DGVCL Exam Paper (11-12-2011) Which lightning stroke is most dangerous? Direct stroke on line conductor Direct stoke on tower top Direct stroke on ground wire Indirect stroke on conductor Direct stroke on line conductor Direct stoke on tower top Direct stroke on ground wire Indirect stroke on conductor ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Due to skin effect Current flows through the half cross section of the conductor Portion of the conductor near the surface carries less current and the core of the conductor carries more current Uniform current flows through the conductor Portion of the conductor near the surface carries more current and the core of the conductor carries less current Current flows through the half cross section of the conductor Portion of the conductor near the surface carries less current and the core of the conductor carries more current Uniform current flows through the conductor Portion of the conductor near the surface carries more current and the core of the conductor carries less current ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Skin Effect:tendency of the current to crowd near the conductor surface.Skin effect is proportional to frequency, conductor diameter and permiability. Skin effect increases effective resistance of conductor.In DC, no skin effect.
DGVCL Exam Paper (11-12-2011) A Mho relay is a Directional restrained over current relay Voltage restrained directional relay Directional restrained over voltage relay Voltage controlled over current relay Directional restrained over current relay Voltage restrained directional relay Directional restrained over voltage relay Voltage controlled over current relay ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) The picture on the monitor of a computer is made up of tiny coloured dots called Pixels Spots Icons Points Pixels Spots Icons Points ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Under operating conditions, the secondary of a current transformer is always short ciruited because It avoids core saturation and high voltage induction It protects the primary ciruits It is safe to human beings It protects the secondary ciruits It avoids core saturation and high voltage induction It protects the primary ciruits It is safe to human beings It protects the secondary ciruits 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 Magnetizing inrush current Unbalanced protection Lightning Switching over voltages Magnetizing inrush current Unbalanced protection Lightning 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