Electrical Machines What is/are the necessary conditions for parallel operation of alternators? Terminal voltage is same Speed of alternators should be same Both 1and 2 Frequency should be same Terminal voltage is same Speed of alternators should be same Both 1and 2 Frequency should be same ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor is running with a divertor connected across its field winding. If the divertor resistance is reduced then the speed of the motor will remain unaltered. become execessively high. decrease. increase. remain unaltered. become execessively high. decrease. increase. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements : Interpoles in dc machines 1. reducearmature reaction effects in the interpolar region 2. have the same dimension as main polls 3. have their windings connected in series with the armature 4. have same number of turns as the armature 5. have the polarity same as that of the main pole ahead in a motor From these, the correct statements are 1, 3 and 5 1, 2, 3 and 5 1, 2 and 3 1 and 3 1, 3 and 5 1, 2, 3 and 5 1, 2 and 3 1 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole dynamo with wave wound armature has 51 slots contains 20 conductors in each slot. If induced emf 357 Volts and speed is 8500 rpm, flux per pole will be 1.2 mWb. 3.5 mWb. 2.7 mWb. 1.4 mWb. 1.2 mWb. 3.5 mWb. 2.7 mWb. 1.4 mWb. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the necessity of copper brushes in a dc motors? None of these. To absorb the mechanical shocks produced during running condition. To convert alternating supply current to direct current. To increase the flux cutting by the rotor. None of these. To absorb the mechanical shocks produced during running condition. To convert alternating supply current to direct current. To increase the flux cutting by the rotor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In escalator which motor is used? Universal motor. DC shunt motor. 1 - φ IM. 3 - φ IM. Universal motor. DC shunt motor. 1 - φ IM. 3 - φ IM. ANSWER DOWNLOAD EXAMIANS APP