Where cable tray systems contain only signal and communication circuits that operate at low energy levels, power grounding per NEC Section 318-7 is not appropriate, but cable tray grounding for lightning protection, noise, and electromagnetic interference is necessary. Cable tray may be used as the Equipment Grounding Conductor (EGC) in any installation where qualified persons will service the installed cable tray system. These definitions are NEC terminology and apply to power system grounding. 8, 11, and 12, and the. Grounding in cable trays is an important practice to increase electrical safety and prevent hazards in case of faults. A cable tray grounding is best inspected by searching cable tray sections with bonding jumpers (the thick green or copper wires connecting various sections of the tray) and checking them with a device known as a multimeter.
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