Wiring a 240V Appliance

Hint: There are 2 distinctions - old appliances, and pure 240V systems - which used 3 wire plugs. The former is no longer allowed, and was replaced with a 4-wire plug

• This one has a ground and 2 hots on a modern appliance. With 3 wires, it means it has 240v only, but not 120v. [1]
  • See Spruce for difference between 3 wire and 4 wire installation [2]
  • But - older appliances which were 120/240v, not pure 240 - also had a 3-wire cord, and they combined ground with neutral. But that is no longer allowed as it appears to be less safe - for example if in a non-fault condition, the person has lower resistance than the ground. See [3]
• If you only have a 2 conductor + bare ground, mark the bare ground as a neutral and run it to the neutral of the main panel if you want 240V/120V. It is not clear whether codes allow this, or whether this is allowed with subpanels. [4]
• Does a 3-wire 240v circuit have a grounded neutral, or a ground that is neutralized?
• Thus: is it safe to say that any 3-wire appliance is pure 240V no 120V?
• Note: if it says 3 wire or 4 wire is ok - then the device is pure 240, no 120. In the 4 wire case, you just disconnect the neutral, so you have pure 240. Ie, you are just running a 4 wire cable with 3 wires of the 4 available - so that functionally it is identical to the 3 wire case. This is an example of a device that does this: [5]. Manual is consistent in showing 3 working wires and describing the device as 240V only.