For aluminum alloy busbar trunking, there is no need for bridging between each section; if the casing's joint surfaces are galvanized, bridging is unnecessary. The primary rulebook used in the safe use of cable trays is NEC Article 392. This is a description of how to select, install, and support these metal or plastic frames, on which electrical wires are installed. For further assistance, contact David Richmond (NEMA Senior Program Manager) at David. Cable tray systems are defined to include, but are not limited to straight sections of. 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. For licensed electricians, mastering these principles is essential.
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