State the function of following parts of slip ring induction motor: (i) Slip ring (ii) Fan (iii) Brushes (iv) Frame

State the function of following parts of slip ring induction motor: (i) Slip ring (ii) Fan (iii) Brushes (iv) Frame
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1 Answer

Answer :

Sr. No.
Name of part
Function
1 Slip ring
1) The rotor winding terminals are permanently connected to the slip rings. 2) Connects external resistance to rotor circuit through brushes.
2 Fan
1) The fan is connected at the one end of the rotor shaft. Its function is to provide cooling to the motor. 2) For air circulation.
3 Brushes
The brushes are pressed against slip ring. These are used to make connection between external resistance with rotor circuit. 
4 Frame
1) It provides mechanical support to the entire internal parts of motor. 2) Protects the inner parts.
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Last Answer : (D) 75 r.p.m.