i want to be able to turn my 220v dust collector on AND off from two places; ie from my table saw area or from my band saw area. how do i wire this up with a two wire plus ground cable? note i do not need to turn the system on from one place and off from another.
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of course, you know that white wires are only supposed to be used for neutral.
(which is a call for use of three conductor plus ground cable)
the simple way to do what you want is to use two double pole switches, something like a leviton 1222-2.
you will need to wire power (two phases, or two hot wires) to each switch, and then from each switch, two additional hot wires to the power for the dust collector. keep the color code consistent, if you cross them you will blow a breaker when both switches are on.
If you want to do this with only a single two conductor wire to each switch, a relay is what you need.
what size wire are you planning to use?
what is the rating of the blower?
Can you specify where the power source is you plan to use, and how far away the switch locations are?
The requirement that white wires be used only for neutral is fairly recent (at least to people of my age). Code used to allow white wires to be taped or painted black (or some other color other than gray) and care one leg of 240v circuits.
Code trivia. Prior to that code change, residential clothes dryers required a 2 wire plus ground circuit. In this circuit the ground wire actually served as the neutral for the timer, a very very low wattage load. Afterward the circuit required a # 10 wire for the neutral when all that was really necessary was a 240 volt timer. A cost to the manufacturer of zero.
Hi Mike; we seem to be on the same page with this project; ie I was planning to control the supple power with two DPDT switches, using 12 AWG 2 CDRS 300 volt cable. The switches are 10 and 20 feet away from the collector's outlet. As to the blower it uses a 2hp, single phase 220 volt, 9.5 amp motor.
How about a centrally located relay? Seems simpler.
yes it is looking that way.
Guess you already have power to the blower.
hooking up the switches will take 60 feet of cable. (more if your distance is not cable run length but rather distance as you walk around the shop)
You can route the power to the switches from either the breaker box, or from where the blower outlet is now. Could even run one from where it is, and one from the breaker box.
depending on how big the box the existing outlet is, you might want to add another box, and use one for the outlet, and one for the wiring connections.
I just mention the wire color because someone pointed it out to me on the forum.
If it was my shop, I would use the 12-2 with ground, and slap some black or even better, red tape on the white wires.
Don't tell anyone, but this is what I did at my sister's house. I ran a dedicated 12-2 WG NM cable from the breaker box to her bathroom for use with a heated floor in her small bathroom. Instead of installing a 120 volt version, the tile guy put in a 220 volt in-floor heating element , (and wisely said he would not hook it up) so rather than run more cable, I put some black tape on both ends of the white conductor and moved the wires inside the breaker box. I lucked out as the last empty space in the box was open, next to the space I had used for the dedicated 120 volt breaker, which let me move the neutral wire from the buss bar to the other side of a 240 volt breaker without having to find a wire stretcher.
I trust you will be careful to make the new wire runs protected from damage, and well supported.
Do you have this on a dedicated 20 amp circuit? Before you turn the breaker back on when it is all wired, check that the hot sides are isolated from each other with the switches in the on position just to be sure.
Did you run the wire from the breaker box to the blower outlet?
I have 30 amps to work with, and I used 12-2 cable to the dust collector outlet. I am working in a 2 car garage so not a lot of room to work with. I will look for a relay controlled outlet set up. What about grounding the plastic duct system, any suggestions ?