DGVCL Exam Paper (11-12-2011) First zone distance relay protects the transmission line section upto Its full length 80 % of its full length 50 % of its full length 25 % of its full length Its full length 80 % of its full length 50 % of its full length 25 % of its full length ANSWER DOWNLOAD EXAMIANS APP
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) An over excited synchronous motor draws current at 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 Lagging power factor 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? Voltage source Resistor Capacitor Conductor Voltage source Resistor Capacitor Conductor ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) The advantage of slipring induction motor over the squirrel cage induction motor is It's power factor is higher It can be started with the help of rotor resistances It has a higher efficiency It is suitable for higher speeds It's power factor is higher It can be started with the help of rotor resistances It has a higher efficiency It is suitable for higher speeds ANSWER EXPLANATION DOWNLOAD EXAMIANS APP slip ring motor have high starting torque compare to squirrel cage motor and have good speed controlalso have high over loading capacity, smooth acceleration under heavy loads.
DGVCL Exam Paper (11-12-2011) A device connected to the computer which converts digital signals to analog and vice-versa is Keyboard CPU UPS Modem Keyboard CPU UPS Modem ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS