When doing the wiring in my new garage addition, I planned for a future two post cars lift. I failed to adequately check out the power requirement for said lift. I ran 3-#12 wire+ground wire from the sub-panel to the site about 30 ft away. Now I find that on all the lifts (so far) available, they have a 30 Amp motor. I know that #12 wire is rated for 20 Amps max. My next door neighbor, who is an electrician, says I will have to run the circuit with #10 wire. In my dark heart, I know that he is probably right, but in my ignorance, I was thinking that each of the hot wires would carry one leg of the 220, resulting in 15 Amps per wire. I just want someone to confirm his opinion, and give me the bad news. That will cause me to put the new wires on the outside of my new sheetrock, or try to find a lift with <20Amp power. Thank you.

The bad news is the neighbr is correct, #10 wire is needed for a 30 amp circuit. A 30 amp circuit means that each live wire may carry up to 30 amps, and the load does not get " split" as you perceive.

What is the actual supply voltage and the voltage rating of the new motor? 220 volts is not correct if your located in North America.

Also, what is the horsepower of the new motor?

With the information requested, we can deterimine what size circuit is required for the motor.

I went on several lift sites. On most they had the following: 2HP 220V SP; 208/230V 2HP 1PH. One site, with a 7000Lb capacity(less than the others) had more detail: 2HP 208/230V 1PH 60HZ Max full amp load of 17.4 Amps @208V & 14.6 Amps @230V. I hope that this is the information that you needed. Thank you for your help.

OK I will assume your supply voltage is 240 volts. Everything I see you have posted will work fine on a 20 amp 240 volt circuit.

On the smaller lift that draws <15 amps @ 230 volt requiring a 20 Amp circuit would work with my #12 wire, correct? As a side question, I have seen 220V, 230V, and 240V used interchangeably. Can I assume that 240V is THE correct voltage used in the US for stoves, and water heaters etc? Thank you for making me search, and find a slightly smaller lift that will get the job done, and not cause a rewiring job. You are the man.

240 volts is the standad voltage single phase in North America. Motors are rated from 200 volts up, but usually 208 volts to 240 volts. The amp draw is inversely proportionate, meaning as the supply voltage rises that amp draw reduces. The most popular rating is 230 volts, works fine with 208 or 240. This is for most general purpose motors.