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Question:

what is Contnous rating of an AC motor?

If the volts and amp (rms) have been given on continous basis..Is it electrical load/input a motor can sustain?If HP is given tehn woud it be shaft power

Answer:

The load at which it runs continuously without getting overheated
Continuous means that the motor may be run at full load continuously. It is not an intermittent-duty motor. The horsepower (HP) rating is the mechanical output power that the motor can deliver at the shaft. Volts is the nominal voltage at which the motor is designed to run. Usually there is a +/-10% tolerance on that value. Amps is the value of current that the motor will draw when the motor is mechanically loaded to 100%, with rated voltage and frequency applied to the motor.
Almost all AC motors have a label with the information you need. The voltage shown is the voltage required. The Amperage shown Running Load Amps (RLA), or Full Load Amps (FLA) is the power it will draw at it's rated load. Example: Typical ?hp Cap Start 1750rpm 60hz induction motor will show 8.0 RLA, 48.0 Locked Rotor Amperes (LRA) This motor draws 48 Amperes @ 120V for a little less than one second while starting. The current might drop to 3.5 Amperes no load and rise to 8.0 Amperes at the rated ?hp load. If you measure current you will find that excess load draws current beyond the motor's rating which results in overheating and shutdown if it is thermally protected (as it should be). Motors must be matched to Voltage available, ambient temperature and conditions, required starting torque, duty cycle, required power at speed, and numerous other factors.

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