Electrical Machines Direct-on-line (DOL) starters are not suitable for starting large DC motors, because the motor may not start. the motor may run away. the starting current will be enormously high. the starting torque becomes low. the motor may not start. the motor may run away. the starting current will be enormously high. the starting torque becomes low. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The self induced emf in the coil undergoing commutation is called the reactance voltage. dynamically induced voltage. statically induced voltage. None of these reactance voltage. dynamically induced voltage. statically induced voltage. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the temperature of armature resistance is increased, the speed of a series motor would decrease. not change. None of above. increase. decrease. not change. None of above. increase. 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 ? 1 and 2 2 alone 1 and 3 1, 2 and 3 1 and 2 2 alone 1 and 3 1, 2 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a standard frequency the machine operates at a particular speed known as normal speed. synchronous speed. any of the above. slip speed. normal speed. synchronous speed. any of the above. slip speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of a DC series motor is Proportional to the square of the armature current. Proportional to field current. Proportional to the armature current. Inversely proportional to the armature current. Proportional to the square of the armature current. Proportional to field current. Proportional to the armature current. Inversely proportional to the armature current. ANSWER DOWNLOAD EXAMIANS APP
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