GENERAL
Cable support systems shall be run level, straight and parallel with building lines to produce a tidy installation. Joints and accessories shall fit closely and shall be correctly matched. Provide all necessary hangers and brackets. Fixings shall be adequate for the items being fixed. The installation shall be in accordance with the manufacturer’s written recommendations. Supports and fixings shall comply with NZS 4219.
Care shall be taken to avoid bimetallic corrosion at fixings and joints. Fixings and fastenings shall be of a material appropriate to the parts being fixed, the loads imposed and the locations
involved. Bolts, screws, nuts, washers and other fixing components shall be zinc, chromium or cadmium plated.
Avoid sharp edges that may damage cables. Cut ends and cut-outs in cable support systems shall be neat and square. Cut edges shall be protected against corrosion. Cable support systems shall be complete with matching proprietary bonds, ties, reducers, expansion joints and jointing accessories which shall be employed as appropriate at junctions, changes of level, changes of direction, and changes of size. Metallic cable support systems shall be bonded to earth and shall be electrically continuous using, where necessary, earth continuity straps between sections.
Metal ties shall be used for all Fire Rated Cables.
CABLE LADDER
Cable ladder shall be constructed of medium duty, class A electro-galvanised to AS 1789 steel.
CABLE TRAY
Cable tray shall be constructed of medium duty, class A electro-galvanised to AS 1789 steel, rolled edge tray.
CABLE TRUNKING
Cable trunking shall be of the type and finish shown on the Drawings. Where not otherwise stated, cable trunking shall be of minimum thickness 1 mm sheet steel painted orange (BS 4800 colour No. 06E51). Vertical cable in trunking shall be fitted with insulated cable supports to support cables at maximum 2.5 metre intervals.
CONDUIT
Conduit shall be Electric Metallic Tubing (EMT) in plant rooms and service areas. The minimum size of conduit shall be 20 mm. Unless otherwise specified, conduit shall be one size larger than required by regulation for the number of conductors to be drawn in. Conduit shall be delivered to Site in manufacturers standard lengths each with a coupling on one end and thread protection on the other.
Conduit for any circuit shall be erected complete before any cable is drawn in. Conduits which penetrate walls or floors of fire resisting construction shall be treated in the following or equivalent approved manner. Seal all PVC conduit penetrations with firestop collars. Seal all steel conduit penetrations with PYROSAFE SVT universal bulkhead system and pack any gaps with FYREFYBA ceramic fibre. For small penetrations with gaps less than 10mm seal with fire resistant foaming sealant.