DGVCL Exam Paper (11-12-2011) In carrier current protection, the purpose of the wave trap is for Tripping fault current All of these Trapping high frequency waves entering into generator/transformer unit. Trapping power frequency waves Tripping fault current All of these Trapping high frequency waves entering into generator/transformer unit. Trapping power frequency waves 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 0.4 % 5 % 6 % 4 % 0.4 % 5 % 6 % 4 % 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) First zone distance relay protects the transmission line section upto 50 % of its full length Its full length 25 % of its full length 80 % of its full length 50 % of its full length Its full length 25 % of its full length 80 % of its full length ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Two parallel conductors are carrying the current in the same direction. Which of the following statements is correct? There is an attracting force between the conductors There is a repelling force between the conductors The force increases when the distance between the conductors is decreased The force increases when the distance between the conductors is increased There is an attracting force between the conductors There is a repelling force between the conductors The force increases when the distance between the conductors is decreased The force increases when the distance between the conductors is increased ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) DC series motors are best suited for traction work because Its torque is proportional to the square of the armature current and speed is directional proporational to torque Torque and speed are inversely proportional to the square of the armature current Its torque is proportional to the square of the armature current and speed is inversely proportional to torque Torque and speed are proportional to the square of the armature current Its torque is proportional to the square of the armature current and speed is directional proporational to torque Torque and speed are inversely proportional to the square of the armature current Its torque is proportional to the square of the armature current and speed is inversely proportional to torque Torque and speed are proportional to the square of the armature current ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Torque in d.c motor = k* φ * IaIn series motor φ α IaTα I²N α 1/φN α 1/T
DGVCL Exam Paper (11-12-2011) Which type of back up protection is widely used for the protection of transmission lines? Control backup Relay backup Remote backup Breaker backup Control backup Relay backup Remote backup Breaker backup ANSWER DOWNLOAD EXAMIANS APP