Electrical Machines A transformer has hysteresis loss of 30 W, at 240 V, 60 Hz. The hysteresis loss at 200 V, 50 Hz will be 28 W. 25 W. 30 W. 36 W. 28 W. 25 W. 30 W. 36 W. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Diverters are used only in either of these series motors shunt motors None of these either of these series motors shunt motors None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - φ induction motor running at full load which of these parameters is stationary with respect to the stator mmf wave? Rotor winding. Rotor mmf wave. Both rotor and stator winding. Stator winding. Rotor winding. Rotor mmf wave. Both rotor and stator winding. Stator winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature resistance control method is used for the _______ ? None of these below rated speed both 1 and 2 above rated speed None of these below rated speed both 1 and 2 above rated speed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For 250 volt DC Shunt Motor the armature and field resistance are 0.5 ohm and 250 ohm respectively. What will be the back e.m.f. produced when it takes a load current of 21A. 220 V. 150 V. 280 V. 240 V. 220 V. 150 V. 280 V. 240 V. 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, 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 1, 2 and 3 are correct 1, 2 and 4 are correct 1 and 4 are correct ANSWER DOWNLOAD EXAMIANS APP