DGVCL Exam Paper (11-12-2011) The purpose of providing a choke in a tube light is To eliminate corona effect To improve the power factor To limit the current to an appropriate value To avoid radio interference To eliminate corona effect To improve the power factor To limit the current to an appropriate value To avoid radio interference ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) The circuit breaker generally used in railway traction is Minimum Oil CB Air break CB Vacuum CB Bulk Oil CB Minimum Oil CB Air break CB Vacuum CB Bulk Oil CB ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) The efficiency of a transformer at full load, 0.8 p.f. lag is 90%. Its efficiency at full load, 0.8 p.f. lead will be 80 % 90 % More than 90% Less than 90% 80 % 90 % More than 90% Less than 90% ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Efficiency= output power/input powerefficiency = (v*i*cosφ)/((v*i*cosφ)+(x² Pc)+(Pi)) x=fractional part of full load
DGVCL Exam Paper (11-12-2011) The advantage of slipring induction motor over the squirrel cage induction motor is It is suitable for higher speeds It can be started with the help of rotor resistances It has a higher efficiency It's power factor is higher It is suitable for higher speeds It can be started with the help of rotor resistances It has a higher efficiency It's power factor is higher 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) If the percentage reactance of the system upto the point of fault is 20% and the base kVA is 10,000 the short ciruit kVA is 60 MVA 20 MVA 50 MVA 10 MVA 60 MVA 20 MVA 50 MVA 10 MVA ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Short circuit kVA = Base kVA/%X
DGVCL Exam Paper (11-12-2011) A fixed step by step procedure for finding the solution of a problem on computer is called Software Algorithm Logic Hardware Software Algorithm Logic Hardware ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS