiring for the outlets is 12-2, except for the one for the spot welder which is on a 50 amp breaker with the correct corresponding outlet and wire.

 

[Charles (in GA)]

Well, my discussion about switches still stands, just ignore the part about wire gauges and receptacles and plugs, as you have clarified that.

You need a double pole switch that is rated for at least 20 amps and is a horsepower rated switch. I am guessing that your compressor is probably not over 2 hp though its possible that it is as much as 3 hp.

As I said, bring both hots into the box, to each side of the switch, and take both hots out of the box from the switch.

Leviton 1222-2I Ivory double pole 20 amp switch that is (if you look at the Leviton site), motor rated. A single switch from FruitRidgeTools will only have about $3 or $4 shipping, so it is no more expensive than the big box store, and possibly cheaper.

 

[fstbusa]

That what I did. Compressor is mounted up high, the angle of the pic you can't see the switch but it's on the wall just below the sign to the left of the shelving. Used a 20A motor rated switch.

 

[mzy4v1]

I see a picture on your tool box taken at Deal's Gap!!

 

[fstbusa]

I see a picture on your tool box taken at Deal's Gap!!

Either you know the place very well or you are taking a guess based on the dragon sign there.

 

[mzy4v1]

Either you know the place very well or you are taking a guess based on the dragon sign there.

I have ridden it more than my fair share of times...and I think I have stood in the same spot to take pictures myself

 

[theoldwizard1]

Re: Any peoblem with this:Switch for compressor

You need a switch that is rated for the HP of the compressor.

Like a 20 amp switch?

NO !

There are heavy duty switches that are horsepower rated, not just current (amps), like the following:

Leviton 3032-2 30 Amp, 120/277 Volt, Toggle Double-Pole AC Quiet Switch, Extra Heavy Duty Spec Grade, Self Grounding, Back and Side Wired, Brown

Even though this is a 30A switch, in the Leviton Catalog it is only listed for a 2 hp motor.

This one is rated for 5 HP.

Leviton MS302-DS 30 Amp, 600 Volt, Double- Pole, Single Phase AC Motor Starter, Suitable as Motor Disconnect, Industrial Grade, Non-Grounding, Black


Both of the above switches are double pole so that interrupt both hots as they should !