Electrical Machines Under which of the following conditions hunting of synchronous motor is likely to occur ? Over-loading for long period. Periodic variation of load. Over-excitation. Small and constant load. Over-loading for long period. Periodic variation of load. Over-excitation. Small and constant load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The ___________________ generator has the poorest voltage regulation. over compounded. differential compounded. shunt. under-compounded. over compounded. differential compounded. shunt. under-compounded. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Maximum allowable tan - delta (tanδ) of dielectric dispassion factor of power transformer insulating oil is generally taken as 1 at 90°C. 3 at 90°C. 2 at 90°C. 0.5 at 90°C. 1 at 90°C. 3 at 90°C. 2 at 90°C. 0.5 at 90°C. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc machines, the space waveform of the air-gap flux distribution affects both the torque and voltage neither the voltage nor the torque voltage but not the torque torque but not the voltage both the torque and voltage neither the voltage nor the torque voltage but not the torque torque but not the voltage ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A self-excited shunt generator fails to build up, because 1. the field circuit is open 2. The armature circuit is open 3. the residual magnetism is absent 4. The direction of rotation is wrong From these, the correct answer is 3 only 1, 2 and 3 1, 3 1, 2, 3 and 4 3 only 1, 2 and 3 1, 3 1, 2, 3 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements : For a level compounded dc generator to run at constant voltage, the series field mmf must effectively compensate 1. armature reaction mmf 2.armature resistance drop 3. brush contact voltage drop Which of these statements is/are correct ? 2 alone 1 and 2 1, 2 and 3 1 and 3 2 alone 1 and 2 1, 2 and 3 1 and 3 ANSWER DOWNLOAD EXAMIANS APP
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