need an electric motor geek now!!?

Is the motor going to run continuosly?What's the load on the motor?

A motor run below name plate rating gets overheated very quickly.

Hooking to three phase is not an issue. Just use any two hot legs. Where are you reading 205 volts at, the panel or the branch circuit? Motors do hate undervoltage. I have had air compressors on 100 ft, extension cords and the motor could not even get started under a load. If it worries you that much, you can do a couple things. 1. If your breaker panel is feed by a step down transformer (480-208/120 volt) you can move the taps up one notch to boost the voltage about 5 more volts. Or 2. buy a small single phase 208pri - 230sec. transformer to feed just the motor. Unless this is continuous duty, don't worry it should be fine.

The princple of motors are generators and vice versa is not really true. Try spinning any ac induction motor with another motor, and see if you produce any output on the windings. Not gonna happen. unless your rotor is wound and connected electrically you will not produce a magnetic flux in the stator winding.

Going from 208 to 205 is not a problem. The line voltage will vary more than that. However, running a single phase motor on a three phase supply could be a problem. Check with an electrician before doing that. There are ways to balance the load.

Your motor will run fine. The manufacturer probably has a +-10% tolerance.

BTW- The motor will actually run cooler with less voltage. It will also have slightly less torque.

I don't know why I'm getting so many thumbs down. Maybe people think I mean that your motor will run on three phase. I thought it was obvious that you plan to wire your motor to only one of the three phases as this would be your only choice.. Where would you land the other wire?

I gave thumbs up to your first answerer because he is right. I am curious though where you heard that it would be a problem. I mean after all, electric motors are also generators and can work in a pretty wide range.