METAR Cable Management Systems | Page 42

METAR LADDER Closed Covers METAR LADDER Peaked Covers METAR TECHNICAL DATA Straight Ladder Closed Cover This compilation of technical information is intended to supply essential details relating to the METAR Cable Ladder System. This will ensure that the specified cable ladder installation has suitable strength & rigidity to provide reliable support at minimum installed cost. Closed covers fit directly onto the side walls of the METAR Ladder & fittings to provide mechanical protection and shielding for cables and other equipment within the cable space. Closed covers of widths of 450mm and above are supplied with Bracing Kits (CBK) (see Bracing Kit Section). Closed Covers are punched with centreline slots to provide for water drainage. Peaked Covers are closed covers which are formed into a peak with an overall height of 50mm to shed sand, snow, water etc. Our Design Team is available to answer any questions relating to particula r site requirements which may not be answered in the following sections. Louvered Covers Contents Louvered Covers are similar to closed covers but with the addition of louvres for improved air flow through the cable space. Louvered covers are particularly useful where heavy duty power cables are being used. Most traditional cable management systems offer a raised cover for ventilation. 1.0 Metar Cable Ladder General Information Conventional raised covers have a number of considerations to be taken into account before installing them. First of which is that the cover will be susceptible to being lifted off in excessive winds, also the extra brackets and fixings will add to the installation time of each cover. Raised covers loading performance is far less than the loading performance of a close fitting louvered cover and due to the cover only being supported locally at the fixing point the raised cover is susceptible to sagging which will allow water and debris to build up. Louvered Covers of widths of 450mm and above are supplied with Bracing Kits (CBK) (see Bracing Kit Section). 1.1 Slot Patterns 1.2 Standard Material Gauges 1.3 Free Base Area 1.4 Cross-Sectional Area 1.5 Speedway Cable Ladder Specification Straight Ladder Louvre Cover Fitting to Fitting Cover When joining two abutting cable ladder fittings with a Fitting to Fitting Coupler (FFC) a 200mm gap is created in the cover span. To ensure complete mechanical and environmental protection of the cables, a Fitting to Fitting Cover is required. Fitting to Fitting Covers will be fixed directly to the adjoining covers and will ensure complete protection of cables within the span. 37 3.0 Loading Information 3.1 Dead Loads 3.2 Point Loads 3.3 Load Deflection Tables 2 0 Installation 2.1 Loads 2.2 Support Spacing 2.3 Locations of Couplers 2.4 Support Locations for Speedway Fittings 2.4.1 Speedway Flat Elbows 2.4.2 Speedway Inside & Outside Risers 2.4.3 Speedway Equal & Unequal Tees 2.4.4 Speedway Crosses 2.4.5 Speedway Reducers 2.5 Loading of Supports 2.6 Electrical Continuity Characteristics 2.7 Electromagnetic Compatibility (EMC) 2.8 Assembly Recommendations 38