DGVCL Exam Paper (11-12-2011) In a power plant, a reserve generating capacity which is not in service but is in operation is known as Cold reserve Firm power Hot reserve Spinning reserve Cold reserve Firm power Hot reserve Spinning reserve ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) The main advantage of using fractional pitch winding is to refuce Size of the machine Cost of the machine Amount of copper in the winding Harmonics in the generated emf Size of the machine Cost of the machine Amount of copper in the winding Harmonics in the generated emf ANSWER EXPLANATION DOWNLOAD EXAMIANS APP due to fractional pitch EMF can be approximately made into sine wavelosses due to harmonics reducedsaving in conductor materialmechanical strength of coil is increased.
DGVCL Exam Paper (11-12-2011) Reactance relay is used to protect against Both phase and earth faults Earth faults only Phase faults only Over voltage faults Both phase and earth faults Earth faults only Phase faults only Over voltage faults ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) An AC series circuit has R = 6 Ω, XL = 20 Ω and Xc = 12 Ω. The ciruit power factor will be 0.6 leading 0.6 lagging 0.5 leading 0.8 lagging 0.6 leading 0.6 lagging 0.5 leading 0.8 lagging ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Which motor is used to start heavy loads? Series motor Shunt motor Cumulatively compounded motor Differentially compounded motor Series motor Shunt motor Cumulatively compounded motor Differentially 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) 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 directional proporational to torque Its torque is proportional to the square of the armature current and speed is inversely proportional 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 directional proporational to torque Its torque is proportional to the square of the armature current and speed is inversely proportional 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