To prevent loosening, regular inspections and maintenance are essential. It's also recommended to use anti-loosening mechanisms, such as lock washers or locking nuts, at critical joints to prevent future. The following pages address the 2014 National Electrical Code® requirements for cable tray systems as well as design solutions from practical experience. The information has been organized for use as a reference guide for both those unfamiliar and those experienced with cable tray. Nearly every. en completely installed, without damage either to conductors or structural system use maintain spacing or to keep cables in place when the tray is ect the minimum bend ra-dius for cables as they exit the bottom of the cable tray. Cable trays support cables across open spans in the same way that roadway bridges support traffic. Cable trays can provide a safe component of a power, low voltage. Cable tray failures can cause operational disruptions, equipment damage, and safety risks. This guide discusses common cable tray problems, from loosening and corrosion to grounding issues and installation errors, along. Quest offers couplers for joining all Quest Cable Trays. Color Length. Quest offers a coupler for tooless connection of angles.