Power System Protection MCQ Part 5
Which of following material is used in liquid fuses
Which of following material is used in liquid fuses:
- Water
- SF6
- Transformer oil
- Carbon tetra chloride
Correct answer: 4. Carbon tetra chloride
In star connected system, without neutral ground, the zero sequence currents equal
In star connected system, without neutral ground, the zero sequence currents equal:
- RMS value of phase currents
- Peak value of phase currents
- Zero
Correct answer: 3. Zero
Which of the following can be employed as an interrupting medium in a contactor
Which of the following can be employed as interrupting medium in a contactor:
- Compressed air
- Oil
- SF6 gas
- Any of above
Correct answer: 4. Any of above
Earth fault relays are directional relays
Earth fault relays are directional relays:
- True
- False
Correct answer: 1. True
If the percentage reactance of an element is 30% and the full-load current is 40 A, then short-circuit current will be
If the percentage reactance of an element is 30% and the full-load current is 40 A, then short-circuit current will be:
- 1.33 A
- 13.2 A
- 53.2 A
- 133 A
Correct answer: 4. 133 A Solution: 40 × 100/30 = 133 A