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I just got a bandsaw with the 5hp motor that requires a 220v 30amp single phase connection. I have it up and running with a three wire dryer cable to my dryer receptacle. When researching requirements for a new circuit I found out the NEMA 10-30 receptacles have been deprecated. I ordered a 14-30r and 14-30p along with a four wire cable. A video on wiring the cord to the saw showed two loads wires and a green ground. Am I ok leaving the white neutral unconnected?

  • What sort of cable is the existing 10-30 receptacle wired using, and is it wired to the main panel or to a subpanel? – ThreePhaseEel Sep 20 '18 at 11:43
  • I don't recall. It's been 30 years since I installed it. The new circuit is from a sub-panel in my garage. – curt Sep 20 '18 at 17:43
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I am really not sure what you mean by depreciated. So moving on from that we can see if this question can be answered.

Many people get confused with different types of circuits. In your case a 240V circuit or a 120/240V circuit, and these are two different circuits. The 240V circuit (a nominal 220V) requires the use of 240V only. This requires 2 conductors that measure 240V across them and a grounding conductor. A 120/240V piece of equipment requires two different voltages to function. This one requires 2 conductors that measure 240V one conductor the neutral conductor (the white one or identified or grounded) and it measures 120V between the other 2 conductors and a grounding conductor.

The NEMA configuration 14-30 receptacle is a standard design for the 120/240V circuit. There is nothing wrong to use it for a 240V circuit.

That's a long way around to say that the receptacle itself and the circuit really doesn't have to have a neutral if it is a specific duty circuit for the band saw. Even though you might want to install a neutral conductor if you are ever thinking about using the circuit for something other than your band saw.

Stay safe and never work on circuits when they are alive.

  • I read that 10-30 was deprecated on wikepedia: en.wikipedia.org/wiki/NEMA_connector#NEMA_10 – curt Sep 20 '18 at 19:00
  • @curt - My bad I mistook depreciated for deprecated. Yes the nema 10-30 is no longer used except for grandfathered dryers since it is a non grounding receptacle much like the 2-pronged outlet is now a 3-pronged. The proper 240V 30A receptacle would be a nema 6-30. Once again not saying a nema 14-30 wouldn't work. You would just not be using the neutral. – Retired Master Electrician Sep 21 '18 at 13:12
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First, good on you for getting rid of that ratty old hazardous NEMA 10 dryer connection. Things should have grounds, and they shouldn't bootleg ground off neutral.

Once you've wired a NEMA 14 socket, any device that only needs hot hot ground can be wired into a NEMA 14 plug, the neutral pin is simply not connected to anything.

In fact you can just get/make an adapter cord, NEMA 6 female (socket) to NEMA 14 male (plug), and that is legal and safe to use as needed.

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