The effect of adding external resistance in the rotor circuit of 3 ϕ slip ring induction motor is to
1. Increase starting torque
2. decrease starting torque
3. reduce starting current
4. reduce maximum torque
5. improve power factor at starting
Correct statements are :
1
2, 3, 4, 5
2
2, 4, 5
3
1, 3, 4, 5
4
1, 3, 5