part 12 road lighting

7/29/2019 Part 12 Road Lighting

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Section 6 Part 012 General Specification

Rev.0 1/ 33

TABLE OF CONTENTS

12 ROAD LIGHTING ...................................................................................... 2

12.1 GENERAL ................................................................................................ 2

12.1.1 Scope 212.1.2 References 212.1.3 Submittals 312.1.4 Quality Assurance 512.1.5 Delivery, Storage and Handling 5

12.2 SUPPLY OF EQUIPMENT......................................................................... 6

12.2.1 Design Criteria for Columns and Masts 612.2.2 Column and mast fabrication requirements 712.2.3 Specific requirements for columns 812.2.4 Specific requirements for high masts 9

12.2.5 Doors and base compartments for columns & masts 1012.2.6 Luminaires and Lamps 1112.2.7 Cable 1412.2.8 Control Gear 1512.2.9 Distribution Equipment, Cut-outs 1612.2.10 Distribution Equipment Isolators 1712.2.11 Photoelectric Control Units (PECU'S) 1712.2.12 Feeder Pillars 18

12.3 INSTALLATION ....................................................................................... 21

12.3.1 General Requirements 21

12.3.2 Temporary Lighting 2112.3.3 Electricity Supply 2112.3.4 Removal of Existing Installations 2212.3.5 Reuse of Existing Columns 2212.3.6 Wiring in Luminaires and Columns 2312.3.7 Feeder Pillars 2412.3.8 Cable Installation 2512.3.9 Duct Installation 3012.3.10 Performance Testing 31


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12. ROAD LIGHTING

12.1 GENERAL

12.1.1 Scope

1 This Part includes road, street and under bridge lighting and lighting for roadsigns.

2 Related Sections and Parts:

This Section

Part 1, GeneralPart 2, Site ClearancePart 3, EarthworksPart 10 Road signsPart 11, Works in Relation to ServicesPart 13, Traffic Signals

Section 5, Concrete.

3 The National Electricity Cooperation (NEC), Electric Networks Department, NEC(EN) and its Street Lighting Section, may require work to be executed on theirinstallations during the period of the Contract. The Contractor shall afford allfacilities to NEC (EN)s contractors or workmen until their work is complete. TheContractor shall co-ordinate the work of NEC (EN) and his own activities andwhen necessary shall amend his programme of working to suit all requirementsof NEC (EN) and shall keep the Engineer informed in writing of all arrangementsmade.

12.1.2 References

1 The following standards and other documents are referred to in this Part:

BS 65, Vitrified clay pipes, fittings and ducts, alsoflexible mechanical joints for use solely with surfacewater pipes and fittingsBS 88, Supplementary requirements for fuses ofstandardized dimensions and performancefor industrial purposesBS 729, Hot dip galvanized coatings on iron and steel articlesBS 791, Solid-stem calorimeter thermometers

BS 2484, Straight concrete clayware cable coversBS 3871 Miniature and moulded case circuit breakersIEC898 Miniature circuit BreakersIEC 947-2 LV Switchgear and Control GearBS 4343, Plugs, socket-outlets and couplers for industrial purposesBS 4360, Weldable structural steelsBS 4533, LuminairesBS 4848, Hot-finished hollow sectionsBS 5135, Process of arc welding of carbon and carbon manganese steels


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IEC 947-3 Air-break switches, air-break disconnectors, air-break switchdisconnectors and fuse combination units for voltages up to and including 1000V a.c. and 1200 V d.c. BS 5467, Cables with thermosetting insulation forelectricity supply for rated voltages of up to and including 600/1000 V and up toand including 1900/3300 VBS 5486, Requirements for type-tested and partially type-tested assemblies

BS 5489, Road lightingBS 5649, Lighting columnsBS 5972, Photoelectric Control Units for Road Lighting. BS 6121, MechanicalCable Glands for Elastomer and Plastic Insulated CablesBS 6141 PVC insulated pvc sheathed circular flexible cablesBS 6346, PVC-insulated Cables for electricity SupplyBS 6360 High conductivity stranded copper shaped conductor with XLPEinsulationBS 6622, Cables with extruded cross-linked polyethylene or ethylene propylenerubberinsulation for rated voltages from 3800 6600 V up to 19 000/33 000 VBS 6746 Extruded black pvc over sheath

BS 7671 Requirements for electrical installationsBS 7430, Code of practice for earthingBS EN 60529, Degrees of protection provided by enclosuresBS EN 60598, Luminaries for roadway lighting

Institution of Lighting Engineers (ILE), Code of Practice for Electrical Safety

ISO 9002, Quality assurance in production andinstallation

Institution of Electrical Engineers (IEE), WiringRegulations

Ingress Protection IP22, Electrical cut-out protectionIngress Protection lP54, Electrical enclosure dust and water proof ratingsIngress Protection lP66, Classification of compression glands

12.1.3 Submittals

1 Before beginning the installation, the Contractor shall confirm in writing to theEngineer that he has obtained approval from concerned authorities of theclearances provided to overhead and underground lines.

2 The Contractor shall not order any equipment before approval has been givenin writing by the Engineer. The approval procedure shall be as follows:

(a) contractor submits his proposal to the Engineer (4 copies). Allsubmissions shall give clear, detailed characteristics of the equipmentproposed, together with calculations, where necessary, includingcatalogue identification references. Documents shall be in the English andArabic languages

(b) the submission shall be comprehensive and clearly state anymanufacturer's deviations from the specification


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(c) manufacturer's literature with the submission shall be originals and notphotocopies.

(d) the submission will be reviewed by the Engineer(e) the submission will be submitted to concerned authorities Street Lighting

Section with the Engineers comments to obtain their approval(f) approval will be transmitted to Contractor in writing after receipt of NEC

Street Lighting Section approval.

concerned authorities reserves the right to direct the Contractor to provideequipment of a make and type which is essential to achieve the design criteria.

3 The Contractor shall at his own expense, present samples to the concernedauthorities Street Lighting Section of each type of equipment to be used whichshall exactly conform to the designated requirements. The samples shall onlybe submitted after approval of their technical characteristics.

4 Approval of samples by concerned authorities Street Lighting Section shall notin any way relieve the Contractor of his contractual obligations in respect of thesuitability of the equipment or its final performance once installed and for the co-ordination of the elements into a fully operational installation.

5 The design and manufacture of columns shall comply with BS 5649 and all testcertificates for the columns shall be provided to the Engineer at least five daysbefore the columns are delivered to site.

6 The Contractor shall provide the required shop drawings and calculations aswell as the provision of all literature and samples in connection with theapproval of proposed equipment.

7 The Contractor shall submit calculations on each cable to confirm that theinstallation meets the requirements of the current IEE Wiring Regulations asfollows:

(a) maximum volt drop is not exceeded(b) equipment to be installed is of sufficient rating for the prospective fault

current(c) disconnection time is satisfactory(d) cable is of sufficient current carrying capacity for the load under running

and starting conditions(e) protective devices shall discriminate fully as intended.

8 The Contractor shall keep duplicate daily records on drawings of all workcarried out as work proceeds, one copy of which shall be kept available for theuse of the Engineer. On completion of the work, one copy of the daily records

shall be handed to the Engineer.

9 Electrical schematics shall show the method of cabling to all items of electricalequipment as installed. The Contractor shall provide full manufacturers datasheets for all equipment installed.

10 The Contractor shall prepare and hand to the Engineer within thirty days of thedate of the completion of the Works the designated number of sets of recorddrawings which shall be prepared on copies of the contract drawings or


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transparencies. The record drawings shall include the following:

(a) technical details of every type of equipment installed, including operatingand maintenance instructions

(b) the drum number for underground cables(c) lighting circuit arrangement and schedules. The drawing shall fully

indicate (with accurate dimension) the size, type and position ofequipment cables, ducts, joints and feeder pillars with particular regard forthe need to accurately locate buried cables after completion

(d) spares list(e) test certificates, including lantern carriage winch test certificates(f) test result.

11 Within the time stated above, the Contractor shall submit two copies of therecord drawings for the approval of the Engineer. After receipt of such approvalthe Contractor shall provide one set of reproducible transparent negativedrawings and two sets of prints on paper to the Engineer for his retention.

12 In addition to the foregoing, the Contractor shall provide in each distribution unita good quality print on paper showing the street lighting distribution line diagramof that particular section. These prints shall be mounted on the inside of thedoor of each distribution unit, be of an adequate size to be legible and shall becovered in clear plastic to prevent undue deterioration.

13 In order to achieve accurate record drawings, all relevant information relating tothe Works shall be entered on to drawings kept for the purpose immediately theWork has been carried out. The marked prints shall be available for inspectionat the Contractors site office at any reasonable time during the progress ofwork.

14 The Contractor shall prepare and hand to the Engineer within thirty days of the

date of Completion of the Works the designated number of sets of operationand maintenance manuals. The Engineer will decide on the scope and detailrequired for the operation and maintenance manuals.

15 Operating instructions for the lantern carriage winches shall be placed in aprominent position on the high mast. Operating instructions shall be provided ona durable media and not vulnerable to vandalism.

12.1.4 Quality Assurance

1 Road lighting works shall be carried out by specialist contractors or

subcontractors having experience in the provision and installation of lightingcolumns, provision and laying of cables and ducts, and provision andinstallation of supply connections to all electrical equipment. Specialistcontractors or subcontractors shall be prequalified by concerned authoritiesStreet Lighting Section for new street lighting installation.

2 All cables shall be certified by the manufacturer as suitable for installation inUAE


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3 All materials shall be approved by concerned authorities before ordering. Onlyproducts with a proven record of performance, efficiency and long life will beconsidered for approval by concerned authorities.

4 All works, equipment and materials shall comply with statutory and otherregulations, Codes of Practice and Standards current at the date of Tender

including the UAE Wiring Regulations

5 All columns and brackets shall be produced by lighting column manufacturersregistered and certified for the manufacture, supply and certification of lightingcolumns under their quality assessment schedule to ISO 9002.

6 Column manufacturers not registered and certified accordingly will only bepermitted if a satisfactory submission is made for quality assurance.

7 Facilities shall be provided for the Engineer to inspect the lighting columnsduring the course of manufacture and application of protective treatment.

8 Any equipment or items damaged in transit will not be acceptable forincorporation in the works and the Engineer shall have the right to reject suchitems. In the case of minor damage to galvanising or painting the Engineer maypermit repairs to be carried out. Any such repairs shall be carried out inaccordance with the recommendations of the supplier.

12.1.5 Delivery, Storage and Handling

1 Each drum of cable shall be accompanied by duplicate copies of testcertificates, bearing the cable description and name of manufacturer. Suchcertificates shall be handed to the Engineer.

2 Cable drums must have an indication of the length, size of cable and thenumber of cores it contains.

3 Cables stored in the open in unshaded locations which are liable to strongdirect sunlight must be protected unless the cable supplier confirms that thecable is capable of withstanding the conditions without deterioration orreduction in the predicted life.

4 All cables shall be delivered to site with the manufacturers' seals, labels, orother proof of origin intact such labels and seals shall not be removed until thecable is required for use, and shall be retained for inspection.

5 All column delivered to the site shall be stored clear of the ground by placing on

blocks. Care shall be taken to avoid damaging column and mast sections byplacing them on top on one another.

6 The Contractor shall submit a detailed method statement giving details of theproposed method of lifting the columns into position. Lifting methods shalladequately address safety and avoid damage to columns and masts.

12.2 SUPPLY OF EQUIPMENT


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12.2.1 Design Criteria for Columns

1 For all columns the stress and deflection calculations shall be based on themaximum bracket and luminaire projection, on the bracket arm, with projectedarea, length and weight as designated.

2 In still air conditions, loaded with the designated luminaires, positioned in any ofthe variable locations, there shall be no appreciable deflection of the column ormast.

3 The maximum permissible deflection in the column or shall be 1 deg. in any 1 mlength with a maximum total of 7.5 degs. over the whole shaft under themaximum design wind loading.

4 Columns shall be steel & designed in accordance with BS 5649.

6 Columns must be designed to withstand a wind force gusting up to 120 km/h.

7 The "K" factor for columns over 8 m in height shall be 2.2.

8 Columns shall be designed to support lanterns with the data given by theEngineer.

9 All columns of the same mounting height and with the same arrangement shallbe identical in construction.

10 Column bracket arms and spigots shall be so designed that when assembledwith the column shaft the design attitude of the arm and projection shall be asdesignated.

11 The luminaire fitting spigot shall be 42 mm diameter by 125 mm length unless

otherwise designated, or of a length and diameter to suit the luminaire.

12 The securing arrangement of the bracket arm to the column shall be positive toensure that the arm does not rotate and shall be such that the bracket can be

fixed in any one of four 90 positions in relation to the column door opening.Bracket fixing screws shall be of stainless steel.

13 Bracket arms shall be so designed that when assembled with the column shaft

the design attitude of the arm and spigot shall be 5 above the horizontal.

14 The mounting height and bracket projection of each column shall be asdesignated. Mounting height shall be measured from the surface of the

carriageway to the photometry centre of the luminaire and the bracket projectionshall be measured from the centreline of the column shaft to the centre of theluminaire.

15 Each column shaft shall be suitable for use with any bracket outreach specifiedfor a given mounting height.

16 Each type of high mast column shall be supplied with foundation drawings,foundation bolts and four nuts. Bolts and templates and two spanners for each


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type of nuts must be supplied.

17 For columns, four slots as designated are to be provided on a flange plate ofsuitable size for foundation bolts to fix the column on the foundation.

18 The manufacturer of the street lighting column shall prepare and supply the

detailed specification, dimensions and design for reinforced concrete columnfoundations.

12.2.2 Column fabrication requirements

1 All columns shall be hot dipped galvanised to BS 729 Part I or BS 791/71.

2 Street lighting columns shall be steel, tubular stepped in shape with a baseflange with foundation bolts, nuts, washers, wooden base board and earthingterminals.

3 Strengthening shall be provided at door and compartment openings. Care shallbe taken to ensure that rounded edges are provided at the corners of door andcompartment openings to avoid any stress concentrations.

4 The column shall be made from hollow section to BS 4848 Part 2 in steel to BS4360 grade 43C or any other approved equivalent norms. The hollow sectionshall have minimum tensile strength of 430 MPa and minimum field stress of at255 MPa.

5 Columns shall be in one piece tubular (round) stepped shape and flanged(bolted) type.

8 Welding shall comply with the requirements of BS 5135 as appropriate. Detailedwelding procedures and procedure trials, if required, shall be in accordance withBS 5135.

9 Columns with a joint above the base section are not acceptable.

10 Columns manufactured from tubular steel of circular cross-section shall have asingle swaged or sleeved joint only at the point where the base section meetsthe reduced shaft diameter.

11 The completed column shall be truly vertical and the angle of the luminaire shallbe checked so that it is square to the column, horizontal in end elevation andsimilar to all other luminaires in the installation.

12 The base flange plate is to be manufactured from steel plate which is free fromlamination.

13 The main shaft of the pole penetrates the full depth of base plate and is to bewelded above and below using a semi-automatic MIG shielded arc process.Any additional strength is to be provided by gussets located between holepositions.


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12.2.3 Specific requirements for columns

1 The top of the column shall be designed and provided as suitable to fix thebracket arm collar with the top of the column.

2 Threaded holes for Allen socket screws on top of the column on the required

sides are to be provided.

3 All dimensions for tubular round columns shall be according to Table 12.1 orTable 12.2. All dimensions are in mm.

Table 12.1Schedule of Dimensions for Tubular (Round) Columns

Dimension/ Detail Height

6m 8m 10m 12m

Length of column (without bracketarm)

4250 6020 8000 9500

(between flange plate and columnonly)Thickness of the column 4 4 4 4Bottom of the column - insidediameter

192 192 192 192

Bottom of the column - outside 200 200 200 200diameterDistance between columns baseflange

400 500 500 500

plane to door openingSize of door opening 600x140 600x140 600x140 600x140

Distance between door openings NA NA NA 100Length of base compartment 1170 1270 1270 2000Door opening top to top of thecolumn

3080 4750 6730 7500

Outside diameter of the top of the 70 70 102 102columnInside diameter of the top of the 62 62 94 94columnDetails and size of base flangeplate

450 x 450 450 x 450 size varies size varies

x 10 thick. x 20 thick. 20 thick. 30 thick.Four foundation bolts with two nuts

and 800 x 25 800 x 25 800 x 25 900 x 33washers per bolt


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Table 12.2Schedule of Dimensions for Octagonal Columns

Dimension/Detail Height

6m 8m 10m 12m

Length of column (withoutbracket

4800 6500 8000 9985

arm) (between flange plate andcolumn only)Thickness of the column 4 4 4 4Bottom of the column - inside 148 183 242 242diameter (across flat)Bottom of the column - outside 156 191 250 250diameter (across flat)Distance between columnsbase

400 500 500 500

flange plane to door openingSize of door opening 600x100 600x130 600x135 600x135Door opening top to top of the 3800 5400 6900 8885columnOutside diameter of the top ofthe

60 60 78 78

columnInside diameter of the top ofthe

52 52 70 70

column

Details and size of base flange450 x 450 x10

450 x 450 x10

sizevaries

size varies

plate thick. thick. 20 thick. 30 thick.four foundation bolts with twonuts

800 x 25 800 x 25 800 x 25 900 x 33

and washers per bolt

12.2.5 Doors and base compartments for columns

1 Each column shaft shall have a base compartment large enough to offer easyaccess to the equipment therein.

2 A weatherproof door shall be provided for each opening which shall beinterchangeable between columns of the same mounting height. To avoid

accidental spillage of water from irrigation of flooding the bottom of the doorshall be at least 0.5m above the top of the foundation.

3 A stainless steel durable non-corroding tamper-proof lock device shall beprovided of the triangular headed screw type, unless designated otherwise.Where applicable, door lock recess shall incorporate adequate drainage suchthat they are unlikely to become blocked and so form a water trap.


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4 Door openings are to be kept to the minimum size consistent with the cabletermination units and any control gear.

5 Doors shall be located at 180 to the kerb line so that they doors can beopened at all times without encroaching onto the highway. The door openingsand cable slots shall be free from any irregularities and burrs.

6 Keys are to be provided with the first consignment of columns at the rate of 10% of the total number of columns.

7 Cable entry slots shall be 50 mm wide x 150 mm long, and shall be positioneddirectly below the door opening. The lower edge of the slot shall be 500 mmbelow ground level.

8 A baseboard of non-hygroscopic hardwood, minimum thickness 15 mm, shallbe securely fixed in each compartment and shall be of sufficient size toaccommodate the cable termination unit.

9 Single purpose earth terminals shall be provided in a readily accessibleposition, preferably on the left hand side of the opening and on the columndoor.

10 A brass or stainless steel nut and bolt arrangement shall be used as the methodof fixing. A spring clip device is not acceptable as a fixing method.

11 All door lock hinges and catches shall be regreased before handover.

12 Columns shall be numbered in accordance with NEC Street LightingRegulations.

12.2.6 Luminaires and Lamps

1 The luminaires for roadway lighting shall be to BS EN 60598 Luminaires forroadway lighting or equivalent at designated mounting heights.

2 The luminaires shall be capable of achieving the performance specificationrequirements set out in the contract according to BS 5489.

3 The number, type and power rating of the luminaires shall be as shown in theschedule of luminaires.

4 Luminaires shall be complete with integral control gear for use withelliptical/tubular lamps.

5 The sections of the luminaires shall fit together tightly to prevent the entry ofdust and water to protect the control gear and shall comply with IP 66. Asbestosgaskets shall not be used.

6 The control gear shall be in a compartment with an IP 43 rating and shall beprewired and mounted on a gear tray which is firmly secured. Electricalcomponents shall be protected from the direct heat from the lamp.


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7 Provisions shall be made to allow easy access to the lamp and control gear formaintenance or replacement.

8 The optical system shall comprise of a reflector made from pressed high purityaluminium that is anodised and polished.

9 The incoming cable terminal block and earth fixing screw shall be securely fixedto the gear tray or the Metallic body of the luminaire and a cable restrainingdevice shall be mounted close to the terminal block.

10 The spigot entry of the luminaire shall be compatible with the brackets to besupplied.

11 The colour of the luminaire body shall be grey unless specified elsewhere in thecontract.

12 The technical data for the luminaire shall clearly state the wind area to be usedfor structural calculations for the columns or masts.

13 A cable holder shall be mounted near the terminals in a metallic compartment.The side entry mounting socket accepts a 125 mm long spigot and 50 mmdiameter or adjustable from 45 mm to 60 mm. The exterior side of bothcompartment shall be with grey colour finishing.

14 All luminaires shall be supplied complete, tested and ready for working andshall be fitted with all necessary starters, igniters, ballasts, and power factorcorrection capacitors to give a minimum power factor of 0.85 lagging.

15 Luminaires shall be designed so that any moisture collecting in the bracketcannot enter the luminaire. Drain holes in the luminaire protector are notacceptable.

16 All electrical equipment shall be mounted on a detachable gear tray which mustbe securely fixed to the main body in such a way as to ensure good earthingcontinuity. Where the optical system includes metal reflectors, they shall befaceted, one-piece reflectors of high purity on oxidised aluminium. On removalfrom the fitting, the reflectors shall be capable of being refixed in the correctoptical relationship to the light source, without adjustment.

17 Lamp supports shall be arranged to ensure constant register of the lamp inrelation to the optical control system in all conditions.

18 Reflectors and other components which require cleaning shall be free from

sharp edges and projections which might cause injury.

19 The luminaire protector shall be made of glass or acrylic which has a smoothexterior. The protector or one piece sealed optic shall be securely attached tothe luminaire, but capable of easy removal and replacement.

20 Luminaires shall be supplied with earth terminal and with lamp holders wired to

a terminal block in heat resisting non-hygroscopic insulated 0.75 mm2

stranded


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copper conductors, cleated to prevent movement and to ensure that no cableshang below the luminaire canopy.

21 An earth connection is to be provided in the control gear compartment. Whenaccess to this compartment has been attained, the earth connection shall bevisible and readily accessible without removing any components, and all

Metallic components shall be earthed to this point.

22 If the control gear compartment is provided with its own cover, the latter shall beadequately hinged with the cover in the open position. The terminal block shallbe shielded with suitable insulating material to prevent contact during lampreplacement and routine maintenance. The shield is to be captive in that it shallnot be necessary to completely detach it from the luminaire to inspect theconnection at the terminal block.

23 Luminaires are to be designed for easy wiring and repair. The lamp supportdevices or optical reflector mirror shall be such that all optional choice positionsare clearly and permanently marked.

24 Luminaires shall be fitted with a standard plug and socket arrangementmounted on the body and suitable for use with a three lugged bayonet fittingphotoelectric control unit. The socket shall be permanently wired to theluminaire terminal block. A weatherproof gasket shall be provided between thesocket and canopy and the socket shall be securely fixed by not less than threescrews. The socket mounting shall be such that the canopy can be removed togive access for maintenance to the luminaire without removal or disconnectionof the socket. The socket shall be constructed of glass filled nylon to BS 5972and offering Class II protection from electric shock as defined in BS EN60598.

25 Lighting units for all types of high mast columns shall be cut-off flood lights each

with tropicalised control gear of 240 V, up to 1000 W SON-T high pressuresodium lamps. The lighting distribution shall be adjustable with bothsymmetrical and directional distribution capability.

26 High pressure sodium vapour gas discharge elliptical lamps of 400 W, 220/240V and 50 Hz will be SON-T type with an elliptical bulb with a diffusing coatingwith E-40 base. Lamps shall be suitable for use on 220-240 V 50 Hz a.c. powersupply. Lamps shall have a built-in igniter with self-igniter. Initial luminous fluxoutput shall be 47 000 lm.

27 High pressure mercury vapour fluorescent elliptical lamps of 125 W, 220/240 Vand 50 Hz and E-27 base will be MBF/U type with an elliptical outer envelopewith inner surface coated with a fluorescent power which convert ultravioletradiation into visible radiation, or light. These will be suitable for use in universaloperating position. Initial luminous flux output shall be 6200 lm.

28 Low pressure sodium tubular (SOX) lamps of 180 W, 220/240 V 50 Hz shall beSOX type with a discharge tube enclosed in a clear tubular outer envelope andBY 22 base. Lamps shall have a built-in, igniter with self-igniter. Initial luminousflux output shall be 33 000 lm.


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29 High pressure sodium vapour gas discharge tubular lamps of 1000 W, 380/440V and 50 Hz shall be SON-T type with clear tubular hard glass envelope with E-40 base. Lamps shall be suitable for 380/440 V, 50 Hz a.c. power supply.Lamps shall have a external igniter, without self-igniter. Initial luminous fluxoutput shall be 135 000 lm.

30 High pressure sodium vapour gas discharge tubular lamps of 400W to 50W,220/240 V and 50 Hz shall be SON-T type with clear tubular hard glassenvelope with E4-40 base. Lamps shall be suitable for 220-240 V, 50 Hz a.c.power supply. Lamps shall have either a built-in or external igniter. Initialluminous flux output shall be:

Table 12.3Initial Luminous Flux Output of Lamps

Wattage Luminous Output

400 55000

250 32000150 16500100 1050070 660050 4400

12.2.7 Cable

1 All cable shall be in accordance with part 6 of section 21 of the GeneralSpecification and the following requirements

2 All cabling to and between columns shall be multicore XLPE insulated steel wire

armoured and PVC sheathed to BS 5467 rated 600/1000 volt. Damaged cablesshall be replaced. Cables shall not be pulled out to straighten them after layingand cable stockings shall be used for all cable hauling.

3 Underground through joints and tee joints are not allowed.

5 Unless otherwise designated, all cable oversheaths shall be black for LVcables.

6 All cable lengths shall be measured checked and confirmed before ordering orinstalling cables.

7 Cable drums shall be supported by suitable purpose made jack stands andaxles while the cables are being drawn off. In no circumstances shall drums berolled in a direction other than indicated on the side of the drum.

8 Where cables are pulled into ducts, sufficient rollers shall be used to guide thecables so as to prevent contact with the duct ends.

9 All designated cable lengths are net lengths and approximate only.


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10 All cables shall run directly from point to point without joints unless the lengthrequired is in excess of the length obtainable in one piece from the cablemanufacturer.

11 Three - phase groups of single-core cables shall be laid, wherever possible, intrefoil formation and touching each other.

12 Multi-core SWA cables in trenches or ducts shall be single wire armoured. Steeltape armouring will not be permitted.

13 The maximum permitted voltage drop at the furthermost column cut-out, undernormal conditions, shall be 8 V below feeder pillar incoming voltage.

14 The means of identification of the cable shall be one or other of the following:

(a) an engraved plastic or brass label securely fixed to the cable sealing box(b) a stamped brass or aluminium label securely tied to the cable close to the

sealing box with galvanised iron or tinned copper binding wire.

15 Self-adhesive embossed plastic labels will not be accepted as permanentmeans of identification.

16 The means of identification shall give the cable size, number of cores, andfunction together with the cable reference number if one has been allocated.

17 All cables above ground in feeder pillars or sub-stations shall be identified bymeans of engraved or stamped plastic or brass labels. The labels shall beardetails of the code size, number of cores, function, and reference number (ifany) and shall be securely attached to the cables with galvanised iron or tinnedcopper binding wires.

18 All cables running underground shall be identified at joint positions, in draw pits,and elsewhere at intervals not exceeding 30 m, by means of heavy gaugestamped brass labels securely fixed with at least two ties of heavy gaugegalvanised iron binding wire.

19 The cores of all control cables shall be individually identified, at terminations, bymeans of approved plastic ferrules bearing indelible characters, in accordancewith the numbering on the relevant wiring diagram.

12.2.8 Control Gear

1 All items of control gear shall be fitted with shrouds over all terminals to prevent

accidental contact by persons.

2 The control gear shall have a clearly marked circuit diagram or other marking toshow the terminal connections in relation to all other components. A separateearth terminal shall be provided on all components.

3 The capacitor shall have an aluminium body. Control gear (choke, capacitor,igniter and related items) shall be suitable to withstand temperatures up to 86

C. Internal connections shall be with heat resistant wire and with porcelain or


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nylon connectors.

4 Ballasts shall also be suitable for use at single phase voltage designated by theEngineer and shall be reasonably silent in operation.

5 All tappings shall be brought to suitably marked standard terminals to which

lamp and supply connections shall be made. Ballasts shall be mounted withinthe body of the luminaire.

6 Igniters shall be mounted within the body of the luminaire. Each igniter shall befitted with a device which will detect the presence of a faulty lamp andautomatically limit the generation of HV pulses. Igniters shall be suitable for usewith lamp, ballast and PFC capacitor included in the control gear set.

7 Non-metallic capacitors shall be supplied with a fixing band which shall notdamage the capacitor when fitted and, if metallic shall be provided with aseparate earth terminal.

8 Capacitors shall have a tolerance of 10 % of marked value.

9 All electrical sockets shall be BS 4343 type, IP54 minimum, or manufacturersstandard.

10 All electrical sockets shall be BS 4343 type, IP54 minimum, or manufacturersstandard.

12.2.9 Street Lighting Cut-outs

1 Cut-outs in columns shall be phenolic moulded, three phase, and suitable for

looping two 25 mm2

cables.

2 Cut-outs shall:

(a) be to BS 88 Part 2(b) be of the combined single phase and neutral type(c) incorporate an earth terminal

(d) be suitable for concentric or PVC armoured cables of up to 25 mm2

cross-sectional area with capacity for looping in and out

(e) have all metal parts tinned(f) be provided with a minimum of 2 fixing screws(g) be manufactured from material which is non-hygroscopic and non-

tracking.

3 Terminals and contacts shall have a rating of not less than 40 Amp and besuitable for BS 88 fuses of 6 A, 12 A, 16 A or 20 A ratings, selected from thetable below:

Wattage 50W 70 W 100 W 150 W 250 W 400 WFor 1Lamp 6 6 6 6 10 10For 2 Lamps 6 6 6 6 16 10For 3 Lamps 6 6 10 10 16 20


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4 The cut-outs shall comply with the 16th Edition of the IEE Wiring Regulations.

5 A cut-out used as a means of isolation shall have the facility for padlocking.

6 The service cut-out shall have a moulded enclosure, offering a minimum

protection of IP22, capable of withstanding severe impact.

7 Separate terminals shall be provided for live, neutral and earth conductorscomplete with terminal shields to prevent accidental contact with all liveconductors.

8 Cut-outs shall be sized to accommodate the designated cables, but with a

minimum of 25 mm2

cables.

9 Cable armouring shall be bonded as an integral part of the cut-out, andcomplete with cable armour clamp shrouds.

10 The cut-out shall be suitable for mounting on a wooden back board or DIN rails.

12.2.10 Distribution Equipment - Isolators

1 The isolators shall be switch disconnectors, with fuses where appropriate,complying with IEC 947-3 (previously BS 5419), AC22 class of duty, with anominal rating of 32 A and be 2-pole or 4-pole as appropriate.

2 Isolators shall be capable of clearing the designated short-circuit fault currentfor 3s duration.

3 Where switches operate by manual operation, the speed of operation shall beindependent of the effort of the operator.

4 The isolator shall be DIN-rail mounted in a non-metallic, weatherproof, impactresistant moulded enclosure with a lockable hinged cover.

5 The unit shall be suitable for mounting in the base compartment of a lightingcolumn.

6 Isolators shall provide in-built switch fuse loop terminals for downward loopfeeds to traffic signs, bollards and related equipment.

7 Isolators shall incorporate a locking facility to the off' switch position only.

8 All isolating devices shall be 2-pole for single phase systems or 4-pole for threephase systems.

9 The isolators shall be rated to suit the local environmental conditions of UAE.


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12.2.11 Photoelectric Control Units (PECU'S)

1 All PECU'S shall be guaranteed for a period of six years. Any unit failing withinsix years shall be replaced with a new unit.

2 The PECU'S shall be installed on a luminaire mounting at the nearest lighting

column from the feeder pillar. Three core, 6 mm2

cu PVC SWA PVC cable shallbe provided to connect the PECU'S to the feeder pillar.

3 The photoelectric cell shall be controlled by a 4 A HBC control fuse within thefeeder pillar and shall be completely weatherproof and not affected by moisture,vibration or changes in temperature and capable of continuous satisfactoryoperation over extended periods in an ambient temperature of up to 60 C.

4 A suitable manual override switch shall be installed to permit usage at timesoutside the periods during which the lights normally operate.

5 The cell shall operate at an illuminance pre-set to ON 80/100 lx and the ratio of

ON to OFF shall be approximately 1 to 2.

6 A minimum 15 s delay shall be provided to ensure that transient switching doesnot occur.

7 The control system in the feeder pillar shall be such that a time switch shall actas an override in the event of a failure of the photocell control unit

8 The time switch shall be a weatherproof, 24-hour dial time switch motor drivenwith a clock accuracy of 5 min/year and shall have a 48-hour synchronousspring release (manually rewindable) to maintain clock operation and outputswitching during power supply failure.

9 Power supply shall be 240 V, 50 Hz and output contact rating shall be 30 A at240 V (resistive).

10 PECU'S and their associated relays (or other switching devices) shall haveprematched responses and shall be housed in the same envelope.

11 Where the load to be switched is greater than the PECU can switch directly, acontactor shall be used.

12 The cell shall be hermetically sealed against the ingress of moisture and shallbe contained in a strong impact resistant low profile translucent housing, thesurface of which shall be non-oxidising and impervious to discoloration.

13 No provisions shall be made for adjustment to the calibration. There must be noneed to orientate the switch to give a specified operation.

14 Provided that the month and year marks on the units are current when supplied,this date will constitute the start of the guarantee period for the PECU.

15 In all cases, the switching level of 70 lux shall not vary more than plus or minus10 % during the guaranteed life of the unit.


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Rev.0 19/ 33

12.2.12 Feeder Pillars

1 All parts of equal size and rating shall be interchangeable. The number of jointsshall be kept to a minimum. Bolted electrical joints shall be secured by corrosionproof bolts with locking washers.

2 Where designated or directed by the Engineer, the enclosure shall haveprovision for expansion by the addition of extra outgoing ways.

3 Shells shall be constructed of galvanised sheet steel, cast-iron or glassreinforced plastic as directed by the Engineer.

4 Roofs shall be constructed of galvanised steel, cast iron or concrete asdesignated or directed by the Engineer. Where concrete bases are designated,suitable bolting flanges for mounting onto concrete plinths shall be provided.Removable aprons shall be provided to permit installation of cables from below.

5 Outdoor weatherproof free-standing feeder pillars shall be provided as

designated or as directed by the Engineer.

6 The cabinets shall be reinforced fibreglass polyester enclosures constructed tominimum IP54 mounted on a suitable concrete foundation. The cabinets shallbe lockable and shall be provided with a means of ventilation by a free passageof air through the unit, but this shall not reduce its overall degree of weatherprotection. All equipment contained within shall be suitable for the climaticconditions of UAE

7 Feeder pillars shall comply with the relevant parts of BS 5486 except asotherwise designated in this Part.

8 Enclosures shall be lockable and fully weatherproof to the designated IP rating.IP ratings shall be in accordance with BS EN 60529. Materials, construction andfinishes shall be suitable for the conditions of temperature and humiditydesignated by the Engineer, taking into account any temperature rise due todirect sunlight. All metal parts shall be plated, galvanised or painted withcorrosion resistant finishes. The finish shall provide protection against corrosioncaused by tannic and other acids in falling leaves.

9 The fault rating of feeder pillars shall be such that they are able to carry the fullprospective short-circuit current designated by the Engineer for a minimumduration of 1 s without damage. All conductors shall be copper.

10 Where designated or directed by the Engineer, a means of isolation shall be

provided on the incoming supply. Provision shall be made for padlocking in theopen position.

11 Busbars of full rating, making allowance for holes, shall be constructed of hard-drawn, high conductivity copper and mounted on insulators at the rear of thedistribution pillar. Busbars shall be insulated with non-hygroscopic, non-trackinginsulation and all live parts shall be insulated, screened or shielded.

12 Neutral conductors shall be insulated from earth to allow use on TN-S systems.


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Rev.0 20/ 33

Neutral connectors shall have separate connections for each outgoing cable.

13 Where feeder pillars have out paths of greater than 100 A capacity, busbarsshall be provided for neutral and earth connections.

14 The neutral busbar shall be mounted in parallel with the phase busbars and

arranged so that each neutral connection is physically identified with theappropriate circuit. A separate earth bar shall be provided at the bottom of thefeeder pillar and shall be of sufficient length to accommodate a discreteconnection for each circuit including 25 % spare capacity. The minimum cross-sectional area after drilling of holes shall be as specified in BS 7430.

15 Neutral busbars and connections shall have the same rating as the associatedphase conductors. Neutral connections shall be clearly labelled with the circuitreference of the associated fuse or circuit-breaker.

16 The neutral bar shall be colour marked black and the earth bar green andyellow. The colouring of bars shall not be continuous unless it is also the

insulating medium otherwise the colour marking shall be such that it cannot bemistaken for an insulating covering.

17 Insulated dividing barriers shall be provided between phase contact assembliesand between phase and neutral. The barriers shall be constructed so that it willnot be possible to insert a fuse link or circuit-breaker between phases orbetween phase and neutral.

18 Where link disconnectors are designated, they shall incorporate contacttightening devices on both fixed and hinged contacts. Suitably insulatedoperating tools for tightening the contacts shall be provided in each feederpillar. Feeder pillars shall contain a 3-pole moulded case circuit breaker of a

suitable size (minimum 100 A), a 4-pole contactor suitably rated (contacts shallbe fitted with a snap action to prevent chatter) with 240 V a.c. coil within IP54enclosure and a 3-phase MCB distribution board complete with single pole M9Type 3 miniature circuit breaker (minimum 20 A rated).

19 Where distribution boards are required, they shall be totally enclosed ingalvanised steel or plastics cases. Distribution boards shall be MCB type, withmain RCD device protecting all outgoing from the board.

20 Supply to feeder pillars will be at 415 V, 50 Hz, 3-phase, 4-wire plus protective

conductor and will generally be provided by up to two 75 mm2

4-core PVCcables. Two suitable type CW cable glands with shrouds shall be provided for

termination of these cables.

21 An appropriate number of single phase and neutral MCBS for each circuit with

cable glands to take up to 25 mm2

cable shall be provided in each cabinet.

22 All MCBS and protective device shall be rated to withstand a short-circuitcurrent of 9 kA or the scheduled value if higher.

23 The pillars shall be generally wired as designated. Each column along a circuit


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Rev.0 21/ 33

route shall be connected to a different phase within each line of three (Red,Yellow, Blue) to give a balanced overall circuit load. Each feeder pillar may onlysupply right, 3-phase circuits, and the circuit cable runs shall have a length notexceeding 1000 m.

24 Twenty five percent spare capacity shall be allowed within all distribution

boards.

25 Fuse protection shall be in the form of BS 88 fuses in shrouded fuse carriers. Allfixing and connection access shall be from the front.

26 Outgoing circuits shall be labelled with the circuit reference and the fuse orcircuit-breaker rating.

27 Where designated, a metal clad anti-condensation heater shall be provided atthe bottom of each feeder pillar in such a position that it is accessible but doesnot impede cable access. It shall be shielded to prevent contact The rating ofthe heater and the means of control shall be as directed by the Engineer.

28 All internal wiring shall be enclosed in trunking or conduit. Access to cableterminations shall be by means of a removable cover plate.

29 All cable access shall be from the front with entry from below.30 Cable entry and termination provisions shall be suitable for the designated size

and type of cable or as directed by the Engineer

31 Cable terminators arrangements shall be suitable for compression lugs orbolted clamps. Cable support cleats shall be adequate to support the cables innormal service and to restrain them under fault conditions. The arrangementshall be such that all cable terminations can be readily made from the front.

32 An earth electrode shall be installed at each feeder pillar and shall have aresistance to true earth of not more than 10 ohms. The size of the electrode

shall be 16mm2

by 2.5m length and shall be driven to a depth that penetratesthe summer water table by at least 2m. The earth bar shall be connected to theearth electrode by means of a stranded copper conductor of minimum cross-

sectional area of 70 mm2

.

12.3 INSTALLATION

12.3.1 General Requirements

1 The Contractor is responsible for all liaisons with concerned authorities StreetLighting Section in respect of programming the installation and commissioningof the complete street lighting system. He shall ensure that concernedauthorities Street Lighting Section are at all times kept informed of the currentprogress of the work and that his approved subcontractor programmes the workin the designated sequence in accordance with the approved programme.


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Rev.0 22/ 33

2 The Contractor shall excavate and backfill all trenches required for theinstallation of cables and ducts in accordance with part 3 of this specification.

3 The Contractor shall reinstate surfaces disturbed by his operations and providetemporary reinstatement as directed by the Engineer.

4 The execution of all electrical work shall be supervised by a qualified personwith a thorough experience in road lighting and associated equipment.

5 Only workmen who have had experience in the erection of road lighting shall beemployed on the work of erection.

6 Before carrying out any electrical works to existing services, authorisation mustbe obtained in writing from all relevant authorities.

7 The Contractor shall carry out all electrical tests and ensure satisfactory resultsas set out in the ILE Code of Practice for Electrical Safety.

8 Where an existing installation has been extended the relevant parts of theexisting system and equipment earthing shall be inspected and tested forcompliance with the IEE Wiring Regulations.

9 A completion certificate as detailed in the IEE Wiring Regulations shall beissued following the inspection and testing of the installation and any correctiveaction found necessary.

12.3.2 Temporary Lighting

1 Where the existing installation is to be disconnected during the Contract Period,temporary lighting shall be provided.

2 At no time shall design road lighting standards be lower than those existingprior to the start of the Contract.

3 Any form of temporary lighting & lighting levels must be approved by theEngineer.

4 Temporary lighting shall not be removed or disconnected until the permanentinstallation has been inspected and approved by the Engineer and has beenenergised.

12.3.3 Electricity Supply

1 Lunminaires and equipment shall be suitable for use on a three phase and

neutral 415v 50hz supply.

12.3.4 Removal of Existing Installations

1 The Contractor shall obtain record drawings of the existing installation from theNEC before any work is carried out to the existing street lighting and provide theEngineer with one copy of the record drawings obtained.

2 Existing columns shall be removed under the supervision of NEC Street


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Rev.0 23/ 33

Lighting Section.

3 The Contractor shall carefully excavate existing material from around thecolumn (including concrete) and dismantle any existing equipment to beremoved and temporarily reinstate the excavation.

4 All lamps, luminaires and fittings shall be removed before excavating around thecolumns.

5 The equipment shall then be either re-erected as designated, or, if not to bereused, shall be removed to a designated location.

6 No existing highway or footway lighting shall be switched off, dismantled orremoved without the prior approval of the Engineer.

7 Adequate temporary highway or footway lighting to the satisfaction of theEngineer must be provided when it is necessary to remove existing lighting fromany area still open to vehicle or pedestrian traffic.

8 Where any existing illuminated or non-illuminated traffic signs are fixed tocolumns to be removed, they shall be refixed to the nearest replacementcolumn. If the nearest replacement column is more than 5 m away from thecolumn to be removed, poles and looped services shall be provided asnecessary. All existing loops shall be reconnected to the nearest replacementcolumn.

9 Existing cables shall be disconnected, insulated and covered to the satisfactionof NEC and the Engineer before removal of the column.

10 The column shall be supported by ropes at all times and excavated down to thebase taking care not to damage the electricity supply cables or any otheradjacent services. Under no circumstances shall the equipment be pushed orpulled straight before it has been fully excavated.

11 The column shall be lifted from the foundation by means of a crane and tackleapproved by both NEC and the Engineer.

12 All columns, codes, lamps and luminaires to be removed under the contractshall remain the property of NEC Street Lighting Section. Such items are to bedelivered to the NEC store. Proof of delivery shall be obtained by a signedreceipt from NEC witnessed by the Engineer.

12.3.5 Reuse of Existing Columns

1 Where existing columns are to be repositioned, the column bracket andpaintwork shall first be inspected for any damage. Shall damage be noted itshall immediately be reported to the Engineer.

2 The columns to be repositioned shall be carefully removed and stored for reuse.

3 Existing columns to be reinstalled shall be re-erected as described for new


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Rev.0 24/ 33

columns.

4 Existing columns, whether repositioned or not, shall be fitted with double polefuse isolators.

5 All removals shall be authorised in advance in writing by the concerned

authorities and the Engineer.

6 Before excavating around the column, any items of equipment identified by theEngineer shall be carefully removed and placed into storage as follows:

(a) after disconnection of the supply, carefully excavate around the column,first exposing all public utilities, underground services and otherinstallations, until it can safely be removed without damage to the columnor its protection system

(b) remove the foundation concrete and bracket arm before transporting tothe store

(c) remove all associated cabling where lighting columns are to be removed.

12.3.6 Wiring in Luminaires and Columns

1 Wiring between the terminal block in the luminaire and the components in thebase of the column or each unit shall be 2-core with integral earth wire to BS6004.

2 Wiring to photoelectric control units shall be 3-core with integral earth wire. Theyellow core shall be used for the switch wire. The 3-cores shall be used asfollows:

Red - PhaseBlue - Neutral

Yellow or White - Switch

3 All installation requirements described in the ILE Code of Practice Clause 11shall apply.

4 Internal wiring in the luminaires shall be 24/0.2 mm2

tinned copper conductor,suitably insulated with non-hygroscopic heat-resisting material, and luminairedesign shall be such as to facilitate wiring on site.

5 A 6.0 mm2

earth wire with camped tag bonded to earth lug on column and thecolumn door earth terminal shall be provided.

6 All cable routes shall be clear of control gear and limited to horizontal andvertical runs. Cables entering terminals shall show no bare wire nor shall theinsulation be taken into the electrical conducting part of the terminal. All cableshall be neatly bunched together and securely taped. .

7 Terminal blocks shall be clearly marked and the wiring shall be so arranged thatthe luminaire can be dismantled, for purposes of routine cleaning and lampreplacement, without any electrical wiring disconnections.


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Rev.0 25/ 33

8 A suitable means of clamping the cables and a substantial earthing terminalshall be provided in the luminaire.

12.3.7 Feeder Pillars

1 Clearances within the enclosure shall be sufficient to permit closing and locking

of the doors with switches inside in any position and also locked. Electricalclearances and creep distances between conductors and to earth shall not beless than 25 mm.

2 Testing of the completed distribution pillar shall be carried out as required by BS5486 Part 1 and the appropriate test certificates provided.

3 Access shall be by means of hinged doors or lift-off covers as designated or asdirected by the Engineer. Doors shall be fitted with locking bars to secure bothtop and bottom of each door. The means of locking shall be as designated.

4 Natural ventilation shall be provided to limit the temperature rise to the

manufacturers recommendations. Ventilation apertures shall not reduce the IPrating below designated rating and shall be screened to prevent entry of vermin.Where specified, air inlets and outlets shall be provided with dust filters.

5 Pillars shall be finished in the designated colour or as directed by the Engineer.

6 All pillars shall be fitted with removable lifting devices mounted one at each endand as near as possible to the balance line.

7 Any equipment which is not stable on its own supports shall be fitted for transitand storage with returnable extension feet to provide stability. Any special toolsfor assembling or locking shall be supplied.

8 A data plate shall be fixed to the pillar detailing the following information:

(a) clients reference/serial number(b) year of manufacture(c) normal current rating of busbars(d) normal current rating of incoming unit(e) gross weight (kg), when fully equipped(f) manufacturer's name and reference number.

9 The gross weight shall also be stencilled externally. Detailed distribution boardschedules within feeder pillars shall be provided. Feeder pillars shall be fittedwith a backboard together with distribution fuse board (with integral 100 A

isolator) and cable chamber. Engraved black on white labels shall be providedand fixed to the pillar with self-tapping screws.

10 A separated dedicated earth terminal block shall be fitted to the backboardwithin the base compartment of columns or posts. This shall be fittedirrespective of any other terminals available. Crimped connections shall be usedwherever possible. The dedicated earth terminal block shall be connected to theNEC (EN) earth terminal. For circuit conductors in the range of 16 mm2 to 35mm2, the circuit protective conductor shall have a cross-sectional area not less


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Rev.0 26/ 33

than 16 mm2 copper equivalent. The metal door of the base compartment ofmetallic columns or of the door and frame to feeder pillars shall be earthbonded. Nowhere shall metallic columns, posts, feeder pillars, or conduits berelied upon as the sole earth path. An earth spike shall be connected to eachhigh mast and to the further most column in each run of 12 m columns.

12.3.8 Cable Installation

1 The installation of all cables shall be carried out in accordance with part 6 ofsection 21 of Construction Specification

2 The type, manufacture and method of joint shall be approved by the Engineerbefore the work begins.

3 Cables shall only be handled when the ambient temperature in the area of thecables is above the minimum recommended by the manufacturer.

4 Cables shall be offered for inspection immediately after installation and before

any coverings are applied.

5 Cables shall be handled, terminated and installed in accordance with the cablemanufacturers recommendations. The technical advice of the manufacturersspecialists shall be followed if any special conditions or unusual circumstancesapply.

6 Cables shall only be handled when the ambient temperature in the area of thecables is above the minimum recommended by the manufacturer.

7 Cables shall be offered for inspection immediately after installation and beforeany coverings are applied.

8 Cables shall be handled, terminated and installed in accordance with the cablemanufacturers recommendations. The technical advice of the manufacturersspecialists shall be followed if any special conditions or unusual circumstancesapply.

9 Once a cable has been drawn off the drum, it shall immediately be laid inposition. No cable shall be left lying on the surface after removal from the drumfor more than the minimum practicable time.

10 Once a cable has been drawn off the drum, it shall immediately be laid inposition. No cable shall be left lying on the surface after removal from the drumfor more than the minimum practicable time.

11 Cable joining and sealing compounds shall be of a type approved by the cablemanufacturer. A tropical grade compound shall be used in locations where thenormal ambient temperature is likely to exceed 30 C.

12 Solderless cable sockets and ferrules for use with aluminium conductors, ifrequired, shall be made from electrical quality aluminium.

13 All solderless cable sockets and ferrules shall be installed using clamping tools


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Rev.0 27/ 33

of the same manufacture, strictly in accordance with the manufacturersrecommendations. The completed connections shall, in every case, meet theperformance requirements of BS 4579.

14 Cable joint boxes shall be of polycarbonate or similar transparent material withhigh impact resistance. The type and manufacture shall be to the approval of

the Engineer.

15 The joint filling compound shall be of the cold-pour resin type and shall bepolyurethane or epoxy resin and shall not contain filler material other than thatrequired to improve the characteristics of the compound. The resin fitting shallnot be inserted into the joint box until the joint has been inspected andapproved by the Engineer.

16 For straight through joints (or combined straight and tee joints) connection ofcores shall be by the compression method only.

17 For tee joints (or branch joints) connection of service cable to continuous main

cable cores shall be by means of clamps with screws except that the screwsshall not bear on the cable cores.

18 A copper earth bond shall be provided through the joint of fault carryingcapacity equal to the circuit protective conductor.

19 The total resistance of the earth path through the joint shall be not more thanthat of an equal length of the earth conductor of the un-jointed cable.

20 Where tee joints are indicated, the cable shall be laid so that joint positionsbetween drum lengths coincide with tee joint positions.

21 All tee and other branching joints shall be made with the main cable unbroken,except in the case where a separate straight through joint would otherwise berequired immediately adjacent to a branching joints.

22 Cables in straight through joints and, where the procedure is allowable underthe preceding clause, main cables in tee and other branching joints shall be

jointed core-to-core without crossing.

23 Approved safety precautions shall be taken when any work is to be done on anexisting cable.

24 Cabling will be looped into each column by means of an approved street lightingcut-out.

25 Intermediate joints will only be permitted where designated or where the lengthof cable recorded is in excess of the length obtainable in one piece from thecable manufacturer.

26 All joints shall be shown on the installation drawings.

27 Intermediate joints in polymeric insulated cables shall be made using materialsand methods approved by the cable manufacturer for the situation.


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Rev.0 28/ 33

28 Unless otherwise designated, cable glands shall be of brass and comply withBS 6121 where applicable, and shall be of a design appropriate to the type ofcable being terminated.

29 Cable glands for use with aluminium strip or aluminium wire armoured cablesshall be of tin nickel plated brass. Alternatively, they may be of aluminium

provided that this will not be incompatible with other materials with which it maybe in contact.

30 Glands for cables with metallic inner sheaths shall incorporate a bondingconnection.

31 Except where it is impracticable to do so, the cable cores shall be taken throughthe terminating box directly to the terminals of the equipment, without crosses,and shall be made off with sweated cast brass cable sockets, or an approvedtype of hydraulically crimped socket.

32 All cable sealing boxes shall be marked on the outside with 15 mm diameter

painted discs, in the appropriate colours, to indicate the disposition of the phaseand neutral conductors within them.

33 Compression glands installed externally shall be classified IP66 and beprovided with closefitting PVC shrouds.

34 In addition to the requirements of the Conditions of Contract, all testing andcommissioning shall be carried out according to the requirements of therelevant BS, CP and IEE Standards or other standards and regulations as maybe stated or implied in this Part.

35 Each completed system with the installation shall be tested as a whole underoperating conditions to ensure that each component functions correctly inconjunction with the rest of the installation.

36 The Contractor shall afford access at all times to the NEC to enable them toinspect work during and after erection and to be present at all tests.

37 Upon completion of laying and terminating underground cable runs, theContractor, in the presence of the Engineer or his duly authorisedrepresentative, shall carry out pressure tests in accordance with the relevantBritish Standards. The Contractor shall provide all apparatus and labourrequired for such tests and within a reasonable time thereafter shall present theEngineer with certificates witnessed by the Engineer.

38 Terminations for armoured cable shall incorporate a method of rating off the

armour which ensures a permanent earth bond between the cables terminatedto the satisfaction of the Engineer. The cable armour shall be bonded to theearth terminal block in each column.

39 As soon as is practicable after the completion of installation and jointing of thedesignated cables, or of any useable group of such cables, the tests describedbelow, together with such other tests and measurements to prove compliancewith this Part shall be made.


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Rev.0 29/ 33

40 An insulation tester shall be used to measure the insulation resistance betweeneach conductor and the remaining conductors and between each conductor andthe metallic sheath (if any) and armouring. The test voltage to be applied shallbe at least 1000 V.

41 The above tests shall be carried out both before and after any pressure tests

and the insulation resistance shall not be less than the figures in the appropriateBS.

42 A voltage test of 15 minutes duration shall be applied in accordance with BS5467 Appendix 88, BS 6622 Appendix C8 or BS 6346 Table 5, as applicable.

43 Proposals for the appropriate test in respect of other types of cable shall besubmitted for approval.

44 An earth continuity test shall be carried out to verify that the cable armouringand metal sheath, if any, have been properly bonded to earth.

45 Phase rotation and phase correspondence shall be tested to prove that thecables have been correctly connected.

46 Where a new cable has been jointed to an existing cable, the voltage testdesignated above may be carried out at a reduced voltage if the existing cablehas been in service for more than five years. In such a case the test voltageshall be determined by applying a factor K to the value given in the appropriateBritish Standard as referred to above, and the value of K shall be as given inthe following table:

Table 12.5Age of Cable and K Value

Age of existing cable in years K

0 - 5 1.05 - 10 0.910 - 15 0.815 - 20 0.720 - 25 0.625 - 30 0.5

47 Trench making, duct laying, backfilling and similar operations shall be inaccordance with the requirements of BS 7671 and the local authorities orSection 19 Part 3 which ever is more stringent. The following paragraphs are for

those aspects which apply additionally to cable, installations markers, coversand related items.

48 Marker posts and slabs shall be reinforced concrete or steel or heavy-dutyplastic of an approved type suitable for the duty.

49 Precast reinforced concrete or equal approved marker posts shall be installed atintervals of not more than 50 m along all underground cable routes, at all jointspositions, at all changes of direction and at both ends of road crossings, except


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Rev.0 30/ 33

where such posts are likely to cause an obstruction to vehicles or pedestrians orto be liable to damage. In such cases, marker slabs shall be used.

50 Marker posts and slabs shall bear the following inscriptions in clearly legiblelettering in both English and Arabic:

(a) for HV cable routes, 'High Voltage Cables'(b) for LV cable routes, 'Electric Cables'(c) for joint positions, 'Electric Cable Joint.

51 All cables not in ducts and where designated shall be protected by a continuouslayer of proprietary interlocking concrete or earthenware or plastic cable coversof such a width as will extend for at least 50 mm on each side of the cable.

52 All cable covers shall comply with the impact requirements of BS 2484.Concrete cable covers, if more than 300 mm in length, shall be suitablyreinforced. All cable covers shall bear on their upper surface a permanentwarning legend.

53 All cable covers shall be placed so that the underside is not less than 100 mmnor more than 150 mm above the top of the cable.

54 Cables buffed direct in the ground shall be indicated by a continuous strip ofbrightly coloured plastic tape. The plastic marker tape shall have black letterson yellow in English and Arabic stating "Caution Buried Electric Cable".

55 Where HV and LV cables run in the same cable trench, the HV cables shall beprotected by an independent run of cable covers.

56 Unless otherwise designated, and except where cables enter buildings or

traverse railways or roads or other paved areas likely to be subject to vehiculartraffic, underground cables shall be buried direct in the ground.

57 Cables between columns shall be buried at a minimum depth of 450 mm withintrenches as designated. The bottom of the trench shall be free from stones orsimilar hard substances and shall be firm and of smooth contour. TheContractor shall provide and spread fine dune sand to a depth of 100 mm in thebottom of the trench to provide a uniform bed for the cables.

58 Unless otherwise designated, low-voltage cables placed in the same trenchshall be laid with a lateral spacing between the cables of 50 mm.

59 Unless otherwise designated, low-voltage cables placed in the same trench as

telephone or other communications cables shall be separated from them by atleast 300 mm.

60 Unless otherwise designated, high-voltage cables shall be separated from lowvoltage or telephone cables placed in the same trench by at least 300 mm.

61 All cables shall be placed at least 300 mm clear of all other services in anydirection.


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64 Cables shall be snaked from side to side of the trench for a distance of 3 m oneach side of buried joints to avoid any risk of mechanical tension in the joint,and for a distance of 3 m in advance of entries to draw pits, buildings, or otherfixed structures.

65 Before cable laying is begun, all cable trenches shall be drained, the bottoms

graded and tamped, and all loose stones and similar debris removed.

66 Where designated, cables shall be installed in two tiers in the same trench. Thefirst tier of cables shall be covered with sufficient salt-free sand or selected soil,well compacted in 75 mm layers to give a firm level bed for the second tierwhich shall placed not less than 300 mm above the tops of the cables in the firsttier. The second tier of cables shall be covered as described above.

67 Where two tiers of cables are laid in the same trench, the lower tier shall beinstalled at such a depth as will permit the upper tier to be installed at thedesignated depths.

68 Cables laid in trenches shall be covered with backfill and the appropriate cablecovers with the minimum of delay.

69 While the trench is being backfilled, all large or sharp stones or other debrisshall be removed from the fill material.

70 In paved areas, the backfill shall be well compacted up to the underside of theexisting paved construction (including sub-base). Above this level, temporaryreinstatement shall be of similar construction to the original.

12.3.9 Duct Installation

1 Where cables

(a) cross roads or other paved areas with vehicular access(b) cross unpaved areas regularly used by vehicles(c) enter buildings(d) pass through corrosive soils.

or elsewhere as designated, they shall be drawn into underground pipe ducts.

2 A steel draw wire or nylon or polypropylene cord shall be inserted in each ductrun immediately after its installation. A 2 m surplus shall be left at each end ofeach run, neatly coiled and attached to a crossbar preventing the wire or cordfrom being drawn into the duct.

3 Underground pipe ducts shall be one of the following:

(a) best quality salt-glazed stoneware pipes with proprietary self-aligningspigot and socket joints.

(b) heavy gauge unplasticised PVC conduits with tapered sleeve or spigotand socket joints

(c) best quality vitrified clay pipes to BS 65, with glazed internal surface anda proprietary self-aligning and self-sealing joint.


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Rev.0 32/ 33

4 All ducts shall have a nominal internal diameter of 100 mm unless designatedotherwise.

5 The internal diameter of ducts used to provide cable entries into buildings shallhave a space factor less than 25 %, unless otherwise designated.

6 All dual systems shall be installed so that no undue strain is placed on cableswhen pulled in. Cable manufacturers recommendations shall be followed.

7 All underground cable ducts shall, so far as possible, be run in straight lines.

8 Duct runs crossing roads shall be straight and, wherever possible,perpendicular to the axis of the road.

9 Except in the case of short isolated duct runs such as road crossings,underground cable duct runs shall terminate in draw pits.

10 Cable ducts passing under roads carrying heavy vehicles shall be completely

surrounded with lean mix concrete

11 Ducts shall be laid so as to drain naturally towards one or both ends, whereadequate provision for drainage shall be made. Adequate precautions shall betaken to prevent the cable duct system acting as a stormwater or groundwaterdrainage system. A minimum fall of 1 in 200 shall be provided for drainagepurposes.

12 Any work carried out requiring the use of split ducts shall be carried out in sucha manner as to preserve the withdrawability of the cables concerned.

13 Notwithstanding the type of duct to be used generally, cable ducts laid inground which is liable to subsidence shall be of heavy gauge PVC with spigotand socket joints, and shall be installed on a concrete bed as designatedabove, but without concrete surround.

14 If two or more cables are to be installed in the same duct, the aggregate of theircross-sectional areas shall not exceed 30 % of the cross-sectional area of theduct.

15 All trenches excavated for the laying of cable ducts shall be completelybackfilled and rammed before cable installation work begins.

16 Immediately following the installation of any duct run, the interior of the ductshall be thoroughly cleaned by twice drawing through the ducts a suitable brush

once in each direction. Following this, the ends of each run shall be sealed witha suitable hardwood or plastic sealing plug which shall be left in position untilcable laying is about to begin.

17 Before any cables are installed in the ducts, each duct shall be proved bydrawing through it a polished hardwood mandrel 300 mm long having sphericalends and a diameter 6 mm less than the nominal duct diameter.


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12.3.10 Performance Testing

1 A certificate of Initial Performance of Installation shall be issued when testshave been passed as follows:

(a) the initial photometric tests shall be made after the installation has been inoperation for between l00 and 150 h of lighting

(b) the location of test positions shall be distributed along the length of theinstallation and shall be as directed by the Engineer. All service teststhroughout the testing period shall be made at these positions.

2 Readings shall be taken with a portable calibrated luminance meter. Themeasurements shall be taken by a qualified lighting engineer and the accuracyof the meter shall conform with the requirements of BS 5489.

3 Measurement of the supply voltage at the column or post shall be taken at thetime of each test and the illumination measurement shall be adjusted for anyvariation from the declared value. Allowance shall be made for control gear tapsimmediately before the initial tests are made. The lamps and all components ofthe luminaire which may affect the optical performance shall be cleaned andcorrectly adjusted.

4 All photometric testing shall be witnessed by the Engineer, unless otherwisenotified in writing. A minimum of 7-days notice shall be given to the Engineerbefore testing begins. After testing the certificates shall be submitted to theEngineer for approval.

END OF PART