DGVCL Exam Paper (11-12-2011) If the dielectric strength of the medium between the contacts builds up more rapidly than the restriking voltage the arc will Increase in size Extinguish Decrease in size Restrike Increase in size Extinguish Decrease in size Restrike 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 Simple protection Low cost of HVDC terminals No harmonic problems Minimum line power losses Simple protection Low cost of HVDC terminals No harmonic problems ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) In the protection of transformers, harmonic restraint is used to guard against Lightning Switching over voltages Magnetizing inrush current Unbalanced protection Lightning Switching over voltages Magnetizing inrush current Unbalanced protection 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) 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% 80 % Less than 90% 90 % More than 90% 80 % Less than 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) People can interact with each other through any part of the world through video conferencing using Joystick Webcam Speaker Scanner Joystick Webcam Speaker Scanner ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) An IDMT relay provides An inverse characteristic for low values of the fault current and a definite time characteristic for high values of the fault current A definite time characteristic for low values of the failt current and an inverse characteristic for high values of the fault current A definite time cuttent characteristic An inverse time current characteristic An inverse characteristic for low values of the fault current and a definite time characteristic for high values of the fault current A definite time characteristic for low values of the failt current and an inverse characteristic for high values of the fault current A definite time cuttent characteristic An inverse time current characteristic ANSWER DOWNLOAD EXAMIANS APP
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