A Base Load Power Plant supplies for how many hours per day: 8 12 16 24 Correct answer: 4. 24 A Baseload power plant continuously supplies electric power throughout the day.
For same power rating, the size of AC Generator is _____________ DC Generator: Smaller than Larger than Identical to None of these Correct answer: 1. Smaller Explanation: AC generators or alternators are more efficient than dc generators and for same power rating the size of ac generator is smaller than dc generator.
What is the limit for voltage variation at consumer terminals: ± 1% of the declared voltage ± 3% of the declared voltage ± 6% of the declared voltage ± 10% of the declared voltage Correct answer: 3. ±6% of the declared voltage The limit for voltage variation at consumer terminals is ±6% of the declared … Read more
Backup protection functions when: Secondary protection fails Primary protection fails Tertiary protection fails None of the above Correct answer: 2. Primary protection fails
MCQ Statement: If C is the capacitance per phase for delta connected capacitor bank, then what will be capacitance per phase for star connected capacitor bank: C/3 3C C/√3 √3/C Correct answer: 2. 3C Solution: QC = V.IC where IC = V/XC QC = V. V/XC = V2/XC = V2 ωC or C = QC/ … Read more
A 220/1100 V transformer takes no load current of 7 A and absorbs 200 W. What is value of magnetizing current: 4.89 A 5.89 A 6.94 A 7.33 A Correct answer: 3. 6.94 A Solution: Active components of current = IW = W0/V1 = 200/220 = 0.90 A Magnetizing current = √(Io2 – Iw2) = … Read more
A three-phase wound rotor induction motor is preferred for which of the following application: Speed control High starting torque High rotor resistance is required during running No rotor resistance is required in starting Correct answer: 2. High starting torque More Multiple choice questions on Induction motor
A 480/1100 V transformer absorbs 250 W. What is the active component of current: 0.22 A 0.38 A 0.487 A 0.52 A Correct answer: 4. 0.52 A Solution: Active components of current = IW = W0/V1 = 250/480 = 0.52 A
The starting torque of 3 phase induction motor is maximum at which value of rotor power factor: 0.3 lag 0.685 lag 0.707 lag None of above Correct answer: 3. 0.707 lag Explanation: Rotor power factor is mathematically expressed as: R.PF = R2/√(R22 + X22) Rotor power factor is maximum when R2 = X2 R.PF = … Read more
Synchronous generator MCQ Part 8 The power factor of individual alternator operating along other alternators When a number of alternators are operating in parallel, the power factor at which each alternator operated depends on: Driving torque provided by prime mover Field excitation Power factor of load All of the above Correct answer: 2. Field excitation … Read more