HIGH VOLTAGE ENGINEERING

1. During impulse withstand test the impulse applied to the insulator is:

• 1. 1/50 μ sec

• 2. 0.1/0.05 μ sec

• 2. 0.1/0.05 μ sec

• 4. 0.001/50 μ sec

Marx multistage impulse generator model involves:

• 1. High ohmic resistances

• 2. Low ohmic resistances

• 3. Both of these

• 4. None of these

Usually, the impulse voltage is:

• 1. Unidirectional

• 2. Bidirectional

• 3. Tridirectional

• 4. Quadridirectional

The standard shape of impulse wave as specified by the American standard is 1.5/40 μsec. The number 1.5 is:

• 1. Wave front

• 2. Wave tail

• 3. Wave head

• Wave footing

The small load current in Cockroft – Walton circuit means:

• 1. Voltage drop is very large

• 2. Voltage drop is small

• 3. None of these

• 4. Can’t predict

The dielectric strength of liquids is of the order:

• 1. 100 kV/cm

• 2. 1000 kV/cm

• 3. 5000 kV/cm

• 4. 10000 kV/cm

The rectifier which generates high voltage d.c from a.c:

• 1. Half-wave rectifiers

• 2. Full wave rectifiers

• 3. Voltage doubler type rectifiers

• 4. All of these

The term counterpoise in high voltage engineering is referred to:

• 1. A large-sized sphere gap

• 2. Galvanized wire which runs in parallel to the overhead line

• 3. A surge arrester which is installed at distribution station

• 4. None of these

The standard shape of impulse wave as specified by the American standard is 1.5/40 μsec. The number 40 is:

• 1. Wave front

• 2. Wave tail

• 3. Wave head

• 4. Wave footing

____________ is the input to impulse generator:

• 1. DC Supply

• 2. AC Supply

• 3. Impulse

• 4. Triangular a.c