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 10 MVA 50 MVA 60 MVA 20 MVA 10 MVA 50 MVA 60 MVA 20 MVA ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Short circuit kVA = Base kVA/%X
DGVCL Exam Paper (11-12-2011) In the protection of transformers, harmonic restraint is used to guard against Magnetizing inrush current Lightning Switching over voltages Unbalanced protection Magnetizing inrush current Lightning Switching over voltages Unbalanced protection ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Initial inrush of magnetizing currents have high component of even and odd harmonics.2nd - 63%3rd -26.8%4th- 5.1%5th- 4.1%6th- 3.77th-2.4
DGVCL Exam Paper (11-12-2011) The transient stability of a power system can be improved by Single pole switching of circuit breakers Phase shifting transformer Excitation control Increasing the turbine valve opening Single pole switching of circuit breakers Phase shifting transformer Excitation control Increasing the turbine valve opening ANSWER DOWNLOAD EXAMIANS APP
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 Trapping high frequency waves entering into generator/transformer unit. All of these Trapping power frequency waves Tripping fault current Trapping high frequency waves entering into generator/transformer unit. All of these ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) If a relay fails to operate inspite of a fault in its own zone of protection, it is said to Reach Pick up Under reach Over reach Reach Pick up Under reach Over reach ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) The effect of electric shock on the human body depends on Current Duration of contact All of these Voltage Current Duration of contact All of these Voltage ANSWER DOWNLOAD EXAMIANS APP
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