A.C. squirrel cage induction motor
A.C. squirrel cage induction motor
(OP)
We are currently using two 250 h.p. motors on a coal cutting machine that are rated for 950 volts. Our power supply is 1100 volts, so my question is, is the increase in voltage hence torque going to increase the H.P. the motors develope, because we are encountering overload trips and the motors stalling out on heavy cutting.





RE: A.C. squirrel cage induction motor
I'm not sure about your case. If it is a NEMA design D than there can be substantial change in slip and changing voltage would have a big effect on speed and torque. Also I'm not sure of the torque-speec characteristics of your load.
RE: A.C. squirrel cage induction motor
RE: A.C. squirrel cage induction motor
NEMA ICS1-2000 §4.2
"The 1000-volt utilization voltage applies to equipment installed on 1040Y/600-volt electrical distribution systems typically used in mines."
RE: A.C. squirrel cage induction motor
RE: A.C. squirrel cage induction motor
ehh,
1100/950=1.16
1040/1000=1.04
RE: A.C. squirrel cage induction motor
cbarn brings up a more relevant point that as you increase voltage above nameplate, at some point the current will start increasing due to increase in exciting current (core saturation).
Also with higher voltage you will always expect higher current during starting (but usually lower starting duration)
RE: A.C. squirrel cage induction motor
RE: A.C. squirrel cage induction motor