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AIM :
To conduct a direct load test on a 3-phase slip ring induction motor and to draw the performance characteristics.
FUSE RATING-
FOR- STATOR- 125% 0f 7.5A = 10A
FOR ROTOR – 125% of 11A = 15A
THEORY:
Slip ring induction motor is also called as phase wound motor. The motor is wound for as many poles as the no. of stator poles and always wound 3-Ф even while the stator is wound two-phase. The other three windings are brought out and connected to three insulated slip-rings mounted on the shaft with brushes resting on them. These three brushes are further externally connected to a three phase star connected rheostat. This makes possible the introduction of an additional resistance in the rotor circuit during starting period for increasing starting torque of the motor.