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Figure 8.3 (a) Squirrel-cage-type rotor; (b) stator and rotor circuits (i) squirrel-cage type, (ii) slip-
ring type; (c) slip-ring-type induction motor-stator and rotor circuits
By connecting extra resistance in the rotor circuit during starting, very high
starting torque can be developed in slip-ring motors. For squirrel-cage rotor,
it is not possible to add any extra resistance in the rotor as the circuit is closed
by itself permanently and no terminals are brought out.
8.3 WINDINGS AND POLE FORMATION
