Clifford, Close! An electric motor is rated at 746 Watts per horse power. There is a very complete Wikipedia article on the subject which I found interesting.
Usually most home circuits are 15 amps and for practical purposes one cannot really generate more than about a horse and a half. As you say though, these things aren't reliably rated, they use optimistic calculations. My compressor claims to be 5 HP. I have it on it's own 15 amp breaker and it does sometimes kick it out on start-up but it isn't anything like 5 HP. That takes 220 V at 15 amps at least. 20 amps should happily run a treadmill and probably 15 amps but if there is a substantial other load you might trip the breaker starting off on a steep incline. ----- Original Message ----- From: clifford To: [email protected] Sent: Monday, October 05, 2009 9:04 PM Subject: [BlindHandyMan] electric motor question Dear David: If my memory serves, and it is getting stubborn about that, one horse power equals 760 watts which would result in roughly 7 amps per horse power when running. Most motors require at least a third more power when starting, and if it is starting under load, that can go up a bit. A twenty amp circuit should be sufficient to power the motor. I do believe there are several appliances on the market that claim two plus horse power, however I doubt that some of them are as powerful as claimed. The rated amps should be on the motor unless it was manufactured back in the good old days when it was not a criminal offense to remove a tag from a pillow. Yours Truly, Clifford Wilson Ps. I was assuming that you were talking about a motor running on 110 volts. [Non-text portions of this message have been removed] [Non-text portions of this message have been removed]
