Description : The material commonly used for sheaths of underground cables is (a) lead (b) rubber (c) copper (d) iron
Last Answer : (a) lead
Description : Besides a method of trial and error, which of the following methods is employed for solution of network problems in interconnected system ? (a) Circulating current method (b) Thevenin's theorem (c) Superposition of currents (d) Direct application of Kirehhoffs laws (e) All of the above
Last Answer : (e) All of the above
Description : The underground system cannot be operated above (a) 440 V (b) 11 kV (c) 33 kV (d) 66 kV
Last Answer : (d) 66 kV
Description : By which of the following systems electric power may be transmitted ? (a) Overhead system (b) Underground system (c) Both (a) and (b) (d) None of the above
Last Answer : (c) Both (a) and (b)
Description : Most of the high voltage transmission lines in India are (a) underground (b) overhead (c) either of the above (d) none of the above
Last Answer : (b) overhead
Description : In congested areas where excavation is expensive and inconvenient 'draw in system' of laying of underground cables is often adopted. (a) Yes (b) No
Last Answer : (a) Yes
Description : The material generally used for armour of high voltage cables is (a) aluminium (b) steel (c) brass (d) copper
Last Answer : (b) steel
Description : The material commonly used for insulation in high voltage cables is (a) lead (b) paper (c) rubber (d) none of the above
Last Answer : (b) paper
Description : Multicore cables generally use (a) square conductors (b) circular conductors (c) rectangular conductors (d) sector-shaped conductors (e) none of the above
Last Answer : (d) sector-shaped conductors
Description : Due to which of the following reasons the cables should not be operated too hot ? (a) The oil may loose its viscosity and it may start drawing off from higher levels (b) Expansion of the ... instability may rise due to the rapid increase of dielectric losses with temperature (e) All of the above
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
Description : The operating voltage of supertension cables is up to (a) 3.3 kV (b) 6.6 kV (c) 11 kV (d) 33 kV
Last Answer : (d) 33 kV
Description : The operating voltage of high voltage cables is up to (a)l.lkV (b)3.3kV (c)6.6kV (d)llkV
Last Answer : (d)llkV
Description : State the four methods of laying of cable. State precautions while laying of underground cable in the situation : (i) Minimum clearance between cable and water pipe line when running in parallel. (ii) ... is to be laid in the same trench, what should be minimum spacing between two cables ?
Last Answer : (i) Minimum clearance between cable and water pipe line when running in parallel:- 0.5 mtr. (ii) Minimum clearance between cable and water pipe line when running in parallel:- 0.5 mtr ... should be minimum spacing between two cables :- Then minimum 30 cm spacing is provided between 2 cables
Description : Describe with sketches the process of laying of underground cables by the drawing in method.
Last Answer : OR Procedure: * A trench of minimum 60cm deep is made along with cable route. * Width of trench depends on number of conduits to be laid. * Separate pipes are ... enough to allow a person to enter into duct without difficulty. * Unarmored cables are used in this type.
Description : Which of the following D.C. distribution system is the simplest and lowest in first cost ? (a) Radial system (b) Ring system (c) Inter-connected system (d) None of the above
Last Answer : (a) Radial system
Description : Which of the following is the demerit of a 'constant voltage transmission system' ? (a) Increase of short-circuit current of the system (b) Availability of steady voltage at all loads at ... of carrying increased power for a given conductor size in case of long-distance heavy power transmission
Last Answer : (a) Increase of short-circuit current of the system
Description : Overhead system can be designed for operation up to (a) 11 kV (b) 33 kV (c) 66 kV (d) 400 kV
Last Answer : (c) 66 kV
Description : The minimum clearance between the ground and a 220 kV line is about (a) 4.3 m (b) 5.5 m (c) 7.0 m (d) 10.5 m
Last Answer : (c) 7.0 m
Description : In transmission lines the crossarms are made of (a) copper (b) wood (c) R.C.C. (d) steel
Last Answer : (d) steel
Description : Overhead lines generally use (a) copper conductors (b) all aluminium conductors (c) A.C.S.R. conductors (d) none of these
Last Answer : (c) A.C.S.R. conductors
Description : Distribution lines in India generally use (a) wooden poles (b) R.C.C. poles (c) steel towers (d) none of the above
Last Answer : (b) R.C.C. poles
Description : High voltage transmission lines use (a) suspension insulators (b) pin insulators (c) both (a) and (b) (d) none of the above
Last Answer : (a) suspension insulators
Description : The distributors for residential areas are (a) single phase (b) three-phase three wire (c) three-phase four wire (d) none of the above
Last Answer : (c) three-phase four wire
Description : The voltage of the single phase supply to residential consumers is (a) 110 V (b) 210 V (c) 230 V (d) 400 V
Last Answer : (c) 230 V
Description : A booster is a (a) series wound generator (b) shunt wound generator (c) synchronous generator (d) none of the above
Last Answer : (a) series wound generator
Description : The square root of the ratio of line impedance and shunt admittance is called the (a) surge impedance of the line (b) conductance of the line (c) regulation of the line (d) none of the above
Last Answer : (a) surge impedance of the line
Description : The phenomenon qf rise in voltage at the receiving end of the open-circuited or lightly loaded line is called the (a) Seeback effect (b) Ferranti effect (c) Raman effect (d) none of the above
Last Answer : (b) Ferranti effect
Description : 310 km line is considered as (a) a long line (b) a medium line (c) a short line (d) any of the above
Last Answer : (a) a long line
Description : Which of the following are the constants of the transmission lines ? (a) Resistance (b) Inductance (c) Capacitance (d) All of the above
Last Answer : (d) All of the above
Description : The corona is considerably affected by which of the following ? (a) Size of the conductor (b) Shape of the conductor (c) Surface condition of the conductor (d) All of the above
Description : The usual spans with R.C.C. poles are (a) 40—50 meters (b) 60—100 meters (c) 80—100 meters (d) 300—500 meters
Last Answer : (c) 80—100 meters
Description : Galvanised steel wire is generally used as (a) stay wire (b) earth wire (c) structural components (d) all of the above
Last Answer : (d) all of the above
Description : Which of the following materials is not used for transmission and distribution of electrical power ? (a) Copper (b) Aluminium (c) Steel (d) Tungsten
Last Answer : (d) Tungsten
Description : The wooden poles well impregnated with creosite oil or any preservative compound have life (a) from 2 to 5 years (b) 10 to 15 years (c) 25 to 30 years (d) 60 to 70 years
Last Answer : (c) 25 to 30 years
Description : If variable part of annual cost on account of interest and depreciation on the capital outlay is equal to the annual cost of electrical energy wasted in the conductors, the total annual cost will be minimum and the ... (b) Ohm's law (c) Kirchhoffs law (d) Faraday's law (e) none of the above
Last Answer : (a) Kelvin's law
Description : are the conductors, which connect the consumer's terminals to the distribution (a) Distributors (b) Service mains (c) Feeders (d) None of the above
Last Answer : (b) Service mains
Description : Draw and explain the construction of underground cables.
Last Answer : Underground cables: OR Explanation:- i) Core or conductor: * It function is carry current. * Cable may have single or more than single core conductor. * Conductor ... handling of cables. * It is similar to bedding & consists of fiborous material such as jute.
Description : State the procedure for laying / installation of underground cable.
Last Answer : 1) Direct laying Cable: or Trench laying method: Procedure: * For laying of a cable trench about 1.5m deep and 0.5m wide is made along the cable route. * A ... over. * Cables laid in this manner are usually plain lead covered because troughing affords good mechanical protection.
Description : Why cast aluminium tri-foil clamp is used in single core cables laying?
Last Answer : When three conductors are clamped together the fluxes around the conductors are get cancelled
Description : Underground cables are laid at sufficient depth (a) to minimise temperature stresses (b) to avoid being unearthed easily due to removal of soil (c) to minimise the effect of shocks and vibrations due to gassing vehicles, etc. (d) for all of the above reasons
Last Answer : (c) to minimise the effect of shocks and vibrations due to gassing vehicles, etc.
Description : The electrostatic stress in underground cables is (a) same at the conductor and the sheath (b) minimum at the conductor and maximum at the sheath (c) maximum at the conductor and minimum at the sheath (d) zero at the conductor as well as on the sheath (e) none of the above
Last Answer : (c) maximum at the conductor and minimum at the sheath
Description : ACSR (Aluminium Conductor Steel Reinforced) are used as (A) over head transmission lines. (B) super conductors. (C) fuse (D) underground cables.
Last Answer : (A) over head transmission lines.
Description : Radioactive solid nuclear wastes are disposed off by (A) High temperature incineration (B) Pathological incineration (C) Pyrolysis (D) Underground burial in concrete containers
Last Answer : (D) Underground burial in concrete containers
Description : Coalification means the (A) Process of conversion of lignite into anthracite (B) Underground gasification of coal (C) Complete combustion of coal (D) Direct hydrogenation of coa
Last Answer : (A) Process of conversion of lignite into anthracite
Description : Solid type cables are considered unreliable beyond 66 kV because (a) insulation may melt due to higher temperature (b) skin effect dominates on the conductor (c) of corona loss between conductor and sheath material (d) there is a danger of breakdown of insulation due to the presence of voids
Last Answer : (d) there is a danger of breakdown of insulation due to the presence of voids
Description : Which of the following is not Powder-Based RP system? a.Selective Laser Sintering (SLS) b.Solid Object Ultraviolet-Laser Printer (SOUP) c.Electron Beam Melting (EBM) d.Direct Metal Deposition (DMD)
Last Answer : b.Solid Object Ultraviolet-Laser Printer (SOUP)
Description : In direct cooled system using hydrogen both stator and rotor conductors are made (a) solid (b) hollow (c) perforated (d) any ofthe above
Last Answer : (b) hollow
Description : Would you buy a dining table made using innovative light weight construction methods if it had the same look, quality and feel as a solid wood table and cost less?
Last Answer : If it has the same look, feel and quality then what’s the difference? Weight? I guess having the same quality would also indicate that it is as sturdy too. No brainer…buy the cheaper one.