Cable passing through fire rated walls will be sealed with fire barriers of approved type. Cable laying 1excavation of cable trench, 2sand bed laying, 3cable laying on sand bed, 4putting brick vertically on both sides of cable, 5again sand filling on cable area, 6horizontal. Simplify laying cable with cable in conduit youtube. This guide covers copper and aluminum conductors from no.
First one shows direct buried cable installation and the second one shows cable passing through duct mainly where road crossing comes. Insulation resistance of hv cable should be checked by using 5 kv megger after installation and before termination of cables and readings shall be. Kcs is realizing the construction of cable laying with high quality and high reliability by performing the followings. Temperature range the temperature range of the cable is of great importance for both the user and fitter. Jul 01, 20 laying of underground cables the reliability of underground cable network depends to a considerable extent upon proper laying. Wrong handling of cabals, such as damages due to wrong handlinglaying of cable also weakens the insulation of the cables. The silk and cotton threads are wrapped around the individual conductors in reverse directions. The 3 main underground cable laying system use in practice. In the urban areas, the power cable runs in undergrounds instead of overhead lines. The cable is fed from the bottom of the reel so that its curvature is continuous with no reversed bends.
Riser cables are generally required for vertical applications and plenum cables are required where there is a. Hvi has a great deal of experience in this area and already supplies many utilities with this equipment. Are the trench, shaft, cable duct or cable pipe free of foreign bodies, sharp edges or corners and dampness or moisture. All cable shall be securely fixed to the tray, work and the complete installation must be carried out in a neat and workmanlike manner without crossovers. High voltage xlpe cable systems techincal user guide brugg cables page 3 1. Documentation fibre optic installation guidelines conclusion 2. Cable preparation and pulling procedure best practices for. The procedure covers the details of hv and lv cable. Laying of underground cables the reliability of underground cable network depends to a considerable extent upon proper laying. Method statement for installation of high voltage hv cables.
With southwires sentry cableinconduit sentry cic, primary ud cable is preinstalled in a hdpe conduit, which allows for damage free onestep installations. Nov 03, 2015 cable laying cables for power transmission and distribution networks and cables for major communications networks within city areas are usually installed in trenches, directly buried in the ground. As per ceatechnical standards for construction of electrical plants and. Network systems cable fault locating 15 kv 35 kv cable. Exact minimum bending radii for specific cables can be found in the information sheets of the cable manufacturer. This method of laying underground cables is simple and cheap and is much favoured in modern practice. The problem with installation and manufacturing is that people often pursue the shortcuts to obtain the result.
Type of cable basedon construction coaxial cable mineralinsulated copperclad cable twinax cable flexible cables nonmetallic sheathed cable or nonmetallic building wire, nm, nm b1 metallic sheathed cable or armored cable, ac, or bx1 multicore cable consist of more than one. If cable tray system has been installed appropriately in a project, following advantages can be counted. Conditionbased maintenance this checks underground power transmission cables and aboveground grid fixtures like joints and terminations that have already experienced partial damage. Wrong handling of cabals, such as damages due to wrong handling laying of cable also weakens the insulation of the cables. Type of cable basedon construction coaxial cable mineralinsulated copperclad cable twinax cable flexible cables nonmetallic sheathed cable or nonmetallic building wire, nm, nm b1 metallic sheathed cable or armored cable, ac, or bx1. The trench is covered with a layer of fine sand of about 10 cm thickness and the cable is laid over this sand bed.
Ppt underground cables powerpoint presentation free to. The sand bed protects the cable from the moisture from the ground. The depth of burial should be enough to prevent damage caused by dragging anchors, which may be in excess of 15 feet for large ships on sandy bottoms. But over the time, the insulation of cable may get damaged or weakened due to ageing. Insulation resistance of hv cable should be checked by using 5 kv megger after installation and before termination of cables and readings shall be submitted to the consultant. Example of asbestos paper insulation wrap on highvoltage cable inside an underground cable vault.
The stepped up voltage is distributed to grid stations where it is stepped down for distribution to the local transformers where it is. Laying electrical cable underground is a project that a lot of people undertake at some point in their lives. The supplied length of cable is not sufficient to perform the intended job, e. Powerpoint slide on underground cable laying compiled by manish kumar jha. Cable laying shall be started by rotating the drum in a direction, recommended and marked side of the cable drum and cables are pulled, accordingly. There are three main methods of laying underground cables a. Method statement for installation of cable tray or trunking. It is better to follow the safety manual than to indulge yourself in jeopardy. Cable cables are supplied on cable drums as laying is done from cable drum into cable ditch. Figure f2 cable feed into conduit at floor level c from cable reel to cable tray, the cable is fed from the top of the reel to maintain required curvature. Ltht power cables, installation, jointing, termination, testing.
The procedure covers the details of hv and lv cable installation works in cable trays through the bridges. It can function as a waveguide, or light pipe, to transmit light between the two ends of the fibre. The cable should not be installed in environments exceeding its specified maximum and minimum installation temperature. To avoid possible damage from a sudden stop, the payoff must be equipped with a progressive braking system. Several layers of the soft and friable insulation are wrapped around the cable in long, wide strips. The system of cable laid with a serving and its enough to protect the power. Generally the bending radius of a cable is greater than 20d, where d is the diameter of cable. In premises applications, fiber optic cables can be used as the backbone cabling in a standard structured cabling network, connecting network hardware in the computer roommain cross connect. General information on high voltage cable systems 1. A free powerpoint ppt presentation displayed as a flash slide show on id. The aim is to lay down method statement for cable installation in safe manner to prevent any damage to cable, property or individual and ensure quality of work as per contract specifications and standards. Optical fibre cable jointing december 20 optical fibre cable jointing 1. The combination of the rope eye knot and proper cable grip device, along with an approved and rated shackle, make for a. Safe work procedure for cable pulling the quest for the self.
It helps to predict when and what kind of repairs might be needed in. Cable tray installation provides dependability in any circumstances. Then the trench is covered with a 10 cm thick layer of fine sand. A hv tdr test was performed on the cable the defect sites were located. Oct 27, 2018 cable laying 1excavation of cable trench, 2sand bed laying, 3 cable laying on sand bed, 4putting brick vertically on both sides of cable, 5again sand filling on cable area, 6horizontal. Before pulling the cable, to ensure of the stability of the payoff. Cable tray system saves space, materials, labor, time and cost. This procedure provides detailed for underground pipe installation in soil conditions as prevalent in the project area. Whenever the fault occurs in underground cable it is difficult to detect the exact location of. How to install concealed conduit electrical wiring system. Underground cable laying proposal to lay power cable and. Pilc, xlpe, epr this is a summary of the equipment hvi would recommend for cable fault locating on network systems and feeders rated up to 35 kv and of mixed insulation types. This drawing shows how to lay a low tension lt power cable, single core direct buried method. The trench also cover with bricks or concrete slab then again fill with soil.
Underground cable laying proposal to lay power cable and ofc in. Optical fibre cable ofc by laying both in one trench. The cable tray shall be installed with a 40mm minimum space between the structure and the tray. There are various hazards associated to this field. Cable laying method for road crossing and utility service crossing using upvc duct drawing below shows installation of underground cable in two environments. There are a lot of things that you have to take into consideration when doing this project. Optical submarine cable laying method laying procedure. Oct 30, 2017 there are various hazards associated to this field. Southwire companyspower cable installation guide provides installation information for extruded dielectric power cable systems. Lv cables are laid directly in ground and so its cheapest, simplest and extensively used method.
Cables must be buried in waters where marine traffic is present. Under ground cables presention linkedin slideshare. Then the laid cable is again covered with a layer of sand of about 10 cm thick. Installation method statement for cable tray ladder. Slab conduits for house wiring should be done in 2 mm thick 25 mm size fr pvc conduits. Introduction an optical fibre is a flexible, transparent fibre made of high quality extruded glass silica or plastic. The bottom of the trench should be smooth, undisturbed, welltamped earth or sand. The layout of this cable laying systems can show in the figure. The sand prevents the entry of moisture from the ground and. Cables on faceup horizontally fixed tray must be secured by use of the tie wraps where not in. May 19, 2017 cable tags will be installed on both ends of the cable. During final bending the cable can, therefore, be bent more tightly.
Electrical cable lugs crimping procedure for beginner. Linking of small exchanges off main road by leading in o. Cable laying cables for power transmission and distribution networks and cables for major communications networks within city areas are usually installed in. Installation, testing and jointing of lt and ht power cables up to. Table of cable components 12 metallic screens earthing shortcircuit operating conditions 14 grounding methods 14 earth cable protection 15 earthing diagrams 1617 laying methods 1819 cable reels 20 permissible bending radius 20 pulling tensions 20. Cable had failed in one phase in a splice and during the same failure the cable had a insulation failure on second phase.
Here are some tips to undergo a safe work procedure for cable pulling. Cable tags will be installed on both ends of the cable. Preferably slab conduits shall be laid in between top and bottom reinforcement. The direct system of cable laying involves the cables laid in a cable trench and after that, the cable is filled with soil. Minimum possible route length vis a vis route having maximum number of towns with potential telecom growth. All installed cables to be sealed at both ends by proper end caps shrouded to avoid dirt, debris and water accumulation. The type of installation proposed based on the site conditions and terrain in the project area is underground installation in trenches. If you do decide to do it by yourself, you will have. In this method of laying underground cables, a trench of about 15 metres deep and 45 cm wide is dug.
Exceeding the minimum bending radius of the cable can cause damage to the fibers, which cannot be seen from outer surface of the cable. This can also lead to expensive restoration of cables at later dates. High voltage xlpe cable systems technical user guide. The rope, on the other hand, requires a perfect eye knot. Scope of this method statement covers the following activities. The process involves stepping up the voltage to minimize the loss of energy in the form of heat. Cable failures cables damaged after installation a tap into an existing cable tee or wye splices. In addition to laying cables directly on the bottom, burying cable in a trench using the jetwater method should be considered. Prasad chartered engineer power point presentation on cable joints and terminations. Industrial underground power cable fault identification using. The purpose of work procedure for cable pulling generating this method statement is to define the procedure step by step to implement the correct practice for laying the cable from substation to the location of newly assigned area. All the cable trays and trunking covers shall be secured with proper clamps or screws fixed with supports.
It helps to predict when and what kind of repairs might be needed in the future, or if faulty sections need immediate replacement. The covering is then impregnated with a special wax compound. It does not legally have to be done by an electrician despite what some people may believe. Many have experienced the frustration of a power outage resulting from a failed. Cable lugs are ensuring the proper electrical contact between them. Tension during laying of the cable particular attention must be paid to the maximum possible tension.
Cable lugs are the electrical connector which used to connect the cables to electrical appliances. Silk and cotton insulation keeps the size of the cable small enough to be handled easily. If it is necessary to install any of these types of cable in an inair environment i. Cable laying work components like digging, trench forming, cable laying etc. Then the trench is covered with a 10 cm thick layer of. When electrical energy is generated in the generations stations, it is distributed to the different loads, i. A guideline for laying of cables and installation of sleeves.
This manual provides installation information for power and control cables for industrial. Record for future reference the cable identification markings, which consist of sheath number, footage, and cable description codes printed on the cable outer sheath. Cable tray system enhances safety of electrical wiring system. The combination of the rope eye knot and proper cable grip device, along with an approved and rated shackle, make for a typical ideal condition.
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