Electrical Machines The function of field regulator in a DC compound motor is to vary the armature resistance. none of above. limit the armature current. control field current. vary the armature resistance. none of above. limit the armature current. control field current. 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, 2 and 3 are correct 1, 2 and 4 are correct 1 and 4 are correct 2, 3 and 4 are correct 1, 2 and 3 are correct 1, 2 and 4 are correct 1 and 4 are correct 2, 3 and 4 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4-pole dc generator runs at 1500 rpm. The frequencyof current in the armature winding is 25 Hz 0 Hz 50 Hz 100 Hz 25 Hz 0 Hz 50 Hz 100 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Transformer action requires a alternating magnetic lux. increasing magnetic flux. alternating electric flux. constant magnetic flux. alternating magnetic lux. increasing magnetic flux. alternating electric flux. constant magnetic flux. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the armature current of 5 Amp is flowing through the dc motor the torque produced is 47 Nm. Keeping the speed constant if the armature current is increased to 7 amp, calculate the new torque. Assume losses to be constant. 27.73 Nm . 38.5 Nm. 65.8 Nm. 74 Nm. 27.73 Nm . 38.5 Nm. 65.8 Nm. 74 Nm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The voltmeter connected across a generator reads voltage same at no load and at full load (rated). The generator is of the type level compound. series generator. shunt generator. short - shunt generator. level compound. series generator. shunt generator. short - shunt generator. ANSWER DOWNLOAD EXAMIANS APP
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