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Caleb Dietrich
11-21-2007, 6:53 PM
Hello again,

Quick question. Is it harmfull for the motors of a Dust Collector and a compressor to plug them into a switched outlet, and use that to turn them on and off?

Do I need a special switch for a 20/20 amp 220 feed?

Thanks again...

Caleb
Jason Beam
11-21-2007, 6:59 PM
No and yes. You need a double-pole switch since you need to throw both hot leads. They are a special switch and wouldn't cause you any problem if wired correctly.


Edit: On second thought ... I'm not sure how magnetic switches would like that. If you're using machines with magnetic switches you may have issues. Hopefully someone with more knowledge than I will come along and clarify this.
Jim Becker
11-21-2007, 7:55 PM
A "switched" outlet in this case is not necessarily harmful but in the case of the DC it's not alway best to turn them on and off "frequently". Further, it's probably a better idea to use a contactor to do the "switching" and control it from a 120v or low voltage switch or switches in the shop. Contactors are designed to handle the loads that these kind of tools can generate over time. (Contactors are a type of "relay"...the control side, when voltage is applied, causes a magnetic assembly to move the contacts closed for the load side and provide power to the device)

I use that method with my cyclone. My IR compressor has a built-in switch, but I very rarely turn it off.
Wade Lippman
11-21-2007, 8:27 PM
You need a double pole switch rated for the size of your motor, but other than that it is no problem. I used one on my 2hp DC; I think it was $10 at HD.

My new cyclone came with a magnetic switch which is obviously incompatible with the old switch. I am thinking of wiring around it because I liked the old switch.
Tom Veatch
11-21-2007, 9:30 PM
... On second thought ... I'm not sure how magnetic switches would like that. If you're using machines with magnetic switches you may have issues. Hopefully someone with more knowledge than I will come along and clarify this.

If by "magnetic switch" you're talking about the type of switch that will not restart the machine after a power interruption, then there is a definite issue. The magnetic switch will see opening the "outlet switch" as a power loss. When the outlet switch is closed, the magnetic switch will have to be cycled to restart the machine.
Jason Beam
11-22-2007, 2:34 AM
If by "magnetic switch" you're talking about the type of switch that will not restart the machine after a power interruption, then there is a definite issue. The magnetic switch will see opening the "outlet switch" as a power loss. When the outlet switch is closed, the magnetic switch will have to be cycled to restart the machine.


Aha! That was precisely the concern I'd had. Thanks for clearing that up :)
Caleb Dietrich
11-22-2007, 5:27 PM
To be more specific, I have a 3hp Woodtec dust collector and a 26 gallon campbell hausfeld compressor.
I know the compressor does not "reset" when the power supply is cut. I'm not sure about the Dust collector.
The reason for adding a switch is because the are on the other side of a wall from the main shop area.