Due to their exposure to the open air because of the cable trays, the wires contained within need a very durable outer covering. The regulations dictate that the cables must either be Type TC (also known as Tray Rated) or must be metal-armored (Type MC). This is a description of how to select, install, and support these metal or plastic frames, on which electrical wires are installed. You should consider it as a series of instructions that make the buildings resistant to. Installation of Cable in Cable Trays involves precise routing on support systems, NEC/IEC compliance, grounding, ampacity derating, bend radius control, segregation of services, fire safety, labeling, and reliable cable management for industrial and commercial facilities. The use of ladder-type. Answer: No. Well suited for power and large control cables. Cable tray is the preferred wiring method for industrial facilities, data centers, and large commercial buildings where routing dozens or. Ventilated troughs are excellent for smaller control and instrumentation cables that may sag between the rungs of a ladder tray.