Remote Switch for My Air Compressor?

[RonRock]

So for nearly 30 years I have used the 30 amp 240v double pole single throw breaker to turn on my air compressor in morning and off at night. Works perfect, and I know that there is no power to the compressor as long as I remember to power it off at days end. The compressor is up above in the loft, accessible but not easily reached daily. No real reason for a change, but convenience may be good.

I have a couple 30 amp 240V contactors on hand. One is 120v control the other is 24V control. I keep these on hand for AC replacements.

Is there any benefit to using one or the other? I know that the 24v is low voltage which would make wiring a switch very easy. But that also requires a transformer, no big deal I have those on hand also. Just wondering if there is any reason for one over the other in a shop air compressor system. Actually considering some kind of internet connection for control, but that just seems excessive. Fun, but not needed.

 

[exranger06]

The 120V contactor will require a neutral wire to be ran with the hot legs from the breaker panel to the contactor, if you don't already have one (likely not).

 

[RonRock]

The 120V contactor will require a neutral wire to be ran with the hot legs from the breaker panel to the contactor, if you don't already have one (likely not).

I'll have to check on that. Pretty sure I do.

 

[msharley]

So for nearly 30 years I have used the 30 amp 240v double pole single throw breaker to turn on my air compressor in morning and off at night. Works perfect, and I know that there is no power to the compressor as long as I remember to power it off at days end. The compressor is up above in the loft, accessible but not easily reached daily. No real reason for a change, but convenience may be good.

I have a couple 30 amp 240V contactors on hand. One is 120v control the other is 24V control. I keep these on hand for AC replacements.

Is there any benefit to using one or the other? I know that the 24v is low voltage which would make wiring a switch very easy. But that also requires a transformer, no big deal I have those on hand also. Just wondering if there is any reason for one over the other in a shop air compressor system. Actually considering some kind of internet connection for control, but that just seems excessive. Fun, but not needed.

Why fix what ain't broke?

FORGIVE ME! This is GJ!

I will stand in the corner and write COGSWELL COGS on the black board 100 times!

 

[wyliesdiesels]

any contactor you use will need to be HP rated.

whats the HP rating on the motor nameplate?

how is it currently connected?

 

[RonRock]

any contactor you use will need to be HP rated.

whats the HP rating on the motor nameplate?

how is it currently connected?

Good thinking. I was only considering Amperage rating. I'll have to take a look at the motor plate, and the contactors.

Currently connected from my breaker box 30A breaker to a disconnect box near the compressor to the compressor pressure switch.

I will report back tomorrow. As often happens I got re-directed with family needs today.

 

[RonRock]

Why fix what ain't broke?

FORGIVE ME! This is GJ!

I will stand in the corner and write COGSWELL COGS on the black board 100 times!

You do have a valid point.

One of the reasons for the change is simple convenience. Getting tired of leaning over the bench to reach the breaker. My first thought was to finally put a switch near the exit door. Then again, I have been doing it as I have for so long I may have a problem with the change. Haha. So maybe an internet capable control is worth consideration. But then I'm getting way carried away. So on one hand WTF! On the other, Leave it alone, KISS.

I guess that sometimes I just like to make changes for change's sake. Or maybe not. Easy enough to do either way.

But the original question still remains. Pretty sure I'll do one or the other.

 

[Metal-Marc]

I've been lectured about this by a friend electrician. It's not a good idea to use a breaker as an on/off switch. It weakens the internal spring.

 

[nadogail]

I would use a wall wart to provide 24 Volts to a relay and a low voltage switch to control the relay. In the garage where Mrs Nadogail sometimes works it occasionally gets chilly.

The heater is controlled by a Manually Operated Spring Driven Timer, this ensures that the heater will stop running when 30 Minutes has passed or the knob is turned again. I did this so that she will not walk away and forget the 5KW heater was left running.

One School House I taught at had the Classroom Lights and Air Conditioning on a Two Hour Spring Driven Timer.

 

[cabranch47]

I used a hp rated contactor for power to the compressor. 120V coil wired to my shop lights. Lights on - compressor on, lights off-compressor off. Don't have to worry about remembering to turn it off/on. It has been working fine for several years. I just do not turn the lights off while the compressor is running to avoid hard startups.

 

[RonRock]

I used a hp rated contactor for power to the compressor. 120V coil wired to my shop lights. Lights on - compressor on, lights off-compressor off. Don't have to worry about remembering to turn it off/on. It has been working fine for several years. I just do not turn the lights off while the compressor is running to avoid hard startups.

Good idea. I like it.

Sounds like my new plan.

 

[BillK]

I've been lectured about this by a friend electrician. It's not a good idea to use a breaker as an on/off switch. It weakens the internal spring.

I have been doing it every day for almost 35 years at my business. I turn it on when I walk in the door in the morning and off when I leave at night. 3 Phase 5hp motor on my compressor. Have yet to have to replace a breaker

 

[Metal-Marc]

I have been doing it every day for almost 35 years at my business. I turn it on when I walk in the door in the morning and off when I leave at night. 3 Phase 5hp motor on my compressor. Have yet to have to replace a breaker

I'll send you my friend so he can lecture you as well.

 

[dave*99]

I remember years ago seeing breakers labeled SWD. Switching duty. Here is an article on where they were used/allowed.

What Does SWD Mean on a Circuit Breaker? SWD vs HID

What does SWD mean on a circuit breaker? Read on to learn why some are rated for it and its characteristics.

www.galvinpower.org

 

[Max]

If I was going to wire up a switch and contactor, I’d wire up an indicator at the switch so I knew the contactor/compressor was on. There is nothing like a red light to help you remember…

 

[exranger06]

If I was going to wire up a switch and contactor, I’d wire up an indicator at the switch so I knew the contactor/compressor was on. There is nothing like a red light to help you remember…

That's exactly what I did, although my light is green, not red. Very handy since my compressor is in another room and I can't even hear it running when I'm in the garage.

 

[Bert_]

I've been lectured about this by a friend electrician. It's not a good idea to use a breaker as an on/off switch. It weakens the internal spring.

Yes it will wear out a breaker. Doesn't make it a bad idea. I do it pretty often with single phase auger motors. Stab in breakers up to 60A are dirt cheap and you can replace many of them before you get to the price of a disconnect or a contactor.

 

[RonRock]

Been using mine for nearly 30 years pretty much daily. I was aware that they said not to use a breaker as a switch. Like you said Bert breakers are cheap, and it had a side benefit of breaking any electrical current to the compressor when off. Not a big deal, but a plus.

Had a family emergency so haven't been able to check the compressor motor, but I did remember having some other contactors on hand. I have a AB 3 Phase contactor with 120v control and rated for 5 hp 230v. So it will work.

I like the idea of controlling it with the lighting switch. Pretty sure that's the plan. Thanks cabranch47 for the idea.

Cheers,
Ron

​

 

[MOS3522]

If your compressor hook up is leak free, why stress about leaving it on at night? It shouldn't need to run at all if it has pressure.

 

[wyliesdiesels]

If your compressor hook up is leak free, why stress about leaving it on at night? It shouldn't need to run at all if it has pressure.

Because connections, hoses etc can blow out

 

[gba2331]

I just turn off the valve at the output of my compressor.