Asynchronous slip-ring motor with 50 Hz frequency, 380/220 V with full load values Pn = 50...
Asynchronous slip-ring motor with 50 Hz frequency, 380/220 V
with full load values Pn = 50 HP, nn = 987 rpm, per phase;
- rotor circuit resistance 0.2 ohm,
- the stationary reactance is 0.5 ohm,
- the loadability coefficient is 2.1 and
- the number of pole pairs is 8.
a)Calculate the motor's full load torque, tipping torque and idle
speed and number of revolutions under maximum load.
b)To give the motor a maximum torque, calculate the resistance value that should be included in the rotor circuit.
c)Since the motor drives a workpiece with "Calendar-Moment
Characteristic" at 987 rpm under full load, calculate the
resistance value that must be taken into the rotor-per-phase cycle
to reduce the speed of the drive system to K * d / min.
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Asynchronous slip-ring motor with 50 Hz frequency, 380/220 V
with full load values Pn = 50...
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