Electrical Machines A 3 phase stepper motor has 6 stator poles and 4 rotor poles, then find the step angle? 30° 45° 10° 60° 30° 45° 10° 60° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To have sparkless commutation, the armature reaction effect in a DC machine is neutralized by increasing field excitation. shifting the brush axis from GNA to MNA. fixing the brush axis inline with the pole axis. compensating winding and commutating poles. increasing field excitation. shifting the brush axis from GNA to MNA. fixing the brush axis inline with the pole axis. compensating winding and commutating poles. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The result of slip test on a 3-phase, 20 KVA, 400 V, 50 Hz connected salient pole alternator is given below- Phase value: Vmax = 100 V, Vmin = 96 V, Imax = 10 A and I min = 7 A. The direct and quadranature axis reactances are respectively 14.28 and 9.60 Ω. 14.28 and 5.54 Ω. 8.248 and 5.54 Ω. 8.248 and 9.60 Ω. 14.28 and 9.60 Ω. 14.28 and 5.54 Ω. 8.248 and 5.54 Ω. 8.248 and 9.60 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the armature electric current is increased to double its previous value, and the time of commutation is halved, how will the reactance voltage vary? It will be doubled. It will remain the same. It will becomes four times. It will be halved. It will be doubled. It will remain the same. It will becomes four times. It will be halved. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In 3 - Φ induction motor some times copper bars are placed deep in the rotor to improve starting torque. improve efficiency. improve power factor. reduce copper loss. improve starting torque. improve efficiency. improve power factor. reduce copper loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The shaft torque of a dc motor is less than the electromagnetic torque because of eddy current losses. ohmic losses. hysteresis losses. mechanical losses. eddy current losses. ohmic losses. hysteresis losses. mechanical losses. ANSWER DOWNLOAD EXAMIANS APP
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