What does it mean if you say a electric motor only works at a certain percent?
Answer:
It is the percent efficiency from converting electrical energy to mechanical energy with the rest being lost as heat. My understanding is that a good motor is something like 96% efficient so 30% sounds pretty bad.
Whoa! Only 30%? That number is WAY out of the ballpark. Today, motors run around 95% efficient at the job of converting electrical energy into motion, with the other 5% being lost to friction and heating. AC motors are a little bit more efficient than DC motors. Synchronous AC motors are a little bit more efficient than AC induction motors.
If you are talking about a variable frequency drive, then I would say that 30% is ok, but not quite as low as they go. A VFD runs the motor at lower speeds by changing the frequency of the power going to the motor. For instance you could drive a 1800RPM motor designed at 60Hz at 900RPM if you could turn the frequency down to 30Hz. You can't run a motor down to 1Hz though, the motor will not get cooled in the normal way and will overheat and fail.
If you are talking about the motor only being designed to run 30% of the time, then its not a motor designed for continuous duty. Motors are designed to run a certian percentage of the time. Continuous duty rated motors are designed to run 100% of a 24hr day, and other motors are designed to run only 8 hrs of a 24hr day, or maybe less.
If either of these is what your freind is talking about then its a problem with the design of the motor, and there is not much you can do.Hope this helps.
The answers post by the user, for information only, FunQA.com does not guarantee the right.
More Questions and Answers: