Carrier Corp.
Att'n: Mike Bellomo
516 W. 34th St.
New York, NY 10001

Mike –

Here are two 277 volt test controls. The internal transformer is a 240 volt unit. It works well. Runs cool, et.. I should be getting some 277 volt transformer samples in soon. It shouldn't make any difference in the operation, but we have to get ETL to pass the unit.
I don't like it in the high-speed tap. I've run the 277 volt motor for over a week at very low speed in the medium speed tap. Works great. Smooth, quiet and cool.

Suggestion: So long as you are modulating the motor's speed, you don't need a three speed motor. You could have the motor manufacturer build a single-speed motor that is full of copper and iron. Much higher efficiency ball bearing motor. Better operation. Etc. My suggestion: is to contact the specialty motor division of Baldor Electric. The building will probably fall down before the motor dies.

Hope this helps,

Best regards,
Dick Peters, P.E./CM