Electrical Machines In a 6 pole DC machine, 90 mechanical degrees correspond to which of the following electrical degree? 45. 180. 270. 30. 45. 180. 270. 30. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Direct-on-line (DOL) starters are not suitable for starting large DC motors, because the motor may run away. the starting current will be enormously high. the motor may not start. the starting torque becomes low. the motor may run away. the starting current will be enormously high. the motor may not start. the starting torque becomes low. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The field divertor resistance for a DC series motor is of order of 10 Ω 50 Ω 100 Ω 0.1 Ω 10 Ω 50 Ω 100 Ω 0.1 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of DC Shunt Motor electromagnetic torque developed is Proportional to the square of armature current. None of above. Inversely proportional to the armature current. Proportional to the armature current. Proportional to the square of armature current. None of above. Inversely proportional to the armature current. Proportional to the armature current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 400 V, 50 Hz, 30 Hp, three phase IM is drawing 50 A current at 0.8 p.f lagging. The stator and rotor copper losses are 1.5 KW and 900 W respectively. The friction and windage losses are 1050 W and core losses are 1200 W. The air gap power of the motor will be 25 kW. 24.11 kW. 26.21 kW. 23.06 kW. 25 kW. 24.11 kW. 26.21 kW. 23.06 kW. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A synchronous generator is feeding a zero power factor (lagging) load at rated current. The armature reaction is magnetizing. demagnetizing. cross – magnetizing. ineffective. magnetizing. demagnetizing. cross – magnetizing. ineffective. ANSWER DOWNLOAD EXAMIANS APP
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