DGVCL Exam Paper (11-12-2011) Which type of back up protection is widely used for the protection of transmission lines? Breaker backup Relay backup Control backup Remote backup Breaker backup Relay backup Control backup Remote backup 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) Which motor is used to start heavy loads? Series motor Shunt motor Differentially compounded motor Cumulatively compounded motor Series motor Shunt motor Differentially compounded motor Cumulatively compounded motor ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Torque in d.c motor = k* φ * IaIn series motor φ α IaTα I²starting torque of dc series motor is high
DGVCL Exam Paper (11-12-2011) Permittivity is expressed in terms of Weber /m farad/sq. m. N/m Farad/m Weber /m farad/sq. m. N/m Farad/m ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) If the excitation of a synchronous generator fails, it acts as a Synchronous motor Synchronous generator Induction motor Induction generator Synchronous motor Synchronous generator Induction motor Induction generator ANSWER EXPLANATION DOWNLOAD EXAMIANS APP if excitation of synchronous generator fails, operate as induction motor
DGVCL Exam Paper (11-12-2011) A device connected to the computer which converts digital signals to analog and vice-versa is Keyboard Modem UPS CPU Keyboard Modem UPS CPU ANSWER DOWNLOAD EXAMIANS APP
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