The advantage of cables over overhead transmission lines is a easy. Tunnel engineering objective type questions practice set 01 mcq tunnel. What are the maintenance procedures for underground. Underground power cable, distribution cable, overhead. Threeconductor cables are available up to 8kv, but the vast majority of underground extruded circuits use singleconductor cables. Transmission cables are often 35in 75125mm in diameter and may be installed directly buried or in, typically, 68in 152203mm plastic conduits with commercial installations up to 500kv. What is the purpose of bedding on the underground cables. If a cable of homogeneous insulation has a maximum stress of 10 kvmm, then the dielectric strength of insulation should be a 5 kvmm b 10 kvmm. It is classified in four parts dc power supply part,cable part,controlling part, display part. Underground system is more flexible than overhead system. Which of the following methods is used for laying of. The size of intra building optical fiber cables is typically 24 smf cable.
Diagnostic testing of underground cable systems cable diagnostic focused initiative doe award no. Optical fibers in the backbone shall be terminated using a pigtailedassembly that have. For higher voltages, 3 cored constructions become too bulky, and hence, even with some limitations we employ single cored cables. Multiple choice questions mcq on network theorem 1. The electrostatic stress in underground cables is same at the conductor and the sheath minimum at the. Multiple choice questions mcq on transmission and distribution for electrical engineering. Such cables are an alternative to overhead cables, which are several meters above the ground.
Under ground cables presention linkedin slideshare. Kirchhoff s current law states that a net current flow at the junction i. 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. Underground cable simple english wikipedia, the free. Mainly above 6 square mm cables are called power cables but it depends upon the use of a cable.
Downtown areas with many tall buildings usually have few or no cables above ground, this is mainly for aesthetic purposes. Which one of the following tunneling methods is used for laying underground sewers. Mcq on transmission and distribution for electrical. Most recently cables multiple choice questions and answers pdf. Following electrical engineering multiple choice objective type questions and answers will help you in bsnl jto, gate 2020 and ies 2020 examinations. Technical specification for underground power cables and. Underground cables are at installation more expensive than overhead lines and for this reason, ehv underground cables are rarely appropriate for an entire new alternating current ac power transmission project. Cables multiple choice questions and answers preparation for competition exams pdf 1. Mcq on cables for electrical engineering electricalnotes4u. It demonstrates the higher technology in developed countries for fire prevention and to make the power lines less susceptible to outages during. Underground cables are an additional tool in our box the legislative frameworks and planning practices which determine how the decision between underground cables and overhead lines is made, vary from country to country. Underground power cable, distribution cable, overhead transmission line, industrial cable and their accessories by shinji umeda 1, noboru ishii 1, noriaki horiguchi 1, makoto maeda 1, takumi yamaguchi 2, hideo tanaka 3, hiroshi niinobe 3, takehiko mizuno 3, satoru maruyama 3, kunio iwasaki 4, hiroyuki majima 5, shigekazu amanuma 6, hideki kamiyama 7, masaji tokita 8, shingo. The metallic screens assist in complete impregnation of the cable with the compound.
Beyond that, insulation required for the cable is too much. In this page you can learn various important underground cable multiple choice questions answers, mcq on underground cable and connector, short questions and answers on underground cable,sloved underground cable objective questions answers etc. Pdf designing underground cable systems to withstand. Rgi cable workshop understanding underground cables. They distribute electrical power or telecommunications. Designing underground cable systems to withstand steady state and transient voltages conference paper pdf available october 2006 with 1,783 reads how we measure reads. Dc power supply part consist of ac supply of 230v is stepdown using transformer, bridge. 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 corresponding size of conductor will be most economical. Electrical engineering objective questions mcq with answer free pdf download.
Electrical engineering objective questions mcq with answer. Tunnel engineering objective type questions practice set. 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. The material commonly used for sheaths of underground cables is a lead b rubber c copper d iron ans. The highvoltage underground cables used on the national grid system can be one of three types. Multiple choice questions mcq on cables for electrical engineering. The armouring consists of one or two layers of which wire or tape. If space permits, underground cables might often be laid out with each conductor group more widely spaced from the next, and space for a haul road down the middle, like this. The bridge used for measurement of insulation cables a. Underground cables are usually employed to deliver 3 phase power. Diagnostic testing of underground cable systems cable. An underground cable is a cable that is buried below the ground.
Cables mcqs for preparation of fpsc, nts, kppsc, ppsc, and other test. Underground cable multiple choice questions mcq and. Instead, guidelines should be established for the appropriate use of ugcs to balance the needs of economic stakeholders, local. This is proposed model of underground cable fault distance locator using microcontroller. Recommended post mcq on electromagnatism 1 mcq on battery 2 mcq on synchronous motor 1 electrical engineering interview questions. The underground cable can be 23 times more expensive than the overhead cable. The underground system cannot be operated above a 440 v b 11 kv c 33 kv d 66 kv. See here for the magnetic fields produced by underground cables and specifically the fields produced by these three different types. About 23% of these are power cables, 18% are electrical wires. Electrical cables mcq question is the important chapter for a electrical engineering and gate students. The magnetic field follows the same principles as before, but with a distinct peak from each group of conductors and dips between them. Introduction since the loads having the trends towards growing density.
Most recently cables multiple choice questions and answers pdf 31. Undergrounding is the replacement of overhead cables providing electrical power or telecommunications, with underground cables. Overhead cables are often replaced with underground cables. A voltage has been applied to the two electrodes, and a current is flowing. Multiple choice objective question on power system part 1. To protect the sheath from mechanical injury due to armouring. Double steel tape armouring is used particularly for. In this post provide you latest and updated 2018 electrical mcq objective questions with answer which are help for preparation all electrical engineering exams like gate, ies, jto, psus, rrb jeaen, rrb loco pilot and technicians, ssc je, dmrc, lmrc, isro and other state level engineering exams.
Mafijur rahman electrical and electronic engineer professional associates limited. In countries where the regulatory regime has a strong focus on cost efficiency underground solutions are often not used. Underground power cables high voltage underground cables 2 2 circuits 3000m 3x1x2000mm2 e. As the voltage level increases the cost of insulation is increased therefore the underground cable is restricted to low and medium voltages. The metallic screens increase the heat dissipating power of the cable. Mcq on transmission and distribution for electrical engineering. A wide variety of types of underground cables options are available to you, such as conductor material, type, and application. Transmission of power by ac cables is impossible beyond a. The diagram shows two copper plates that are immersed in a solution of water and copper sulphate.