DGVCL Exam Paper (11-12-2011) An over excited synchronous motor draws current at Lagging power factor Leading power factor Unity power factor Depends on nature of load Lagging power factor Leading power factor Unity power factor Depends on nature of load ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Over excitation : leading currentUnder excitation : lagging currentNormal excitation : current with unity PF (in phase current)
DGVCL Exam Paper (11-12-2011) At time t= 0+ , with zero initial condition, which of the following acts as a short circuit? Conductor Capacitor Resistor Voltage source Conductor Capacitor Resistor Voltage source ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) The picture on the monitor of a computer is made up of tiny coloured dots called Pixels Spots Icons Points Pixels Spots Icons Points ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Buchholz relay causes Alarm for both major and minor faults Tripping for minor faults and alarm for major faults Tripping for major faults and alarm for minor faults Tripping for both major and minor faults Alarm for both major and minor faults Tripping for minor faults and alarm for major 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 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 More than 90% 80 % Less than 90% 90 % More than 90% 80 % Less than 90% 90 % 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) Hysteresis in an instrument means The reliability of the instrument The repeatability of the instrument The inaccuracy due to change in temperature The change in the same reading when the input is first increased and then decreased The reliability of the instrument The repeatability of the instrument The inaccuracy due to change in temperature The change in the same reading when the input is first increased and then decreased ANSWER DOWNLOAD EXAMIANS APP
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