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 20 MVA 60 MVA 50 MVA 10 MVA 20 MVA 60 MVA 50 MVA 10 MVA ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Short circuit kVA = Base kVA/%X
DGVCL Exam Paper (11-12-2011) In carrier current protection, the purpose of the wave trap is for Trapping power frequency waves 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. ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) An IDMT relay provides An inverse characteristic for low values of the fault current and a definite time characteristic for high values of the fault current A definite time cuttent characteristic A definite time characteristic for low values of the failt current and an inverse characteristic for high values of the fault current An inverse time current characteristic An inverse characteristic for low values of the fault current and a definite time characteristic for high values of the fault current A definite time cuttent characteristic A definite time characteristic for low values of the failt current and an inverse characteristic for high values of the fault current An inverse time current characteristic 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 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 proportional to the square of the armature current 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 Its torque is proportional to the square of the armature current and speed is directional proporational to torque Torque and speed are proportional to the square of the armature current Torque and speed are inversely 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) An over excited synchronous motor draws current at Depends on nature of load Leading power factor Lagging power factor Unity power factor Depends on nature of load Leading power factor Lagging power factor Unity 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) The form factor in AC means the ration of Peak value to average value Peak value to r.m.s value R.M.S. value to average value R.M.S. value to peak value Peak value to average value Peak value to r.m.s value R.M.S. value to average value R.M.S. value to peak value ANSWER DOWNLOAD EXAMIANS APP
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