Electrical Machines A dc shunt generator, when commissioned after a major repair of the field system, failed to build Up voltage. It was because field system lost residual magnetism field winding was wrongly connected there was a break in the armature circuit field resistance was higher than critical resistance field system lost residual magnetism field winding was wrongly connected there was a break in the armature circuit field resistance was higher than critical resistance ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements : Interpoles in dc machines 1. reducearmature reaction effects in the interpolar region 2. have the same dimension as main polls 3. have their windings connected in series with the armature 4. have same number of turns as the armature 5. have the polarity same as that of the main pole ahead in a motor From these, the correct statements are 1, 3 and 5 1 and 3 1, 2, 3 and 5 1, 2 and 3 1, 3 and 5 1 and 3 1, 2, 3 and 5 1, 2 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines On which of the following factor/factors the speed of a DC motor depends upon? Armature current. Applied voltage. All of these. Field flux. Armature current. Applied voltage. All of these. Field flux. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor wound rotor motor is mainly is used in application where low starting torque. high starting torque. less costly motor is not required. power factor is less. low starting torque. high starting torque. less costly motor is not required. power factor is less. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Short circuiting is caused in the armature winding due to failure of insulation between two commutator bars. failure of insulation between two turns of coil. any of above. grounding of two or more turns of the same coil. failure of insulation between two commutator bars. failure of insulation between two turns of coil. any of above. grounding of two or more turns of the same coil. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Slip exists in induction motor. none of above. synchronous motor. in both machines. induction motor. none of above. synchronous motor. in both machines. ANSWER DOWNLOAD EXAMIANS APP
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