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 0.5 leading 0.6 lagging 0.8 lagging 0.6 leading 0.5 leading 0.6 lagging 0.8 lagging 0.6 leading ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) First zone distance relay protects the transmission line section upto 80 % of its full length 50 % of its full length 25 % of its full length Its full length 80 % of its full length 50 % of its full length 25 % of its full length Its full length ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) In the protection of transformers, harmonic restraint is used to guard against Switching over voltages Unbalanced protection Lightning Magnetizing inrush current Switching over voltages Unbalanced protection Lightning Magnetizing inrush current 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) An over excited synchronous motor draws current at Leading power factor Depends on nature of load Lagging power factor Unity power factor Leading power factor Depends on nature of load 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 purpose of providing a choke in a tube light is To eliminate corona effect To limit the current to an appropriate value To improve the power factor To avoid radio interference To eliminate corona effect To limit the current to an appropriate value To improve the power factor To avoid radio interference 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 Under reach Over reach Pick up Reach Under reach Over reach Pick up ANSWER DOWNLOAD EXAMIANS APP