DGVCL Exam Paper (11-12-2011) If the excitation of a synchronous generator fails, it acts as a Induction generator Synchronous motor Synchronous generator Induction motor Induction generator Synchronous motor Synchronous generator Induction motor ANSWER EXPLANATION DOWNLOAD EXAMIANS APP if excitation of synchronous generator fails, operate as induction motor
DGVCL Exam Paper (11-12-2011) A 3 phase, 6 pole induction motor operates on 440 V, 50 Hz, supply. If the actual speed of the motor is 960 rpm the slip will be 6 % 4 % 0.4 % 5 % 6 % 4 % 0.4 % 5 % ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Ns = 120f/PSlip=(Ns-Nr)/NsNs = 1000 and Nr = 960 from equation of slip, S = (1000-960)/1000S = 0.04 or 4%
DGVCL Exam Paper (11-12-2011) The transient stability of a power system can be improved by Increasing the turbine valve opening Single pole switching of circuit breakers Phase shifting transformer Excitation control Increasing the turbine valve opening Single pole switching of circuit breakers Phase shifting transformer Excitation control ANSWER DOWNLOAD EXAMIANS APP
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 Remote backup Control backup Breaker backup Relay backup Remote backup Control backup ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) A fuse wire should have High specific resistance and high melting point Low specific resistance and high melting point High specific resistance and low melting point Low specific resistance and low melting point High specific resistance and high melting point Low specific resistance and high melting point High specific resistance and low melting point Low specific resistance and low melting point ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Which lightning stroke is most dangerous? Direct stroke on ground wire Direct stroke on line conductor Indirect stroke on conductor Direct stoke on tower top Direct stroke on ground wire Direct stroke on line conductor Indirect stroke on conductor Direct stoke on tower top ANSWER DOWNLOAD EXAMIANS APP
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