- A 415 V 3 Phase 50 Hz Star Connected Induction Motor Gave The Following Results On No Load And Blocked Rotor Test As 1 (41.51 KiB) Viewed 19 times
A 415 V, 3-phase, 50 Hz, star connected Induction Motor gave the following results on no load and blocked rotor test as follows No load Test: 415 V, 3.5 A, 250 W Blocked rotor Test: 115 V, 13 A, 1660 W Calculate a) the no load power factor b) Core loss and Friction & Windage loss c) Magnetising circuit constants RO and XO in approximate equivalent circuit d) power factor under short circuit e) Equivalent impedance at blocked rotor test
b). A 3 phase induction motor has maximum torque equal to twice of the full load torque. Determine the ration of motor starting torque to its full load torque, if it is started by (i) direct-on-line starter (ii) star-delta starter (iii) auto-transformer starter with 60% tapping. The per phase rotor resistance and standstill reactance is 0.3 12 and 3 respectively. Neglect stator impedance.