Q.1
A protection system engineer is planning to provide the complete protection, he can achieve this by ___________
  • a) three phase fault relays and two earth fault relays
  • b) two phase fault relays and three earth fault relays
  • c) a two phase fault relays and three earth fault relays
  • d) a two phase fault relays and two earth fault relays
Q.2
The given figure shows protection system scheme for one phase of generator. A high resistance fault occurs near the neutral end with the current distribution as marked. The slope of the relay isand pick-up current of 0.15A.
  • a) True
  • b) False
Q.3
We need the biasing of differential relay biased to avoid mal operation when used for transformer protection due to ____________
  • a) mismatch of CT
  • b) saturation of
  • c) difference in connection of both sides of CT
  • d) current setting mismatch
Q.4
If the specified fault setting for a winding is mentioned as 20%, then what can be inferred about it?
  • a) If a terminal fault has its current limited to the full load rating, then 20% of winding from neutral end will be unprotected
  • b) If a terminal fault has its current limited to the full load rating, then 80% of winding from neutral end will carry current
  • c) If a terminal fault has its voltage limited to the full load rating, then 20% of winding from neutral end will be unprotected
  • d) Any of the mentioned
Q.5
The typical characteristic of the relay during loss of excitation is ____________
Questionpower-systems-questions-answers5.jpg
  • a)
  • b)
  • c)
  • d)
Q.6
The standard system fault characteristic of the relay is _____________
Questionpower-systems-questions-answers6.jpg
  • a)
  • b)
  • c)
  • d)
Q.7
A longitudinal differential protection on stator can detect inter-turn on the stator.
  • a) True
  • b) False
Q.8
Bias is used in the relay protection to _______________
  • a) provide balanced sharing of current
  • b) reduce current level
  • c) deivert the current
  • d) none of the mentioned
Q.9
Unbalancing of an alternator may occur due to ____________
  • a) single phase fault
  • b) unbalanced loading
  • c) line breaking
  • d) all of the mentioned
Q.10
For the given earth fault for solidly earthed CT, the fault current as a percentage of the full load current is given as _______________
Questionpower-systems-questions-answers10.jpg
  • a)
  • b)
  • c)
  • d)
0 h : 0 m : 1 s