DGVCL Exam Paper (11-12-2011) DC series motors are best suited for traction work because Torque and speed are inversely proportional to the square of the armature current 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 inversely proportional to torque 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 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 inversely proportional to torque Its torque is proportional to the square of the armature current and speed is directional proporational to torque 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) Bulk power transmission over long HVDC lines are preferred on account of No harmonic problems 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 ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) In which of the following motors, the stator and rotor magnetic fields rotate at the same speed? Induction motor Synchronous motor Reluctance motor Universal motor Induction motor Synchronous motor Reluctance motor Universal motor ANSWER EXPLANATION DOWNLOAD EXAMIANS APP In all machine stator and rotor magnetic field rotates (stationary with respect to each other) at synchronous speed with respect to stationary observer.
DGVCL Exam Paper (11-12-2011) Rated making capacity of a ciruit breaker is equal to 2.55 X rated symmetrical breaking capacity √2 X rated symmetrical breaking capacity 1.11 X rated symmetrical breaking capacity Rated symmetrical breaking capacity 2.55 X rated symmetrical breaking capacity √2 X rated symmetrical breaking capacity 1.11 X rated symmetrical breaking capacity Rated symmetrical breaking capacity ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Which motor is used to start heavy loads? Cumulatively compounded motor Differentially compounded motor Shunt motor Series motor Cumulatively compounded motor Differentially compounded motor Shunt motor Series 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) Reactance relay is used to protect against Phase faults only Over voltage faults Earth faults only Both phase and earth faults Phase faults only Over voltage faults Earth faults only Both phase and earth faults ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS