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GENERAL ELECTRICAL SPECIFICATION
                                 Version 2014-2



                         The fixing centres of cables shall be in accordance with IET Regulations.

                         The cables shall be fixed to cable trays and the fabric of the building using one hole fixing
                         clips and brass screws/nut and bolt.

                         Where cables are buried within the fabric of the building they shall be enclosed within
                         heavy duty plastic conduit.
                         The internal radius of bends shall not be less than 6 times the overall diameter of the
                         cable.

                         Joints shall only be made at accessories e.g. alarm sounders, break glass units etc. No
                         joints being allowed in straight runs of cable.

                         Termination’s shall be made directly into accessory boxes using nylon compression gland.
                         All termination’s shall be fitted with a purpose made ferrule to protect the cable
                         insulation.

                         In wet situations, waterproof glands incorporating a sealing ring of polychloroprene (PCP)
                         shall be used.

                                                                        o
                         Flexible cables shall be to BS 6500 2000 rated to 150 C with a min CSA 1.5mm sq.
               2.9   MATERIALS AND INSTALLATION


               2.9.1  Steel Trunking

               2.9.1.1   Fitting

                         Cable trunking and fittings shall be manufactured from heavy duty gauge galvanised sheet
                         steel in accordance with BS 4678 : Part 1 (with amendments). Class 3 hot dip zinc coated
                         to BS 2989 : 1982.

                         The trunking system shall be mechanically and electrically continuous throughout and be
                         fully complete with overlapping lid, couplings, end caps, tinned copper earth continuity
                         links etc. Only purpose made fittings e.g. tees, bends, reducers shall be used.

                         Fire barriers shall be installed in the trunking as required in IET Regulation 527-02 and
                         527-04
                         Care shall be taken to ensure that all bends are of sufficient radius to permit compliance

                         with IET recommendations.
                         Trunking shall not be used as a protective conductor.

                         Flange connectors shall be used to terminate trunking into equipment or enclosures. The
                         opening into the equipment or enclosure shall be the same as the internal size of the
                         flanged connector and the edge of the opening  shall be bushed to avoid cable abrasion.





                                                      McDonalds Restaurants Ltd

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