Need a hand wiring up a 220v motor starter for an air compressor.

So I'm getting ready to wire up my Quincy 325 air compressor with a 7.5hp single phase 220v motor on it. I wired up a 220v single phase outlet on the wall, coming off of a 50a circuit breaker in the breaker box. The 3-prong type 220v outlet has 2 hot wires, and 1 ground wire going to it....no neutral (or common).

Here is the problem. All of the 40a 7.5hp motor starter boxes I've seen have a 120v coil (powered by my pressure switch). The problem I'm running into is that in order to power the coil with 120v single phase, I need 1 hot wire and 1 neutral wire......which I don't have.

So, the way I see it...I have two options. 1. wire up a different 220v outlet box, one of the 4 prong receptacles with 2 hot wires, 1 ground, and 1 neutral wire. Then I can pull 120v power off of 1 hot wire, and 1 neutral wire.

2. I find a 40a motor starter box with a contactor that has a 220v coil. I've looked, but haven't had much luck.

Any other options? What as I missing??

IQRaceworks said:

1. wire up a different 220v outlet box, one of the 4 prong receptacles with 2 hot wires, 1 ground, and 1 neutral wire. Then I can pull 120v power off of 1 hot wire, and 1 neutral wire.

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Pretty much how I would go. However being so big I'm not so sure I would put a plug on it. Slap a fused disconnect on the wall next to it, run some FMC to the starter and go.

Run a separate 120v supply to the starter. Mark the starter for the future that is has two sources of supply.
Or simplest and cleanest is just get a mag with a 240v coil.