Electrical Machines Resistance commutation is used generally in case of None of these fractional kW DC machines. DC machines above 10 kW. DC machines bellow 5 kW. None of these fractional kW DC machines. DC machines above 10 kW. DC machines bellow 5 kW. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the emf generated by a 4 pole Lap connected DC Motor rotating at 1500 rpm having 1000 conductors and useful flux per pole is 0.4 mWb. 30 volts. 10 volts. 40 volts. 20 volts. 30 volts. 10 volts. 40 volts. 20 volts. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The external resistance to be added in the armature circuit to limit the armature current to 125% of its rated value is 31.1 Ω 15.1 Ω 31.9 Ω 15.9 Ω 31.1 Ω 15.1 Ω 31.9 Ω 15.9 Ω 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 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 1 and 4 are correct 1, 2 and 3 are correct 2, 3 and 4 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines CRGO steel is used in the core of transformer to reduce hysteresis loss. ohmic loss. both eddy current and hysteresis loss. eddy current loss. hysteresis loss. ohmic loss. both eddy current and hysteresis loss. eddy current loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In salient pole synchronous machine, maximum power occurs at a load angle of less than 90° 0° Greater than 90° 90° less than 90° 0° Greater than 90° 90° ANSWER DOWNLOAD EXAMIANS APP
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