# The function of the earth wire in an extra high voltage line is to?

The function of the earth wire in an extra high voltage line is to?

The function of the earth wire in an extra high voltage line is to provide a shield to the phase conductors from direct lightning stroke.

## Related questions

Description : The conductor of a 10 km long, single phase, two wire line are separated by a distance of 1.5 m. The diameter of each conductor is 1 cm, If the conductors are of copper, the inductance of the circuit is

Last Answer : The conductor of a 10 km long, single phase, two wire line are separated by a distance of 1.5 m. The diameter of each conductor is 1 cm, If the conductors are of copper, the inductance of the circuit is 23.8 mH.

Description : For a fixed value of complex power flow in a transmission line having a sending and voltage V, the real power loss will be proportional to  A) V B) v2 C) 1/V2 D)1/V

Last Answer : For a fixed value of complex power flow in a transmission line having a sending and voltage V, the real power loss will be proportional to 1/V2

Description : A voltage of 1000 kV is applied to an overhead line with its receiving end open. If the surge impedance of the line is 500 ohm, then the total surge power in the line ill

Last Answer : A voltage of 1000 kV is applied to an overhead line with its receiving end open. If the surge impedance of the line is 500 ohm, then the total surge power in the line ill 2000 MW .

Description : A 60 Hz, 320 km lossless line has Bending end voltage 1.0 p.u, The receiving end voltage on no load is?

Last Answer : A 60 Hz, 320 km lossless line has Bending end voltage 1.0 p.u, The receiving end voltage on no load is 1.088 p.u.

Description : To increase the visual critical voltage of cporona for an overhead line, one solid phase-conductor is replaced by a "bundle" of four smaller conductors per phase, having an aggregate cross- ... solid conductor is 40 mm, then the radius of each of the bundle conductors would be?

Last Answer : To increase the visual critical voltage of cporona for an overhead line, one solid phase-conductor is replaced by a "bundle" of four smaller conductors per phase, having an aggregate cross- ... conductor is 40 mm, then the radius of each of the bundle conductors would be 30 mm.

Description : A 100 km transmission line is designed for a nominal voltage of 132 kV and consists of one conductor per phase. The line reactance is 0.726 ohm/km. The static transmission capacity of the line, in MW, would be   (a) 240 (b) 132 (c) 416 (d) 720

Last Answer : A 100 km transmission line is designed for a nominal voltage of 132 kV and consists of one conductor per phase. The line reactance is 0.726 ohm/km. The static transmission capacity of the line, in MW, would be 240

Description : High Voltage DC (HVDC) transmission is mainly used for  (A) bulk power transmission over very long distances (C) inter-connecting two systems with same nominal frequency (C) eliminating reactive power requirement in the operation (D) minimizing harmonics at the converter stations

Last Answer : High Voltage DC (HVDC) transmission is mainly used for bulk power transmission over very long distances

Description : What is the function of a fuse wire? (a) To prevent an unduly high electric current from passing through a circuit (b) To increase the current supply (c) To decrease the current supply (d) To stabilise the voltage

Last Answer : Ans:(a)

Description : The rated voltage of a 3-phase power system is given as  A) rms phase voltage B) Peak phase voltage C) rms line to line voltage D) Peak line to line voltage

Last Answer : The rated voltage of a 3-phase power system is given as rms line to line voltage

Description : If a voltage-controlled bus is treated as load bus, then which one of the following limits would be violated?   (a) Active power (b) Reactive power (c) Voltage (d) Phase angle

Last Answer : If a voltage-controlled bus is treated as load bus, then which one of the following limits would be violated?   (a) Active power (b) Reactive power (c) Voltage (d) Phase angle

Description : A single phase transformer has resistance and reactance of 0.2 pu and 0.6 pu respectively. Its pu voltage regulation at 0.8 pf lagging would he

Last Answer : A single phase transformer has resistance and reactance of 0.2 pu and 0.6 pu respectively. Its pu voltage regulation at 0.8 pf lagging would he 0.52

Description : A transformer has negative voltage regulation when its load power factor is   (1) Zero (2) Unity (3) Leading (4) Lagging

Last Answer : 0

Description : An alternator has a phase sequence of RYB for its phase voltage. In case the direction of rotation of alternator is reversed, the phase sequence will become?

Last Answer : An alternator has a phase sequence of RYB for its phase voltage. In case the direction of rotation of alternator is reversed, the phase sequence will become RBY.

Description : The non-uniform distribution of voltage across the units in a string of suspension type insulators is due to?

Last Answer : The non-uniform distribution of voltage across the units in a string of type insulators is due to the existence of stray capacitance between the metallic junctions of the units and the tower body.

Description : The low voltage winding of a 400/230 V, 1-phase, 50 Hz transformer is to be connected to a 25 Hz, the supply voltage should be

Last Answer : The low voltage winding of a 400/230 V, 1-phase, 50 Hz transformer is to be connected to a 25 Hz, the supply voltage should be 115 V.

Description : With 100 % inductive shunt compensation, the voltage profile is flat for?

Last Answer : With 100 % inductive shunt compensation, the voltage profile is flat for zero loading of line.

Description : For certain geometry and operating voltage of the uncompensated transmission line, the ratio of power transfer capability to the surge impedance loading with an increase in length

Last Answer : For certain geometry and operating voltage of the uncompensated transmission line, the ratio of power transfer capability to the surge impedance loading with an increase in length decreases.

Description : In a string of suspension insulators, the voltage distribution across the different units of a string could be made uniform by the use of a grading ring, because it?

Last Answer : In a string of suspension insulators, the voltage distribution across the different units of a string could be made uniform by the use of a grading ring, because it forms capacitances which help to cancel the charging current from link pins.

Description : As compared to a 2-wire D.C. distributor, a 3-wire distributor with same maximum voltage to earth uses only (a) 31.25 percent of copper (b) 33.3 percent of copper (c) 66.7 percent of copper (d) 125 percent of copper

Last Answer : (a) 31.25 percent of copper

Description : The operating voltage of extra high tension cables is upto (a) 6.6 kV (b) 11 kV (c) 33 kV (d) 66 kV (e) 132 kV

Last Answer : (d) 66 kV

Description : cables are used for 132 kV lines. (a) High tension (b) Super tension (c) Extra high tension (d) Extra super voltage

Last Answer : (d) Extra super voltage

Description : In a 3-phase extra-high voltage cable, a metallic screen around each core insulation is provided to  (a) Facilitate heat dissipation (b) Give mechanical strength (c) Obtain longitudinal electric stress (d) Obtain radial electric stress

Last Answer : In a 3-phase extra-high voltage cable, a metallic screen around each core insulation is provided to Give mechanical strength

Description : What is meant by extra high voltage transmission?

Last Answer : HT & LT  two types transmission in industrial line

Description : The zero sequence current of a generator for line to ground fault is j 2.4 p.u. The current through the neutral during the fault is (a) j 0.8 p.u (b) j 2.4 p.u. (c) j 0.24 p.u. (d) j 7.2 p.u.

Last Answer : j7.2

Description : A 20-MVA, 6.6-kV, 3-phase alternator is connected to a 3-phase transmission line. The per unit positive-sequence, negative-sequence and zero-sequence impedances of the alternator are j0.1, j0.1 and j0.04 respectively. The neutral of ... the fault is  (A) 513.8 V (B) 889.9 V (C) 1112.0 V (D) 642.2 V

Last Answer : A 20-MVA, 6.6-kV, 3-phase alternator is connected to a 3-phase transmission line. The per unit positive-sequence, negative-sequence and zero-sequence impedances of the alternator are j0.1, ... line. The voltage of the alternator neutral with respect to ground during the fault is 642.2 V

Description : Choose two appropriate auxiliary components of a HVDC transmission system from the following P. D.C line inductor Q. A.C line inductor R. Reactive power sources S. Distance relays on D.C line T. Series capacitance on A.C. line  (A) P and Q (B) P and R (C) Q and S (D) S and T

Last Answer : Choose two appropriate auxiliary components of a HVDC transmission system from the following P. D.C line inductor Q. A.C line inductor R. Reactive power sources S. Distance relays on D.C line T. Series capacitance on A.C. line  (A) P and Q (B) P and R (C) Q and S (D) S and T

Description : A 800 kV transmission line is having per phase line inductance of 1.1 mH/km and per phase line capacitance of 11.68 nF/km. Ignoring the length of the line, its ideal power transfer capability in MW is (A) 1204 MW (B) 1504 MW (C) 2085 MW (D) 2606 MW

Last Answer : A 800 kV transmission line is having per phase line inductance of 1.1 mH/km and per phase line capacitance of 11.68 nF/km. Ignoring the length of the line, its ideal power transfer capability in MW is 2085 MW

Description : The transmission line distance protection relay having the property of being inherently directional is (A) impedance relay (B) MHO relay (C) OHM relay (D) reactance relay

Last Answer : The transmission line distance protection relay having the property of being inherently directional is MHO relay

Description : An 800 kV transmission line has a maximum power transfer capacity of P. If it is operated at 400 kV with the series reactance unchanged, the new maximum power transfer capacity is approximately (A) P (B) 2P (C) P / 2 (D) P / 4

Last Answer : An 800 kV transmission line has a maximum power transfer capacity of P. If it is operated at 400 kV with the series reactance unchanged, the new maximum power transfer capacity is approximately P / 4

Description : A generator is connected through a 20 MVA, 13.8/138 kV step down transformer, to a transmission line. At the receiving end of the line a load is supplied through a step down transformer of 10 MVA, 138/69 kV rating. A 0.72 ... load (in per unit) in generator will be (A) 36 (B) 1.44 (C) 0.72 (D) 0.18

Last Answer : A generator is connected through a 20 MVA, 13.8/138 kV step down transformer, to a transmission line. At the receiving end of the line a load is supplied through a step down transformer of 10 MVA, 138/ ... MVA and 69 kV in load circuit, the value of the load (in per unit) in generator will be 36

Description : An HVDC link consist of rectifier, inverter transmission line and other equipments. Which one of the following is true for this link ?  (A) The transmission line produces/ supplies ... ) Both the converters (rectifier and inverter) consume reactive power from the respective connected AC systems

Last Answer : An HVDC link consist of rectifier, inverter transmission line and other equipments. Which one of the following is true for this link ?  (A) The transmission line produces/ supplies ... ) Both the converters (rectifier and inverter) consume reactive power from the respective connected AC systems

Description : A loss less transmission line having Surge Impedance Loading (SIL) of 2280 MW is provided with a uniformly distributed series capacitive compensation of 30%. Then, SIL of the compensated transmission line will be (A) 1835 MW (B) 2280 MW (C) 2725 MW (D) 3257 MW

Last Answer : A loss less transmission line having Surge Impedance Loading (SIL) of 2280 MW is provided with a uniformly distributed series capacitive compensation of 30%. Then, SIL of the compensated transmission line will be 2280 MW

Description : For enhancing the power transmission in along EHV transmission line, the most preferred method is to connect a  (A) Series inductive compensator in the line (B) Shunt inductive compensator at the ... (C) Series capacitive compensator in the line (D) Shunt capacitive compensator at the sending end

Last Answer : For enhancing the power transmission in along EHV transmission line, the most preferred method is to connect a Series capacitive compensator in the line

Description : The concept of an electrically short, medium and long line is primarily based on the  A) Nominal voltage of the line B) Physical length of the line C) Wave length of the line D) Power transmitted over the line

Last Answer : The concept of an electrically short, medium and long line is primarily based on the  Physical length of the line

Description : Which of the two generalized constants of a transmission line are equal?  (a) B & C (B) A & B (c) A & D (D) B & D

Last Answer : Which of the two generalized constants of a transmission line are equal?  (a) B & C (B) A & B (c) A & D (D) B & D

Description : Shunt compensation in an EHV line is used to (A) Improve stability. (B) Improve the voltage profile. (C) Reduce the fault level. (D) Substitute for synchronous phase modifier.

Last Answer : Shunt compensation in an EHV line is used to Improve the voltage profile.

Description : If an unsymmetrical line to ground fault occurs at the secondary terminals of a delta/star, ungrounded transformer, then  (A) zero sequence currents are present on both sides of the transformer  (B) ... side  (D) zero sequence currents are present on the primary side but not on the secondary side

Last Answer : If an unsymmetrical line to ground fault occurs at the secondary terminals of a delta/star, ungrounded transformer, then zero sequence currents are absent on both sides of the transformer

Description : Series capacitive compensation in EHV transmission line is used to

Last Answer : To maintain voltage stability

Description : For a 500 Hz frequency excitation, a 50 km long power line will be modeled as

Last Answer : For a 500 Hz frequency excitation, a 50 km long power line will be modeled as long line

Description : The sending end and receiving end voltages of a three-phase transmission line are 10 kV/ph and 9.5 kV/ph, respectively. If the resistance drop is 150 V/ph and receiving end power factor is 0.8, the sending end power factor is (A) 0.745 lagging (B) 0.775 lagging (C) 0.8 lagging (D) 0.85 lagging

Last Answer : Vscos¢s-Vrcos¢r=IR

Description : The transmission line feeding power on either side of the main transmission line is called?

Last Answer : The transmission line feeding power on either side of the main transmission line is called Secondary transmission.

Description : 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?

Last Answer : 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 line voltage drop.

Description : A long overhead transmission line is terminated by its characteristic impedance. Under this operating condition, the ratio of the voltage to the current at different points along the line will?

Last Answer : A long overhead transmission line is terminated by its characteristic impedance. Under this operating condition, the ratio of the voltage to the current at different points along the line will progressively increase from the receiving end to the sending end.

Description : The time taken for a surge to travel a 600 km long overhead transmission line is?

Last Answer : The time taken for a surge to travel a 600 km long overhead transmission line is 0.002s.

Description : A loss less line terminated with its surge impedance has

Last Answer : A loss less line terminated with its surge impedance has flat voltage profile.

Description : For a long uncompensated line the limit to the line loading ill governed by?

Last Answer : For a long uncompensated line the limit to the line loading ill governed by stability limit.

Description : With 100 % series compensation of line.

Last Answer : the circuit is series resonant at power frequency and high transient current.

Description : If a line is 100 % series compensated it may result into series resonance at power frequency of?

Last Answer : If a line is 100 % series compensated it may result into series resonance at power frequency of 50 Hz.

Description : The X:R ratio of 220 kV line as compared to 400 kV line is?

Last Answer : The X:R ratio of 220 kV line as compared to 400 kV line is smaller.

Description : A lossless radial transmission line with surge impedance loading?

Last Answer : A lossless radial transmission line with surge impedance loading takes negative VAr at sending end and zero VAr at receiving end.