Electrical Machines Induction motors provided with open slots have more breakdown torque. less breakdown torque. leading power factor. higher efficiency. more breakdown torque. less breakdown torque. leading power factor. higher efficiency. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following motors DC excitation is not required? 3-phase synchronous motor reluctance motor hysteresis motor 3-phase synchronous generator 3-phase synchronous motor reluctance motor hysteresis motor 3-phase synchronous generator ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the source voltage of a DC motor is increased, which of the following will decrease? Full load current. Operating speed. Starting torque, operating speed, full load current. Starting torque. Full load current. Operating speed. Starting torque, operating speed, full load current. Starting torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements about commutating poles which are fitted on most large dc Shunt motors: 1. The commutating poles are placed in the geometric neutral plane and their number is usually Equal to the number of main poles 2. The winding on the commutating poles is connected in series with the shunt-field winding on the main poles 3. The polarity of the commutating pole must be that of the next pole further ahead 4. The commutating poles neutralize the reactance voltage produced in the coil undergoing Commutation. Of these statements, 1 and 4 are correct 1, 2 and 3 are correct 2, 3 and 4 are correct 1, 2 and 4 are correct 1 and 4 are correct 1, 2 and 3 are correct 2, 3 and 4 are correct 1, 2 and 4 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To have sparkless commutation, the armature reaction effect in a DC machine is neutralized by increasing field excitation. compensating winding and commutating poles. shifting the brush axis from GNA to MNA. fixing the brush axis inline with the pole axis. increasing field excitation. compensating winding and commutating poles. shifting the brush axis from GNA to MNA. fixing the brush axis inline with the pole axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Semi closed slots or totally closed slots are used in induction motors, essentially to increase pull out torque improve starting torque reduce magnetising current and improve power factor decrease starting torque increase pull out torque improve starting torque reduce magnetising current and improve power factor decrease starting torque ANSWER DOWNLOAD EXAMIANS APP
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