Power System Protection MCQs Part 2
Power System Protection MCQs Part 2
Contents
- 1 In case of fault it is often desired that frame leakage protection should trip
- 2 The correct equation for an effectively grounded system is
- 3 Buchholz relay is used to protect
- 4 Generally, the carrier current protection scheme is recommended for
- 5 SF6 gas is ____________
- 6 The under-voltage relay is recommended for
- 7 ____________________ is/are an instantaneous relay/s
- 8 Statement: SF6 circuit breakers have very short arcing time
- 9 Plug setting multiplier is defined as the ratio of
- 10 High-speed circuit breakers result in
In case of fault it is often desired that frame leakage protection should trip
a. In case of fault it is often desired that frame leakage protection should trip:
- Half the installed breakers
- Only one breaker
- All connected breakers
- Two breakers
Correct answer: 3. All connected breakers
The correct equation for an effectively grounded system is
b. The correct equation for an effectively grounded system is:
- X0/X1 < 3.0
- X0/X1 > 3.0
- X0/X1 > 2.0
- 3.0 < X0/X1< 9.0
Correct answer: 1. X0/X1 < 3.0
Buchholz relay is used to protect
c. Buchholz relay is used to protect:
- Alternator
- Induction Motors
- Synchronous motors
- Transformers
Correct answer: 4. Transformers
Generally, the carrier current protection scheme is recommended for
d. Generally, the carrier current protection scheme is recommended for:
- HV cables
- HV transmission lines
- Both of these
- None of these
Correct answer: 2. HV transmission lines
SF6 gas is ____________
e. SF6 gas is ____________:
- Highly inflammable
- Non-inflammable
Correct answer: 3. Non-inflammable
The under-voltage relay is recommended for
f. The under-voltage relay is recommended for:
- Transformers
- Motors
- Feeder
- Busbars
Correct answer: 2. Motors
____________________ is/are an instantaneous relay/s
g. ____________________ is/are an instantaneous relay/s:
- PMMC type
- Shaded pole type
- Both of these
- None of these
Correct answer: 1. PMMC type
Statement: SF6 circuit breakers have very short arcing time
h. Statement: SF6 circuit breakers have very short arcing time.
Utterance: SF6 circuit breakers are costly.
- Both statement and utterance are correct
- Both are wrong
- The statement is correct, the utterance is wrong
- The statement is wrong, the utterance is correct
Correct answer: 1. Both statement and utterance are correct
Plug setting multiplier is defined as the ratio of
i. Plug setting multiplier is defined as the ratio of:
- Fault current in relay coil x Pick up current
- Fault current in relay coil / Pick up current
- Fault current in relay coil x Transformer secondary turns
- Fault current in relay coil / Transformer secondary turns
Correct answer: 2. Fault current in relay coil / Pick up current
High-speed circuit breakers result in
j. High-speed circuit breakers result in:
- Increased stability of power systems
- Decreased stability of the power system
Correct answer: 2. Decreased stability of the power system
Continue reading:
- Power System Protection MCQs Part 1
- Power System Protection MCQs Part 2
- Power System Protection MCQs Part 3
- Power System Protection MCQs Part 4
- Power System Protection MCQs Part 5
- Power System Protection MCQs Part 6
- Power System Protection MCQs Part 7
- Power System Protection MCQs Part 8
- Power System Protection MCQs Part 9
- Power System Protection MCQs Part 10