Cable tray installations

Many materials are subject to deterioration by ultraviolet light (UV). particularly many of the plastics and fiberglass materials. Fiberglass materials for outside use should be specified as UV-stabilized, and most plastics installed outdoors should be carbon-impregnated (black in color). It is particularly recommended that plastic cable ties, which secure cables in cable trays, be carbon-impregnated if installed outdoors. 

MG 2 Safety Standard for Construction and Guide for Selection, Installation, and Use of Electric Motors and Generators MG 10 Energy Guide for Selection and Use of Polyphase Motors VE 1 Cable Tray Systems... 

Material receipt Install transformers panels Install cable trays Lay cable Make connections Install fixtures Insulation - Equipment Material receipt Install Cover... 

The consequences on the installations were very limited striking the dome and the chilled water system DEG without loss of leaktightness, deformation of the cable tray without break or electricity fault. 

Figure 9.19 shows an installation at the Dow Stade membrane chlorine plant. It was built in 1996 by Techno Composites Domine Gmbh, using Bekaert profiles made with Derakane 440-40 epoxy vinyl ester resin. The installation includes stairwells, handrails, walkways cable trays and safety cages. GRP and pultruded profiles in particular were used for their resistance to the chemicals being handled - notably sodium hydroxide, sodium hypochlorite and brine. Their electrical resistance was also a factor in this electrochemical plant [11]. 

Install critical power, control, instrument, and alarm wiring and pneumatic tubing outside the fire-exposed envelope. Cable trays and conduit banks should be routed underground or on the upper levels of elevated pipe racks at least 30 feet above the ground and outside the drainage path of hydrocarbon spills. Install fire proofing of critical systems and equipment if they are inside the fire-exposed envelope. 

All cable trays were installed throughout the penthouse as well as all welding plugs, receptacles and lighting. The penthouse was operational and ready for rope up and final permanent services connection after the new headframe was constructed. 

Cable tray should be adequately supported during installation by brackets which are appropriate for the particular installation. The tray should be bolted to the brackets with round-headed bolts and nuts, with the round head inside the tray so that cables drawn along the tray are not damaged. 

Cable tray is a sheet-steel channel with multiple holes. The most common finish is hot-dipped galvanized but FVC-coated tray is also available. It is used extensively on large industrial and commercial installations for supporting Ml and SWA cables which are laid on the cable tray and secured with cable ties through the tray holes. 

Steel wire armoured PVC insulated cables are now extensively used on industrial installations and often laid on cable tray. This type of installation has the advantage of flexibility, allowing modifications to be made speedily as the need arises. The cable has a steel wire armouring giving mechanical protection... 

The cable may be laid directly in the ground, in ducts, on cable tray or clipped directly to a structure. It is not affected by water, oil or the cutting fluids used in engineering and can withstand very high temperatures or even fire. The cable diameter is small in relation to its current-carrying capacity and it should last indefinitely if correctly installed because it is made from inorganic materials. 

Steel wire armoured PVC insulated cables are now extensively used on industrial installations and often laid on cable tray. 

Although not as severe as those for outside plant cable, there are potential sources of stress for indoor cables that must be accounted for. In addition to stresses related to installation of the cable itself, inside plant cables must be flexible enough to support the tight bends experienced in cable trays and in the optical hardware which supports the overall intra-building cabling infrastructure. Indoor cables might... 

The fact that most indoor cable is placed by hand in cable trays or puUed for very short distances into duct, conduit, or the like, makes the installation aspect somewhat less critical of a consideration for such designs. In some tall buildings the cable might be placed vertically for several stories, but must then be supported periodically along its length to prevent excessive stress from being placed on it. 

When the cable is installed in raceways, cable trays, or secured to other cables, consideration should be given to movement of the existing cables. Although optical liber cable can be moved while in service without affecting fiber performance, it may warrant protection with conduit in places exposed to physical damage. 

An important aspect of overall system design is the physical construction of the existing system. Every system will have to be examined to determine if existing conduits, duct banks, and cable trays have sufficient space to handle the proposed cabling. This also includes future additions that may be required due to new service requirements. As previously discussed, the system designer must determine if there are sufficient fibers so that future cable installations are reduced or preferably eliminated. 

The short circuit can be caused by any conducting material. For example, in one recent case a number of electricians were installing a new cable on a cable tray adjacent to a 400 V distribution board. They were using single strands of wire to tie the cable to the tray, with the wire lengths typically in... 

Wiring should be installed in conduit, cable tray or wireway and not strung across light fixtures or pipes. 

In a typical process installation, the fiber may be run through conduit, exposed cable trays, indoor ductwork, and plenums. In these environments, the temperature can get below —30°C outside in the cable tray and over 60°C near the process pipes or in ductwork and plumbing. The cable may also see long-term UV exposure, rain, snow, and ice. In addition, the cable may be attacked by vermin and insects in some installations. 

Above the parallel running pipes, cross beams are often installed on which the cable trays are to be laid. 

Remove items that will not be required for extended periods from woik areas and put than in warehouse storage. Call for assistance. Temporary equipment required for special projects or support activities must be installed so that it will not constitute a hazard. A minimum clearance of 36 inches must be maintained around electrical power panels. Wiring and cables must be installed in a safe and orderly manner, preferably in cable trays. Machinery and possible contact points with electrical powa must have appropriate guarding. The controls for temporary equipment must be located to prevent inadvertent actuation or awkward manipulation. When heat-producing equipment must be installed, avoid accidental ignition of combustible... 

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