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DISCIPLINE REQUIREMENTS – ELECTRICAL INSTALLATIONS CONTENTS Page 1 Scope 4 2 Regulations 4 3 Technical Requirements as Specified by the Engineer 4 4 Definitions 4 5 Portable Electrical Appliances and tools 5 5.1 Earth Leakage Units 5 5.2 Flexible Cables and Cords 5 5.3 Power Supplied by the Company – See Special Conditions of Contract 5 6 Excavation of Cable Trenches and Installation of Cables in Trenches 6 6.1 Cable Routing and Clearance to Excavate 6 6.2 Location of Trench 6 6.3 Method of Excavation 6 6.4 Risk of Collapse to Sides of Excavations 6 6.5 Keeping Excavations Free of Water 6 6.6 Excavation Depth and Arrangement of Cables 6 For more information or to give feedback on this document, please contact M&T Risk and Assurance Tel 00 27 11 638 2815 Page 1 of 34 AA REQ 565005 DISCIPLINE REQUIREMENTS – ELECTRICAL INSTALLATIONS ISSUE 0 23 March 2011 TO ENSURE THAT YOU REFER TO THE MOST CURRENT VERSION OF THIS DOCUMENT, GO TO THESOURCE APPROVED COPYRIGHT

REQ 565005 Electrical Installations

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Electrical Installation Requirements

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Electrical Installations

AA REQ 565005DISCIPLINE REQUIREMENTS ELECTRICAL INSTALLATIONSISSUE 023 March 2011

TO ENSURE THAT YOU REFER TO THE MOST CURRENT VERSION OF THIS DOCUMENT, GO TO THESOURCEAPPROVEDCOPYRIGHT

AA REQ 565005DISCIPLINE REQUIREMENTS ELECTRICAL INSTALLATIONSISSUE 011 April 2011 COPYRIGHT

DISCIPLINE REQUIREMENTS ELECTRICAL INSTALLATIONS

CONTENTSPage1Scope42Regulations43Technical Requirements as Specified by the Engineer44Definitions45Portable Electrical Appliances and tools55.1Earth Leakage Units55.2Flexible Cables and Cords55.3Power Supplied by the Company See Special Conditions of Contract56Excavation of Cable Trenches and Installation of Cables in Trenches66.1Cable Routing and Clearance to Excavate66.2Location of Trench66.3Method of Excavation66.4Risk of Collapse to Sides of Excavations66.5Keeping Excavations Free of Water66.6Excavation Depth and Arrangement of Cables66.7Marking of Cable Routes, Cable Markers76.8Material Classification77Installation of Cables not in Trenches87.1Cables Crossing Roads87.2Cable in Tunnels87.3Cables in Ducts87.4Cables Passing Through Concrete Floors of Foundations87.5Cable Installation on Racks or Trays97.6General Cable Handling107.7Cable Joints107.8Terminations107.9Sealing of Cables117.10Labelling of Cables117.11Cable Glands (Unless Specified in the Bill of Quantities)118Installation of Equipment118.1Motor Control Centres118.2LV Motors128.3MV Switchboards128.4Mini Substations128.5Distribution Transformers128.6General138.7Light Fittings138.8Light Fittings and Socket Outlets in Substations and Control Rooms148.9Protection of Equipment After Erection149Earthing149.1Substations149.2Cables159.3Welding Machines159.4General169.5Lightning Protection1610Conduit1610.1General1610.2Surface Conduit Installations1711Welding1711.1General1711.2Electrodes1811.3Corrosion Protection, Painting & Patching1812Method of Fixing Rack and Other Support Steelwork1812.1Welding1812.2Use of Hilti Studs1812.3Bolts, Nuts and Washers1812.4Unistrut1812.5Holes Drilled in Structural Steel1813Testing and Energising1913.1General1913.2Specific Tests Required1913.3Pressure Testing of MV Cables1913.4LV Cables (Up to 1kV)1913.5MV Switchgear2013.6LV Distribution Switchgear and Motor Control Gear2013.7Transformers2013.8Field Equipment2013.9Test Equipment2113.10Tests on Equipment Using Test Voltages Exceeding 1kV2113.11Test Certificates2113.12Checking the Completed Installation2113.13Commissioning and Energising of Equipment2214Acceptance of Work22Appendix A: Referenced documents23Appendix B: Record of Amendments23Appendix C: Site Test Certificate - Motors24APPENDIX D: SITE TEST CERTIFICATE - MOTOR CONTROL CENTRES25APPENDIX E: SITE TEST CERTIFICATE TRANSFORMERS26

ScopeThis document covers the Electrical Installations in Surface Plants excluding Overhead Lines and should be read in conjunction with the Bill of Quantities or the Contractors Scope of Work.It defines the standards of materials and equipment, installation work and ancillary work to be employed in the electrical installation contract or sub contract.

RegulationsAll Installations shall comply with the relevant sections of the following:Minerals Act and Regulations applicable to region.Occupational Safety and Health Act or equivalent regulations applicable to region.

Technical Requirements as Specified by the EngineerIEC 62305-3:The protection of structures against Lightning

IEC 62305-5-54:The design and installation of Earth Electrodes.

IEC 62305-1:The protection of Dwelling Houses against Lightning.

IEC 60364:Low Voltage Electrical Installations

Definitions

QAR:Quality Assurance Authority; An independent inspection agency appointed and approved by the Engineer

IEC:International Electro-technical Commission

Non- metallic enclosures/ polycarbonate enclosures:An enclosure or housing made from any non-metallic substance such as Polycarbonate, PVC, glass fibre, reinforced plastic (GRP), or others which are ultra-violet light resistant, corrosion resistant, impact resistant and deemed to be suitable for the duty envisaged.

Hazardous areas:Any Hazardous area classification on the Plant or works shall be specified to the Contractor in writing, or specified in the Bill of Quantities or the Contractors Scope of Work.

Stainless steel:Unless otherwise indicated the term stainless steel will mean grade 316 stainless steel.

XPLE:Cross Linked Polyethylene

The following terms are defined in the Conditions of Contract: Anglo American, Approved, Company, Contractor, Engineer.

Portable Electrical Appliances and tools

Earth Leakage UnitsAll electrical appliances and tools, working off 110 or 230 volt supply, shall be protected by an earth leakage unit of 30 milliamp sensitivity, either of a portable or fixed type.All 400 Volt feeders for portable equipment shall be protected by an instantaneous operating earth leakage unit of not greater than 250 milliamp sensitivity.Note: Welding Socket Outlets to be equipped with a separate circuit breaker c/w 30mA earth leakage unit for personnel protection.

Flexible Cables and CordsAll flexible cables and cords must have a separate continuous earth core.No joints are allowed in these cables.All cables must be fitted with an approved plug, suitably rated.The termination of cables on plugs must be done by a qualified electrician.Damaged plugs, cords or cables are not to be used.The user of cables or cords is held responsible to report any damage or noticeable defect to the Foreman electrician concerned.Repairs to electrical cords, cables and plugs may only be done by a qualified electrician.Note: when double insulated portable tools are used, clause 5.2 bullet 1 does not apply.All electrical tools where possible shall be of the double insulated type and must be to the approval of the Engineer.

Power Supplied by the Company See Special Conditions of ContractWhere the company supplies the contractor with power the contractor must report to the Engineer prior to commencing work on the Plant.The Engineer will arrange point/s of supply and inspection of the contractor's equipment.Note: the engineer reserves the right to discontinue power supply if in his opinion any equipment is unsafe or does not meet the conditions stipulated in this specification.

Excavation of Cable Trenches and Installation of Cables in Trenches

Cable Routing and Clearance to ExcavateNo excavation is to be commenced in an existing installation until authorisation has been given by the Engineer who will provide the Contractor with details of existing buried services in the area concerned.No installation should commence until such confirmation of the route has been obtained from the Engineer.Where obstructions are encountered which necessitate diversions of cables due to adjacent structures, pipes, drains, etc. approval of such deviations shall be obtained from the Engineer.The runs shall be selected to avoid exposure to drip or accumulation of liquids or high temperatures.

Location of TrenchThe exact location of each trench is to be approved by the Engineer.

Method of ExcavationThe use of mechanical excavation machines will only be permitted when written approval has been given to this effect by the Engineer.

Risk of Collapse to Sides of ExcavationsAny trench of a greater depth than 1.5 metres, or where ground conditions require, is to have the side walls adequately shored up.All precautions are to be taken to ensure that damage resulting from subsidence will not occur adjacent to roads, railways, walls, sewers, drains, pipes or similar structures.

Keeping Excavations Free of WaterThe excavations shall be protected from flooding, and any water which occurs in the excavations whether as a result of seepage, rain or other causes shall immediately be removed by baling, pumping or other approved method, ensuring that damage does not occur to cables.

Excavation Depth and Arrangement of CablesDepth of Cable TrenchesMinimum 600mm for low voltage cables and 900mm for medium voltage cables.

Width of Cable TrenchesThe minimum width of the trench to be 500mm.Trenching ConfigurationTrenches are to be straight, cut square and the bottom of a trench is to be level and free from stones or hard projections.The bottom of the trench is to be covered by a layer of fine sifted soil, at least 50mm thick, before any cables are laid. Laying of Cables in TrenchesCables shall be laid such that a minimum gap of 25mm is maintained between the outside edges of all cables. Covering In of CablesCables shall be covered with a layer of fine stone-free soil not less than 75mm thick. Thereafter the following procedure is to be followed:Medium and low voltage cablesThe trench is to be filled in with local soil. The soil is to be firmly stamped down. Any surplus soil is to be piled on top of the trench. One month later, any subsidence must be made good and the trench levelled off.

Marking of Cable Routes, Cable MarkersA PVC cable warning marker tape is to be installed in each trench running the complete length of the trench and be laid 300mm above the cables.Concrete cable markers are to be placed at a maximum of 50 metre spacings along the entire length of the cable trench/route and at every change in direction of the cable.

Material ClassificationThe removal and disposal of all materials encountered while carrying out excavation shall be included in one of the classifications of excavation as described in the Bill of Quantities or the Contractors Scope of Work.The decision of the Engineer as to the classification of the material shall be final and binding, and any objections as to the classification must be made in writing before the excavations have been backfilled.

Installation of Cables not in Trenches

Cables Crossing RoadsCables are to cross roads via one of the following methods, as indicated on the drawings:Cable tunnels with reinforced roofs and sturdy wallsCulverts, where the cables are in ducts.Culverts or reinforced concrete pipes with a minimum diameter of 150mm where cables are laid directly into the ground.NOTE: Where reinforced concrete pipes are used, a separate pipe is to be used for each individual cable having a bitumen jute serving (outer sheath).Suitable pipe sleeves made from steel or PVC with a minimum diameter of 110mm.NOTE: The Engineer will specify the number of cables per sleeve.On large diameter cables, only one per sleeve will be allowed.Analogue and telephone cables are to be in sleeves separate to electrical cables.After cables have been installed, each sleeve is to be sealed with a suitable material approved by the Engineer.

Cable in TunnelsCables shall be installed on racks along the sidewalls of the cable tunnel.

Cables in DuctsCables are to be neatly laid parallel to each other. The position of high, medium and low voltage cables is to be approved by the Engineer.Entrance of cables into the duct from the side shall be through a sleeve of adequate size (inside diameter of the sleeve is to be at least twice the outside diameter of the cable).After the cable has been installed, the sleeve is to be sealed with a suitable material approved by the Engineer.

Cables Passing Through Concrete Floors of FoundationsWhere cables pass through a concrete floor or foundation, etc., they will be passed through galvanised steel or high density PVC pipe that is at least 50mm larger than the cable diameter.In the case of floors, this pipe will extend from 60mm below to 360mm above the slab.NOTE: Not more than one long radius bend of up to 90 degrees may be used in any unbroken pipeline.The maximum overall length of such pipe section is not to exceed 30 metres. The minimum radius of a 90 degree bend shall be 15 times the cable outside diameter.

Cable Installation on Racks or TraysWherever possible, racks are to be mounted in the vertical plane.Racks to be adequately supported to carry the overall weight of the maximum number of cables for which such rack is designed.Racks are to be supported at every point where the route of the rack changes direction.Single angle iron cable supports may be used under the following conditions:not more than 2 cables per single angle ironthe angle iron shall be of adequate dimensions to support and protect the cable/sWhere cables are exposed and mechanical protection is warranted, a solid sheet metal cover shall be bolted into position. Power and control cables may be run on a common rack, providing they are separated and/or identifiable to the approval of the Engineer.Cables are to be clamped or strapped in separate voltage groups.A maximum of three cables may be bulk clamped or strapped providing they are of similar diameter.Spacing of cable clamps on cable racks must not exceed:OVERALL CABLE DIA. mm.MAX.SPACING - HORIZONTALMAX.SPACING -VERTICAL

Not exceeding 15mm.350mm450mm

15 - 22mm400mm525mm

22 - 32mm450mm600mm

Exceeding 32mm500mm700mm

NOTE: Vertical in the above table means a cable rack rising at 90 degrees to the horizontal.Horizontal means a rack running in the horizontal plane, with the rack mounted such that it is vertical or edgewise.Individual cables may be installed in galvanised conduit secured with saddles. Spacing shall be such as to maintain the cable in a straight line.Cable strapsUV stabilised PVC straps will be allowed. Heavier cables (> 25mm 4 core) will be strapped using stainless steel straps.

General Cable HandlingCables are to be laid in trenches or fixed on racks directly off the drum.Cables of long lengths shall be pulled with a cable stocking or pulling eye and pulled over cable rollers and corner rollers.Under no circumstances shall cable be pulled whilst in contact with the ground.In pulling cables, the manufacturer's specifications regarding the pulling force, bending radius etc. shall be observed. Suitable drum jacks are to be provided.Cables are to be transported around site on the cable drums provided by the cable manufacturer and on a custom built cable drum trailer and haulage vehicle.

Cable JointsType of joints to be used on:1. Low voltage cables (up to 1kV)Approved standard stock, cast type joint boxes or moulded resin joints are to be used.The armouring to be carried through externally on cast joint boxes and internally with moulded resin joints.1. MV Cables above 1kV not exceeding 52kVOnly appropriate approved jointing kits shall be used.1. ConnectionsAll cables are to be hexagonal crimped.1. PhasingColour-to-colour or number-to-number connections must be maintained throughout the length of cables.

TerminationsWhere cable cores are connected to stud type terminals, crimp-on lugs are to be used. Only appropriate approved medium voltage stud type connection insulation to be used for type C bushings, and where applicable, only appropriate approved putty to be used.M V Cable TerminationsOnly appropriate approved termination kits to be used on MV cables.Mini-substations, Transformer M.V. terminal boxes and MV SwitchgearOnly appropriate approved heat shrink-terminations to be used for crutch and cable tails in the terminal boxes of these units such as Raychem, Sigmaform, or 3M unless other terminating systems e.g. "DYSCON" or similar are being used.

Sealing of CablesCable ends shall be sealed immediately they have been cut. A lead seal end cap or PVC `heat shrink' end cap may be used.

Labelling of CablesAll cable cores shall be fitted with the correct marking ferrules as detailed on cable schedule and inter-connection diagrams.Every cable shall have a stainless steel "DYMO" type tape attached on each end on which shall be punched the cable number shown on the cable schedule.NOTE: As built cable schedules are part of the Special Conditions of Contract.

Cable Glands (Unless Specified in the Bill of Quantities)Indoor Areas, MCC Rooms and SubstationsOnly appropriate approved cable glands shall be used.Outdoor AreasOnly appropriate approved anti-corrosion type cable glands shall be used such as CCG corrosion guard type - no shroud.Hazardous AreasGlands to be used in such areas will be specified in the Bill of Quantities or the Contractors Scope of Work.

Installation of Equipment

Motor Control CentresMCC's are to be installed by the contractor only if specified in the Bill of Quantities or the Contractors Scope of Work.The tiers are to be handled with care and installed in the correct sequence as shown on the General Arrangement drawings.Any damage to the doors or equipment on the MCC's is to be reported to the Engineer as soon as possible.

MCC's will be tested in accordance with the Site Certificate - Motor Control Centres, attached to this specification. See also paragraph 13.6.Warning notices must be erected on energised circuits during commissioning.All wires connected to terminals must have enough slack to allow for remaking the terminations.

LV MotorsLV motors will be installed by others, but the contractor shall make the electrical connections. Cables are to be connected to the terminal box via a specified or approved gland. Motors to which 4 core cables are being used will have the 4th core terminated to the earth inside the terminal box. Where a separate external earth conductor is being used this will be bolted externally to the motor frame. All connections shall be made with compression lugs. Cable boxes on motors are to be drilled for cable entries and no burning of holes will be permitted.LV Motors will be tested in accordance with the Site Certificate - Motors, attached to this specification.

MV SwitchboardsNormally the manufacturer of any MV switchboards will install them.In certain circumstances, the Installation Contractor may be requested to install this equipment. This will be set out in the Contractors Scope of Work.Under no circumstances shall any MV switchboard be energised by the contractor without the permission of the Engineer and the approved inspection and test report by the manufacturer or representative.The installation shall comply with the appropriate Code of Practice and Testing Code of Practice.

Mini SubstationsAre to be installed complete including connecting MV and LV cable with specified termination kits and glands, neutral bushing to earth, transformer body to earth, auxiliary wiring to protective devices, neutral to earth CT for earth leakage protection, and installing dehydrating breather and padlock to transformer bay and warning boards when the transformer is energised.

Distribution TransformersAre to be installed complete including connecting MV and LV cable with specified termination kits and glands, neutral bushing to earth, transformer body to earth, auxiliary wiring to protective devices, neutral to earth CT for earth leakage protection, and installing dehydrating breather and padlock to transformer bay and warning boards when the transformer is energised. A thorough check shall be carried out by the Contractor to ensure all associated loosely transported parts of equipment has been installed ie. breather, conservator etc. An oil sample shall be taken and sent for testing for any ingress of moisture, if requested by the Engineer.

GeneralAll equipment shall be installed as per the manufacturer's instructions and to the approval of the Engineer.All equipment shall be carefully levelled and adjusted for operation.Precautions shall be taken to counter vibrations likely to be transmitted by plant machinery. As vibrations are unlikely to be fully evident until machinery is operating, checks for vibrations shall be made during commissioning.Any unsatisfactory conditions detected shall be reported in writing to the Engineer for remedial action.Equipment shall not be grouted in position prior to inspection and approval by the Engineer.Neither compressed air nor cotton waste shall be used for cleaning purposes.Distribution boards and control boards which are wall mounted shall have horizontal centre lines approximately 1 500mm above floor level.All equipment is to be protected throughout erection against the ingress of moisture, dust, dirt and foreign bodies.Equipment to be stored shall be given adequate covering. The contractor shall be responsible for any damage or loss of goods handed over to him and he will be required to replace, free of charge, any damaged or lost items.Light switches, socket, power and plug outlets shall be installed as indicated on the relevant drawings. Where it is not practical to mount the equipment as shown, amended instructions will be issued by the Engineer.Mounting heights of all other equipment will depend on the circumstances but will also be subject to the written approval of the Engineer.Multi-phase outlets shall be connected in accordance with the plant's standard rotation.Bare earth wires shall have a Heat Shrink covering at the terminals.A clearance of 2m or better shall be left between switches or socket outlets and water taps.

Light FittingsAll light fittings shall be installed in accordance with project drawings. However, due care and attention should be given to accessibility for maintenance and lamp replacement. All fittings shall be complete with lamp of correct size and type.Floodlights shall be orientated at night and then securely clamped, to ensure a uniform distribution of light over the area to be illuminated.Where suitable terminals are not provided within fittings the contractor shall provide suitable connectors.In general, all fittings should be fixed directly onto steelwork by means of suitable support brackets. The design to be approved by the Engineer if not detailed in the project drawings.Light fittings to have a minimum 3 way junction box associated with each. Connection to fitting, if suspended, to be flexible. Any unused gland holes to be fitted with stoppers. The Contractor must take particular care that the I.P. rating of any fitting is maintained during installation.Fittings installed in Hazardous Areas will have the correctly specified Cable Glands, and the contractor must ensure that the manufacturer's installation instructions are adhered to.The Engineer shall be notified in writing of the date on which lighting circuits are energised and the fittings in a particular plant area are put into service. The fitting and lamp guarantee period shall commence from this date. This date shall be recorded in writing by the contractor and agreed by the Engineer. This date will not necessarily be deemed to be a hand-over.

Light Fittings and Socket Outlets in Substations and Control RoomsWhen the Installation Contractor is requested to install lighting and socket outlets in substations and Control Rooms, the Contractor is to obtain from the Engineer an indication of the standard that will be required. This will normally be via drawings.These will indicate whether surface mounted conduit with wiring will be required, and specify whether PVC or metal conduit is to be used, as well as the colour in the case of PVC conduit.The Contractor may be required to phase the fittings.These items are to be agreed before the work is commenced.

Protection of Equipment after ErectionIt will be the responsibility of the contractor to ensure that all equipment erected by him is protected against accidental damage that could be caused by other ongoing erection activities of all disciplines.The contractor will therefore be called upon, to make good and damage caused to equipment due to lack of adequate precautions being taken, as described above with any costs being for his account.

Earthing

SubstationsStandard details will normally be shown on drawings and may include the following:Earthing rods or an earthing mat is to be installed as per the design drawings.

Branch tee-offs from the main earthing conductor to the earth mats, transformer star points and bonding of equipment are to be:brazed in the case of solid to solid conductor connectionsonly appropriate approved methods shall be used in the case of stranded to solid conductor connections such as exothermic welds, PG clamps or lugsAll cable trays, racking, conduit, trunking, cable sheaths and armouring, substation screens and all other metal work connected with wiring (other than the current carrying parts) are to be bonded to earth.The Contractor is to ensure that a suitable earth is provided. This shall be by use of a suitable specification, or notification that an earthing specialist is to be used.Overall impedance of less than 5 ohms to the general mass of earth should be obtained.

Cablesa) Armoured cables (LV below 1000V)The armouring is to be bonded to earth using mechanical compression glands to clamp the armouring at each end of the cable.NOTE. Single core armoured cables will have the armouring bonded to earth at one side of the cable only. This will normally be done at the sending end. b) Cables and motors and other up to 1kV equipmentMotors that have 4 core cables with the 4th core being used for earthing, shall in addition have the armouring made off in the usual manner.In this case the earthed core shall always be the "black" conductor. c) MV cables (XLPE)Armouring is to be made off in normal manner using suitable gland. Separate 70mm green PVC sheathed conductor from substation or switchgear earth bar to the item of equipment is to be installed in addition.

Welding MachinesThe earth leads of all welding machines must be of equal length to the electrode lead.The earth lead must be clamped directly to the material being welded.Proper joint couplers must be used for joints in welding leads. No joint consisting of lugs, bolted together and taped-up are permitted.1kV primary cable to be of the flexible trailing cable type, with each phase core individually screened.

GeneralFor 3 phase 3 wire installations where 4 core cable has been specified, the fourth core (black) shall be used as the earth conductor.On 3 phase 4 wire installations, the fourth core (black) shall be used as the neutral conductor with a separate suitably rated bare copper conductor used as the earth conductor.NOTE: in certain cases green PVC sheathed conductor may be specified as the earth conductor.NOTE: Bare earth conductors buried in the ground shall be kept at least 600mm from buried cables unless the cables are PVC sheathed overall. Insulated earth conductors are recommended where stray D.C. traction currents or soil conditions could cause electrolytic corrosion.All steel structures shall be bonded and earthed against static charges, in accordance with the drawings.Main earthing points shall be made of a suitable number of copper earth rods, driven to a suitable depth. Earth mats or plates shall be as specified by the Engineer.When the armour of a cable is earthed, the clamp used shall be of special design so that it will grip firmly and permanently without damage to the insulation or to the sheath of the cable.Where an earthing conductor is exposed to possible mechanical damage, it shall be protected by means of a suitable conduit or pipe, preferably non-metallic.Where earthing is carried out in acidic areas, all earth conductors shall be PVC insulated. The neutral point of all lighting transformers shall be earthed directly to the earth system by means of insulated conductors of the same cross sectional areas as the power cable.

Lightning ProtectionBuildings and metal structuresTo provide for lightning protection the contractor will install earth electrodes at the corners of buildings and metal structures. All structures must be so earthed at 2 opposite corners and at intervals of not more than 50 metres. The steel cladding and metal structures are then bonded to the earth electrode unless otherwise detailed on drawings.All down conductors installed within touching distance of personnel, shall be insulated to prevent accidental electrical shock.

Conduit

GeneralThe conduit shall have a minimum diameter of 20mm and be cut square and clean before threading. Threads shall be made using suitable conduit thread dies and the liberal application of cutting grease or similar. The length of thread shall be such as to permit conduits to be firmly butted together in couplings and hard against the shoulders of threaded conduit box spouts with no thread exposed.The ends of all cut lengths of conduit shall be reamed free from burrs and any loose swarf shall be removed from inside the conduit.Sockets, bends and fittings shall be of the same material as the conduit.

Surface Conduit InstallationsAll surface run conduits shall be of the galvanised type unless otherwise specified in the Bill of Quantities or the Contractors Scope of Work. Conduit runs on the surface of walls, floors, ceilings, or in accessible ceiling voids, etc., shall be installed in a neat manner running generally with the building lines. The conduits shall be vertically plumb and horizontally level as applicable. Bends in multiple runs of conduit shall be matching. Other right angle bends shall be standard machine made. In all instances the installation shall present a neat and workmanlike appearance.Where open-ended conduit is used to support lighting cables, the ends shall be bushed.Fixings of tubing shall be affected by spacer bar saddles. Light gauge saddles may be used for general internal installations whilst heavy base saddles are to be used for external galvanised conduit installations and industrial applications.

Welding

GeneralWelding shall comply with the requirements of IEC 60050-851, Welding.Before any welding is carried out on an existing structure, the properties of the steel shall be determined.All welding shall be done by qualified welders who have been previously qualified by test in accordance with the requirements of IEC 60050-851 - Welding and the contractor shall submit evidence of such qualifications to the Engineer if called upon to do so. An operator shall require re-qualification if he has not been engaged in metal welding for a period of three months or more, or when changing type of material, or if there is a specific reason to question the welder's ability.All welding shall be by the electric arc process unless oxyacetylene welding is specified.The welding plant return clamp is to be at all times connected directly to the item being welded, to prevent damage to any equipment by stray return currents.The Engineer may direct the contractor to remove any inferior welding and/or direct the contractor to cut test specimens from the welds which, in the Engineer's opinion, are of inferior quality. The Engineer may direct that welds be nick broken or bent in his presence. Alternatively the contractor may provide x-ray or other approved non-destructive tests on suspect welds with all test methods being subject to the prior approval of the Engineer.

ElectrodesElectrodes shall be selected so that the resulting weld is compatible with the design requirements with respect to both strength and ductability.

Corrosion Protection, Painting & PatchingRefer to specification issued for the Project in the Bill of Quantities or the Contractors Scope of Work.

Method of Fixing Rack and Other Support Steelwork

WeldingWhen welding as a method of fixing rack and support brackets and steelwork onto existing steelwork is prohibited, this shall be indicated to the Contractor in the Scope of Work. In such cases, all support steelwork requires to be attached to existing steelwork using the drill and bolt method.When welding as a method of fixing rack is allowed, the Contractor shall ensure that the specifications for priming, patching, and painting of steelwork, and any other corrosion control prevention methods required, are properly executed.

Use of Hilti StudsThis type of fixing may be permitted when welding is not allowed.The contractor will be required to enforce all the necessary safety precautions that are required by the Engineer and as laid down by the Minerals Act or the OSH Act applicable to region.

Bolts, Nuts and WashersSpecified areas are to be stainless steel.Non-specified areas to be galvanised.

UnistrutAll Unistrut to be hot dip galvanised No stainless steel need be used

Holes Drilled in Structural SteelNo holes shall be drilled without approval of the Structural Engineer. Any holes drilled are to be made good as detailed in the Painting and Corrosion Specification.

Testing and Energising

GeneralThe contractor shall be responsible, as part of his scope of work, to carry out testing and pre-energisation checking of electrical equipment in accordance with methods and procedures laid down hereunder.The Contractor shall appoint a competent person to control all testing and checking activities. This person shall report to and liaise closely with the Engineer in order that testing activities may be conducted and sequenced in a manner best suited to the commissioning programme.Defects revealed during testing and checking which are attributable to the contractor shall be made good by the contractor without delay.Where defects in free-issue supplied equipment are revealed, these should be reported to the Engineer at an early date.

Specific Tests RequiredTesting of electrical equipment shall include, but not be limited, to the following:Testing of MV cables, joints and terminations using the cable manufacturers recommendation, this will vary depending on the type of cable i.e. XLPE or PILC.Insulation testing of up to 1kV power cables using a 2000V hand wound Insulation Tester.Continuity test and phasing out of all cablesPre-energisation testing of transformers.Testing of LV Distribution Switchgear and Motor Control Centres.Testing and measuring of substation earth.Proving correct mechanical operation of moving parts e.g. relays, limit switches, switch or contactor mechanisms, timing devices etc.Spinning of motors to determine correct direction, and recording of no-load and load information.

Pressure Testing of MV CablesEach MV cable shall be tested after installation and before it is energised. Tests shall be carried out after all terminations and joints have been completed. The AC and DC test voltages will be as per the cable manufacturer's recommendations for such tests.

LV Cables (Up to 1kV)All LV cables shall be tested for insulation resistance before installation and after termination (before connecting to apparatus) using a 2 000V DC insulation resistance tester. Insulation resistance values of less than 200megohms before installation shall be suspect and investigated.The end-to-end DC resistance of cores of buried cables shall be measured and recorded in a test certificate.

MV SwitchgearAfter erection, ensure all protection settings have been checked via primary and secondary injection tests. Refer AA Standard STD 543013 Testing and Inspection of Medium Voltage Electrical Equipment.

LV Distribution Switchgear and Motor Control GearAfter erection, all LV distribution switchboards and motor control centres shall be tested for insulation resistance using a 2000V DC insulation resistance tester.Phase to phase and phase to earth insulation resistance values of under 50megohms shall be suspect and investigated.All motor protection devices shall be set at 100% of motor full load current.Check that all isolation and lockout equipment including interlocking tests have been carried out.

TransformersThe MV winding of transformers shall be tested to earth using a suitable insulation resistance tester and the LV winding using a 2000V DC insulation resistance tester. Insulation resistance values of under 500megohms and 200megohms for the HV and LV windings respectively shall be suspect and investigated.Dielectric Loss (Tan Delta / Power Factor) and Swept Frequency Response Analysis tests to be carried out if required by the Engineer. Buchholz relays shall be tested by air or Nitrogen injection. Nitrogen would be preferred.Temperature relays, if fitted, shall be tested by checking the operation of alarm and trip contacts. The contacts are to be set at the alarm and trip values as required by the Engineer.Silica gel breathers shall be oil sealed to the required level and checked for dryness.

Field EquipmentAll field equipment shall be checked in respect of mechanical operation of all moving parts, tightness of connection.Testing shall be repeated each time an installation is disturbed e.g. carrying out of a cable joint.Leakage currents shall be recorded on the test certificate.

The contractor shall ensure safety of personnel during testing operations and this shall include the stationing of a person at the remote end of the cable under test. He shall also ensure that the cable is properly discharged before authorising workmen to proceed with termination work.Testing shall be carried out with the cable in its final position except for the individual cores on each termination, which shall be moved away from their respective connection points.Precautions shall be taken to ensure that the main busbars do not become energised during the testing operations.

Test EquipmentThe contractor shall make available suitable staff, tools and testing equipment, including necessary AC and DC pressure test sets, earth testers, multimetres and clip on type ammeters. Other specialised test equipment that may be required will be provided at an agreed rate in accordance with Special Conditions of Contract at the request of the Engineer.

Tests on Equipment Using Test Voltages Exceeding 1kVThe Engineer will be responsible for authorising the Contractor to carry out these tests. Any safety precautions as laid down or requested by the Engineer must be adhered to.

Test CertificatesAfter completion of the tests detailed above, the contractor shall complete a test certificate showing the results of the test.Appendices to this specification give details of the Project requirements in terms of test certificate format.Completed test certificates shall be handed to the Engineer within seven days of the test. Failure to do so may result in rejection of the test data in which case the contractor would be required to repeat the tests concerned at his expense.

Checking the Completed InstallationAfter each respective installation has been completed, the installation shall be thoroughly checked, by the contractor, against the appropriate test certificate detailed in this specification.Checking shall be carried out before testing commences.Submission of the completed check sheet, to the Engineer, shall indicate that the installation detailed on the respective check sheet/s is complete and ready for inspection and `punch listing' by the Engineer.

Commissioning and Energising of EquipmentPre-commissioning checks, energisation and commissioning of all electrical equipment, other than lighting circuits, shall be the responsibility of the Engineer or his deputy.It is probable that the Engineer will, from time to time, require assistance from the contractor. Upon request therefore, the contractor shall make available, on a day work basis, suitable qualified staff to assist the Engineer with commissioning activities.Motor rotationAfter energising of MCC's, motor will be "bumped" for direction testing. Any motors or other equipment that require direction changes will have two phases swapped at the motor terminal box by the contractor.Defects Found During CommissioningAny defects found by the Engineer during the commissioning shall be rectified by the contractor except where the defect is as a result of faulty manufacture by the supplier of the equipment free-issued to the Contractor and providing that the defect is not as a result of damage occurring during installation by the Contractor.Defects found during commissioning on equipment supplied by the Contractor shall be repaired by the Contractor as quickly as possible.Where it is decided by the Engineer to request the contractor to repair or make good a manufacturing defect the cost of such repairs shall be agreed and written up onto a site instruction before the work is commenced.

Acceptance of WorkThe Contractor is to seek acceptance in reasonably small packages, to avoid duplication of undesirable practices as rectified work is costly in time and money.The Contractor shall utilise the test certificates in preparing work for acceptance and the schedule of rates shall include for any costs involved.Acceptance of work which will eventually be buried or concealed is to be sought at uncovered stages.At the completion of each package, the Contractor shall provide an acceptance certificate for signature by the Engineer.

Appendix A: Referenced documentsAA_REQ_565005, Discipline Requirements Electrical RequirementsThe latest issue of the following documents shall form part of this Requirement:

IEC 62305-3:The protection against lightning

IEC 62305-5-54:Electrical installations of buildings

IEC 62305-1:The protection of Dwelling Houses against Lightning

IEC 60364Low-voltage electrical installations

IEC 60050-851:International Electro-technical Vocabulary Part 851: Electric Welding

IEC 543013:Testing and Inspection of Medium Voltage Electrical Equipment

Appendix B: Record of AmendmentsIssue 0:New Document based on AA STD 565005 (April 2011)

Appendix C: Site Test Certificate Motors

Appendix D: Site Test Certificate Motor Control Centres

Appendix E: Site Test Certificate Transformers

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Sheet1CERTIFICATE NO.

1Manufacturer

2M.C.C. Description

3Current RatingA

4Fault CurrentkA

5Busbar Voltage

6Megger Test on Busbars

Megger Voltage

Red to Yellow

Red to Blue

Blue to Yellow

Red to Earth

Blue to Earth

Yellow to Earth

7Busbar Connections TightYESNO

8Panels Connections TightYESNO

9Buswire Connections TightYESNO

10Earth Connections TightYESNO

11MCC Earth Bar to Main Earth ConnectionYESNO

12Foundations Bolts CompleteYESNO

SIGNED FOR AND ON BEHALF OF THE CONTRACTOR:DATE:

Sheet1CERTIFICATE NO.

1Plant Item NO.

2Transformer duty

3Make

4kVA

5Primary Volts

6Secondary Volts

7Primary Amps

8Secondary Amps

9Vector Group

10Cooling

11Serial No.

12INSULATION TEST

Primary to EarthYESNOm

Test VoltageV

Secondary EarthYESNOm

Test VoltageV

13Temperature AlarmYESNOC

Temperature TripYESNOC

14Buchholz TestedYESNO

15Neutral CT ConnectedYESNO

16Main Earthing CompleteYESNO

17Silica Gel Breather ServicedYESNO

18Conservator Oil Level OKYESNO

19Tap Changer set on TapYESNO

SIGNED FOR AND ON BEHALF OF THE CONTRACTOR:DATE: