This guide discusses common cable tray problems, from loosening and corrosion to grounding issues and installation errors, along with strategies for prevention and resolution. Understanding the root causes of cable tray failures is the first step toward ensuring system. Cable sag results from incorrect spacing of cable tray supports or from employing the incorrect tray type that is, light-duty perforated trays in high-load applications. Complicating the problem are overloaded trays and large unsupported spans. Sagging causes tension at connection points. However, improper installation. Answer: No. NEC section 300-8 does not permit any tube, pipe, or equal for water, air gas, drainage, steam, or any service other than electrical in raceways or cable trays containing. At first, our practice in power stations, was running instrument cables on separate cable trays solid bottom and covered usually of steel [or aluminum] at the uppermost position, above the low voltage power cable trays-one feet distance- and at the lower level medium voltage shielded cables- shield. Electrical noise is the result of more or less random electrical signals getting coupled into circuits where they are unwanted, i. Noise occurs on both power and signal circuits, but generally speaking, it becomes a problem when it gets on signal.
