Underground installation of optical fiber cable by pulling. For same reasons, only lszhfr cables can be installed inside premises. Departures from this specification shall be fully documented in the tender. Temperature range the temperature range of the cable is of great importance for both the. These include tradeoff analysis between depth of installation, cost of installation, and thermal stabilization. Installation of undergroundsubmarine electric cables. The installations and maintenance of underground cables are far more expensive than overhead lines. This tests underground cables using lowenergy signals that do not cause insulation damage, making it possible to locate a faulty section. Osp cables may be installed by direct burial underground, pulled in underground ducts or conduit and mounted on poles in aerial installations. Underground cable installation manual western power.
Power cables are used for power transmission and distribution purpose. Ieee guide for the design and installation of cable systems in power generating stations ansiieee std 4221986 revision of ieee std 4221 977 published by the institute of electrical and electronics engineers, inc 345 east 47th street, new york, ny 10017, usa. Installation guide for optical fibre cable edition 05. This practice covers the basic guidelines for installation of fiberoptic cable in underground cable. Size and length of the cables to be checked by the engineer in charge and supervisor before cutting the hv cables. Any underground cables which are damaged during installation should be immediately repaired with equal quality material. Assessment of 69 kv underground cable thermal ratings. Cables installed into conduits or trays have installation parameters such as maximum pulling tensions, sidewall pressure, clearance, and jamming, which must be considered.
It is an assembly of one or more individually insulated electrical conductors, usually held together with an overall sheath. Insulating underground cables a typical cable installation method cables are laid in a trench in groups of three. Uo kv phasetoground voltage, u 225 kv rated phasetophase voltage, um 245 kv highest permissible voltage of the grid high voltage underground cables 6. Single phase underground service meter installation figure 9. The proposed cable will be installed in a steel pipe, which provides protection from accidental dig.
The purpose of undertaking underground cable testing is to prove cable integrity after installation and jointing work is completed and before connection to the essential energy network. Fiber optic cable is also placed underwater across rivers or lakes. The selection, handling and installation of electric power cables of rating not. The proposed cable will be installed in a steel pipe, which provides protection from accidental digins. Power cable installation guide cables installed into conduits or trays have installation parameters such as maximum pulling tensions, sidewall pressure, clearance, and jamming, which must be considered. Underground electric transmission lines wisconsin psc wi. Ausgrid maintains a copy of this and other network standards together with updates and amendments on. Section two covers all topics for correctly installing kerite cable, from selecting conduit and duct sizes, pulling tensions, minimum bending radius, proper cable support and field testing the installed cable. Current transformer cabinets, overhead or underground service, window type cts figure 11. Classification based upon number of conductors in the cable.
This is known as direct burial, and if you do this, the uf cable must be at least 24 inches below the surface of the ground, to minimize the chance of the cable being pierced by routine shoveling. Edit the specification and details to make them project specific. Other installations, such as buried and aerial, have different installation parameters. These limits should not be used for cables subjected to pulling tensions during installation. Increased care during installation and the use of modern cable insulation have resolved the historic.
A guideline for laying of cables and installation of sleeves. Fiber optic cable, underground installation, cable pulling. Installation of an underground transmission cable generally involves the following sequence of. Cable shall be installed between 750mm and 1200mm cover section 14. This method is normally used for installing heavier electrical cables.
Ns specification for laying undgerground cable up to. Premise cables these cables are designed to handle the stresses of indoor applications. Section two cable installation the cables ultimate life is optimized by taking proper care during installation. The range of recommended installation temperatures of cables is much smaller than the operating temperature ranges. Rockbolts and cables 6 30 minutes, the bolt can be tensioned within two or three minutes of installation after the fast anchor resin has set. Power cable installation guide figure f5 multiple sheaves figure f6 sheave arrangements for feeding into cable tray training radius the training radius is the final positioning of cable ends after the cable has been placed in the raceway. Power cables are mainly used in distribution networks of power utilities, in industries, in mines etc. Xlpe cable has become the national standard for underground electric transmission lines less than 200 kv. Welcome to the ninth edition of general cables cable installation manual for power and control cables. Typically, an underground cable has either one, three or four cores. Cables incorporating an armour layer have an extruded bedding of polyvinyl chloride pvc or zero halogen material lszh. An underground cable essentially consists of one or more conductors covered with suitable insulation and surrounded by a protecting cover. Further, the vertical runs where the cable descends into the ground at the house side and emerges up from the ground at the outbuilding. Underground cables can help power projects to transmit power past sensitive areas of human habitation and address the concerns of stakeholders.
Underground installation of optic fiber cable placing. The solid dielectric material replaces the pressurized liquid or gas of the pipetype cables. Standardisedcable installation depth to minimum cover of750 mm and maximum depth of 1500mm, section 14. All dielectric self supporting adss fiber optic cable. To select the cable it is necessary to consider whether the specific system and installation conditions and requirements can be. Single mobile home underground service alternate meter pedestal figure 10. The circuit installation also includes grounding boxes, screen earthing connection boxesand the related earthing and bonding cables.
Pdf new technique to install power cables into ducts. Commscope cables meet or exceed all telcordia gr409core and ansiicea 696 requirements, as well as gr20core requirements for crush resistance, impact resistance, flexing and twistbend. O possibility of damaging underground cables or other utilities. Cable installation manual for power and general cable. The cable should never be bent below its minimum bending radius. Underground commercial distribution ucd installation and. Each cable trench is a metre across and over a metre deep fillin must be well compacted to aid the removal of heat concrete cable covers prevent accidental damage to cables and electrocution cementbound sand the conductor is.
Nsp002 policy for the installation of distribution power. Industry best practices for radiating cable installation in tunnels in order to identify optimum locations for radiating cables, one must have an understanding of specific requirements for the network and how the radiating cable location impacts signal coverage. All optical fiber cables are sensitive to damage during shipping, handling, and installation. Environmental aspects of hvdc underground cables trench width in directly buried cables hvdc underground cables are typically installed in a circuit comprising 2 cables bipole installation.
Armor mechanical damage during installation and operation. The method enables the installation of continuous sections of power cables in one step into a duct up to 3. The installation process is influenced by local conditions, local climate, customers. With more than 14,000 km of cables, 30,000 terminations and 18,000 joints installed and commissioned since 1962, general cables silec underground cabling solutions are your best partner for the life of the entire cable system. Obtain consultants approval before cables are covered and trenches backfilled. In addition to the issues discussed above, there are several sitespecific issues that need to be taken into account when designing and implementing underground power cable installations. Installation of high voltage underground cables april 2018ver2mh the width of the working strip is dependent upon the the voltage of the underground cable, the number of cables and how many trenches are required. Some of the important parameters that need special attention during cable pulling installation are. All horizon power workers engaged in installing underground cables. Apart armouring of single core cables is provided by round aluminium wires, multicore cables will have galvanized round steel wires. The extra cost of underground installation includes the higher cost of the. Tdr results are displayed as a graph, and properly functioning cables send back a return signal in a known timeframe based on. Buried cable installation practices cables, energy system.
Keywords manholes, winches, sheaves, jetting method. The width of this temporary working area is invariably more than the width of the easement strip required by national grid, and may not necessarily be centred on the underground cable. Ei 020019 installation of underground cables lv to 2kv. Direct in the ground in trenches underground cables. Diagnostic testing of underground cable systems cable diagnostic focused initiative doe award no. This policy shall be used as the primary source of information for the installation of distribution power cables. Further, the vertical runs where the cable descends into the ground at the house side. The connection of the hvdc underground cable to the hvdc overhead line can be placed in a small transition yard.
This part of the specification deals with the material requirements, installation, testing and commissioning of medium and low voltage underground cables in. When cables are installed in a raceway, underground electrical duct or cable tray. These guidelines on fiber optic cables underground installation aim at avoiding any damage to existing underground infrastructure such as existing foc, sewage or water pipes, electrical cables or other telecommunications cables. Cabling for centralized fiber architecture and olans. Epub underground power cable distribution cable overhead. Underground network installation is more expensive than oh lines, since the cost of cables include cable charges along with road restoration charges which make the per unit coat of ug cabling system several times greater than overhead system. Backbone passive distribution network equipment figure 1. Underground cables are usually employed to deliver 3 phase power. All parties installing new underground distribution power cables and auxiliary cables for connection to the ompany s network shall follow the content of this document. Optical fiber cables are designed with a minimum bending radius. The major disadvantages associated with using underground power cables are the added cost of installation, increased environmental disruption and increased repair time due to underground cable failure. This manual provides installation information for power and control cables for industrial. Beyond that, insulation required for the cable is too much.
Most extruded cables are ac, but a very few are dc. Specification for installation of underground conduit systems revision date. Land issues underground cables and overhead lines have significantly different footprints through the countryside when completed. When editing the specification, turn on hidden text and follow the spec editor notes. During the delivery of the optical cable the offloading. Specification for installation of underground conduit systems. Laying uf underground feeder cable directly into the ground. Technical specification for underground power cables and. Figures 5 and 6 depict sample transition structure designs. An introduction to underground cable installation placing cables underground has traditionally been seen as a more costly solution than an overhead alternative, however lower cost production methods such as xlpe over lead or oil filled cables, improved technologies and installation methods and increased reliability means the cost differential. Construction of underground cables studyelectrical.
Installation of underground submarine electric cables. All cables shall be installed with approved identification bands at each end and over their entire length at 30mtr intervals. Cables installed in ground shall be laid in a single, horizontal layer spaced 450mm apart. This tension is then locked in by the latersetting grout cartridges and the resulting installation is a fully tensioned, fully grouted rockbolt. For long distance power transmission, the charging current.
In the following paper, we would like to suggest some of these areas for your consideration in. Installing underground electric cables involves several steps including conduit and manhole installation, cable pulling, and cable splicing. Although several types of underground cables are available, the type of cable to be used will depend upon the working voltage and service requirements in general, an underground cable must fulfill the following necessary requirements. The selection, handling and installation of electric power cables of rating not exceeding 33kv part 9. Placing cables underground has the added benefits of reducing transmission losses, aiding planning consent and reduced risk of service supply loss through extreme weather. For issue to all ausgrid and accredited service providers staff involved with the design and installation of underground cables and conduits, and is for reference by field, technical and engineering staff. Lines is more, so the voltage regulation is better in case of underground cables low voltage drop. Ppt underground cables powerpoint presentation free to. Underground cables are, of course, meant to be installed or laid under the ground. The reliability of underground cable network highly depends upon proper laying of cables, quality of cable joints and branch connections etc. While underground cables are more reliable than overhead, fault locating and repair can be much more difficult and costly than that of an. It may be increased at certain points, for example road, rail, river and canal crossings, to accommodate the more. It covers 600 volts through 46 kv insulated copper conductors, however, the cable installation manual is not.
For higher voltages, 3 cored constructions become too bulky, and hence, even with some limitations we employ single cored cables. Method statement for installation of high voltage hv. There are three main methods of laying underground cables, which are i direct laying, ii drawin system and iii. 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. The installation company responsible for laying the cables must heed the following parameters. This document refers to other horizon power documents to provide reference standards for underground cable installation work. It demonstrates the higher technology in developed countries for fire prevention and to make the power lines less susceptible to outages during. Diagnostic testing of underground cable systems cable.
Undergrounding high voltage electricity transmission lines. Industry best practices for radiating cable installation in. Installation of cables in ducts is a common practice today, for both telecommunications and energy transport, ranging from single optical fibres to energy cables of over 100 mm diameter, and a. Undergrounding is the replacement of overhead cables providing electrical power or telecommunications, with underground cables. Method statement for installation of high voltage hv cables. Installation of high voltage underground cables national grid. The company is an indirect, whollyowned subsidiary of fortis inc. Ieee guide for the design and installation of cable systems. The tenderer is also required to offer a recommendation for the two voltage classes of cable. Ns specification for laying underground cables up to and including 11kv amendment no 3. Thus, some mvu cables are more susceptible to the effects of voltage surges, such as lightning, that can lead to failure. Installation procedure for hv cables in tray the total cable route shall be inspected to ensure that the routing is complete, as per approved layout and it is coordinated with other services. Medium voltage underground cables 8 round the conductor it is necessar to provide insulation to prevent electrical short circuits in ediu voltage cables there are two main types of insulation material. These cables are of course, constructed accordingly.
The minimum bend radius of each cable is relative to the cable s diameter. The crosslinked polyethylene xlpe underground transmission line is often called solid dielectic cable. Use um master specification 260543, underground services for electrical systems as basis for design and specifying underground electrical and telecommunication pathway systems. Introduction optical fiber cables for telecommunication application have been installed in pipesducts for many years. This guide is generic yet contains sufficient specific information applicable for most installations of adss cable. Underground network installation is more expensive than oh lines, since the cost of cables include cable charges along with road restoration charges which. When installing a high voltage electrical underground cable, a temporary working strip is normally fenced off to permit the construction of the underground cable safely and efficiently.
For constructing transmission lines of the same distance at the identical voltage level, underground lines cost roughly 4 to 14 times more than overhead lines 1. Mvu cables that experience prolonged, wet conditions may have degraded insulation, based upon the insulation material. Clarified cable sealing, exposed cables and terminated cables requirements, section 14. Installation of underground cables lv to 2kv document number.
The tests specified within this procedure are the mandatory minimum requirements. Single mobile home underground service pressure treated post figure 9a. The minimum bend radius of each cable is relative to the cables diameter. Ieee guide for the design and installation of cable. Thermal performance of 69 kv underground cables by tong. Undergrounding high voltage electricity transmission. An introduction to high voltage direct current hvdc.
They also intend to insure that the installation of foc is done in accordance with telecommunication standards. Ieee guide for the design and installation of cable systems in power generating stations ansiieee std 4221986 revision of ieee std 4221 977 published by the institute of electrical and electronics engineers, inc 345 east 47th street, new york, ny 10017, usa april 4, 1986 sh10447 withdrawn. Underground cable installation manual western power underground cables on western powers distribution system the specifications, procedures,practices and instructions contained in theucim detail the technical requirements to be followed by service providers. The other utilities must maintain clearances as outlined in the nesc or by mutual agreement. O digging operation is separate from cable placement. For underground cables less than 345 kv, the connection from overhead to underground lines require the construction of a transition structure, also known as a riser. When installing a high voltage electrical underground cable, a temporary working strip is normally fenced off to permit the construction of the underground cable. Why underground power cable installations need soil thermal.
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