Abstract： AS 60034.12:2009 pdf download.Rotating electrical machines Part 12: Starting performance of single-speed three-phase cage induction motors. 3.3 pull-up torque (Ta) the smallest steady-state asynchronous torque which the motor develops betwe...

AS 60034.12:2009 pdf download.Rotating electrical machines Part 12: Starting performance of single-speed three-phase cage induction motors.

3.3

pull-up torque (Ta)

the smallest steady-state asynchronous torque which the motor develops between zero speed and the speed which corresponds to the

breakdown torque, when the motor is supplied at the rated voltage and frequency.

This definition does not apply to those motors of which the torque continually decreases with increase in speed.

NOTE In addition to the steady-state asynchronous torques, harmonic synchronous torques, which are a function of rotor load angle. will be present at specific speeds At such speeds, the accelerating torque may be negative for some rolor load angles Experience

and calculation show this to be an unstable operating condition and therefore harmonic synchronous torques do not prevent motor

acceleration and are excluded from this definition.

3.4

breakdown torque (Tb)

the maximum steady-state asynchronous torque which the motor develops without an abrupt drop in speed. when the motor is supplied

at the rated voltage and frequency.

This definItion does not apply to those motors of which the torque continually decreases with increase in speed.

3.5

rated output

the value of the output included in the rating

3.6

locked rotor apparent power (S1)

the apparent power input with the motor held at rest at rated voltage and frequency.

Recommended：