Electrical Machines DC motors are stopped by opening line switches and not by forcing the handle of the motor starter back to OFF position. This is due to occurance of Heavy sparking at the first stud of starting resistance steps. Both of above. Heavy sparking at brushes. None of these. Heavy sparking at the first stud of starting resistance steps. Both of above. Heavy sparking at brushes. None of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V dc series motor takes 40 A when giving its rated output at 1500 rpm. Its resistance is 0.3 Ω. The value of resistance which must be added to obtain rated torque at 1000 rpm is 5.7 Ω 1.9 Ω 6 Ω 2.2 Ω 5.7 Ω 1.9 Ω 6 Ω 2.2 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motor has negative speed regulation? Cumulative compound motors Shunt motor Differential compound motor Series motor Cumulative compound motors Shunt motor Differential compound motor Series motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Magnetic field of a DC generator is produced by what? None of the options. Permanent magnets. Both B and C. Electromagnets. None of the options. Permanent magnets. Both B and C. Electromagnets. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two single-phase alternators operating in parallel have induced EMFs on open circuit of 230∠0° and 230∠10° volts and respective reactance of j2 Ω j3 Ω calculate the terminal voltage 150 V. 200 V. 300 V. 223.V. 150 V. 200 V. 300 V. 223.V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole wave wound dc motor having flux per pole of 9.56 X 10-3 Wb contains 460 armature conductors with armature resistance of 0.6 ohm. Calculate the starting current flowing through the armature if the supply voltage is 240 volt. 800 Amp. 400 Amp. 320 Amp. 0.5 Amp. 800 Amp. 400 Amp. 320 Amp. 0.5 Amp. ANSWER DOWNLOAD EXAMIANS APP
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