Welcome. My name is XXXXX XXXXX would be glad to assist.
Personally, I would use a standard 120 volt coil contactor. No reason or benefit using a low voltage and just adds to expense and equipment that can fail.
The dust collector probably is a little high in current to use a small relay, and I would suggest a lighting style contactor to control the power.
We do this is child care/adult care environments, connecting the stoves through a contactor, so that when the fire system is initiated, it turns off power. Yours would be a little different as you are turning it on when something else takes place.
What you want to do is this: Run your 220 volts with ground from the circuit breaker to a box large enough to house the contactor. Then from the contactor to the receptacle for the dust collector. Then run your 120 volts to your control and to the contactor coil. So, when you apply 120 volts to the contactor, it makes and turns on power to the dust collector. I dont know what you are using to control the coil on the contactor, but it just needs to make and break the hot wire, neutral would connect straight through to the coil
First of all, thank you so much for your fast (and helpful) response! Wow! Even with a figure! I'm very grateful for the thoroughness of your reply, so thank you for that.
FYI, although I saw your reply shortly after it came in, the web browser I am using at work is ancient and would not let me type a reply.
I appreciate the confirmation that there's nothing wrong with using standard 110/120V to power the contactor coil. Every resource I've seen that discusses what I'm trying to do talks about stepping down the voltage and using thermostat wire, but I didn't see the point. As you said, more expense and more chance for failure.
Only two minor things left. I'm assuming the inspector will want a "means of disconnect" near the receptacle, so I was intending to purchase a small shutoff box and install it between the breaker panel and the contactor. Do you think that's unnecessary? Something like:
Last thing, you suggested a lighting style contactor. Is there something that makes it more appropriate than other styles of contactors? I was originally intending to get one of the following:
Thank you so much again for your help. I really appreciate it. (I would submit the rating now, but I wasn't sure if that would close the question out and prevent my reply from going though. :)