DGVCL Exam Paper (11-12-2011) Rated making capacity of a ciruit breaker is equal to Rated symmetrical breaking capacity √2 X rated symmetrical breaking capacity 1.11 X rated symmetrical breaking capacity 2.55 X rated symmetrical breaking capacity Rated symmetrical breaking capacity √2 X rated symmetrical breaking capacity 1.11 X rated symmetrical breaking capacity 2.55 X rated symmetrical breaking capacity ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) In the protection of transformers, harmonic restraint is used to guard against Switching over voltages Magnetizing inrush current Unbalanced protection Lightning Switching over voltages Magnetizing inrush current Unbalanced protection Lightning ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Initial inrush of magnetizing currents have high component of even and odd harmonics.2nd - 63%3rd -26.8%4th- 5.1%5th- 4.1%6th- 3.77th-2.4
DGVCL Exam Paper (11-12-2011) Buchholz relay causes Tripping for minor faults and alarm for major faults Alarm for both major and minor faults Tripping for major faults and alarm for minor faults Tripping for both major and minor faults Tripping for minor faults and alarm for major faults Alarm for both major and minor faults Tripping for major faults and alarm for minor faults Tripping for both major and minor faults ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) The purpose of interpoles in DC machines is to nullify The reactance voltage Both the cross-magnetizing mmf and the reactance voltage The cross-magnetizing effect of armature mmf The demagnetizing effect of armature mmf The reactance voltage Both the cross-magnetizing mmf and the reactance voltage The cross-magnetizing effect of armature mmf The demagnetizing effect of armature mmf ANSWER EXPLANATION DOWNLOAD EXAMIANS APP interpoles is widely use to improve commutationplace between main poles fitted to yokefunctions:to neutralize armature mmf in commutating zoneto produce some flux in commutating zone
DGVCL Exam Paper (11-12-2011) If a relay fails to operate inspite of a fault in its own zone of protection, it is said to Reach Pick up Over reach Under reach Reach Pick up Over reach Under reach ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Bulk power transmission over long HVDC lines are preferred on account of Minimum line power losses Low cost of HVDC terminals No harmonic problems Simple protection Minimum line power losses Low cost of HVDC terminals No harmonic problems Simple protection ANSWER DOWNLOAD EXAMIANS APP
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