# 3-phase transformers which cannot be connected in  parallel are

1.  YY with ` `

2.   Y? with ?Y

3.   YY with Y?

4.   None of these

4

YY with Y?

Explanation :
No Explanation available for this question

# The order of the sub harmonic during SSR for 50Hz normal frequency is

1.  25 Hz

2.   16 2/3 Hz

3.   10 Hz

4.  None of these

4

None of these

Explanation :
No Explanation available for this question

# The non uniform distribution of voltage across the units in a string of suspension type insulators is due to

1.  Unequal self capacitance of the units

2.  Non uniform of distance of separation of the units from the tower body

3.  The existence of stray capacitance between the metallic junctions of the units and the tower body

4.  Non uniform distance between the cross arm and the units

4

The existence of stray capacitance between the metallic junctions of the units and the tower body

Explanation :
No Explanation available for this question

# When ever the conductors are dead ended of there is a change in the direction of transmission line, the insulators used are the

1.  Pin type

2.  Suspension type

3.   Strain type

4.     Shackle type

4

Strain type

Explanation :
No Explanation available for this question

# The time taken for a surge to travel a 600 km long overhead transmission line is

1.  6s

2.   1s

3.   0.02s

4.      0.002s

4

0.002s

Explanation :
No Explanation available for this question

# A balanced 3-phase 3-wire supply feeds balanced star connected resisters. If one of the resistors wire is disconnected then the percentage reduction in load will be

1.  33 ½

2.   50

3.  66 2/3

4.   75

4

50

Explanation :
No Explanation available for this question

# A long over head transmission line is terminated by its characteristic impedance. Under this operating condition, the ratio of voltage to the current at different points along the line will

1.  Progressively increase from the sending end to receiving end

2.  Progressively increase from the receiving end to sending end

3.  Remain the same at two ends but be higher between the two ends being maximum at the centre of the line

4.  Remain same at all points

4

Remain same at all points

Explanation :
No Explanation available for this question

# For a transmission line with negligible losses, the lagging reactive power (VAR) delivered at the receiving end, for a given receiving end voltage is directly proportional to the

1.  Square of the line voltage drop

2.  Line voltage drop

3.  Line inductive reactance

4.  Line capacitive reactance

4

Line voltage drop

Explanation :
No Explanation available for this question

# Corona loss can be reduced by the use of hollow conductors because

1.  The current density is reduced

2.  The eddy current in the conductor is eliminated

3.  For a given cross section, the radius of the conductor is increased

4.  Of better ventilation in the conductor

4

For a given cross section, the radius of the conductor is increased

Explanation :
No Explanation available for this question

# Shunt compensation in an EHV line is used

1.  Improve stability

2.  Reduce fault level

3.  Improve the voltage profile

4.  Substitute for synchronous phase modifier

4