DGVCL Exam Paper (12-06-2016) What will happen if the primary of a transformer is connected to DC supply? Transformer may start to smoke and burn No effect Transformer will operate with low efficiency Transformer will operate with high efficiency Transformer may start to smoke and burn No effect Transformer will operate with low efficiency Transformer will operate with high efficiency ANSWER EXPLANATION DOWNLOAD EXAMIANS APP transformer works on principle of faraday's law of electromagnetic induction. So if D.C supply use, no indction are produced and due to this E.M.F not induced in winding and transfer of electrical energy is not possible.
DGVCL Exam Paper (12-06-2016) The rating of fuse wire is always expressed in _____ kWh Ampere-hours Ampere-volts Amperes kWh Ampere-hours Ampere-volts Amperes ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Equipment :Rating Fuse : AmpereTransformer : kVAAlternator : kVAMotor : kW/HPBattery : ampere-hour
DGVCL Exam Paper (12-06-2016) The time of closing the cycle, in modern circuit breakers is 0.001 sec. 0.003 sec. 0.01 sec. 0.1 sec. 0.001 sec. 0.003 sec. 0.01 sec. 0.1 sec. ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (12-06-2016) Reactance relay is used for protection against: Phase fault None of these Earth fault Over voltage fault Phase fault None of these Earth fault Over voltage fault ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (12-06-2016) The kVA rating of Three-phase transformer with Voltage = 200 V and Current = 100 A will be : 75 kVA 34.64 kVA 20 kVA None of these 75 kVA 34.64 kVA 20 kVA None of these ANSWER EXPLANATION DOWNLOAD EXAMIANS APP For three phase,VA = √3 V IFor single phase, kVA = V I
DGVCL Exam Paper (12-06-2016) The voltage of transmission can be regulated by Switching in shunt capacitors at the receiving end during heavy loads Use of tap changing transformers Use of capacitors to neutralize the effect of series reactance Any of the above methods Switching in shunt capacitors at the receiving end during heavy loads Use of tap changing transformers Use of capacitors to neutralize the effect of series reactance Any of the above methods ANSWER DOWNLOAD EXAMIANS APP
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