DGVCL Exam Paper (11-12-2011) The efficiency of a transformer at full load, 0.8 p.f. lag is 90%. Its efficiency at full load, 0.8 p.f. lead will be 90 % More than 90% Less than 90% 80 % 90 % More than 90% Less than 90% 80 % ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Efficiency= output power/input powerefficiency = (v*i*cosφ)/((v*i*cosφ)+(x² Pc)+(Pi)) x=fractional part of full load
DGVCL Exam Paper (11-12-2011) Bulk power transmission over long HVDC lines are preferred on account of Low cost of HVDC terminals Simple protection Minimum line power losses No harmonic problems Low cost of HVDC terminals Simple protection Minimum line power losses No harmonic problems ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Different computers are connected to a LAN by a cable and a Modem Interface card Telephone line Special wires Modem Interface card Telephone line Special wires ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Two parallel conductors are carrying the current in the same direction. Which of the following statements is correct? The force increases when the distance between the conductors is decreased There is a repelling force between the conductors There is an attracting force between the conductors The force increases when the distance between the conductors is increased The force increases when the distance between the conductors is decreased There is a repelling force between the conductors There is an attracting force between the conductors The force increases when the distance between the conductors is increased ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Buchholz relay causes Tripping for both major and minor faults Alarm for both major and minor faults Tripping for major faults and alarm for minor faults Tripping for minor faults and alarm for major faults Tripping for both major and minor faults Alarm for both major and minor faults Tripping for major faults and alarm for minor faults Tripping for minor faults and alarm for major faults ANSWER DOWNLOAD EXAMIANS APP
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 Under reach Over reach Pick up Reach Under reach Over reach Pick up Reach ANSWER DOWNLOAD EXAMIANS APP
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