A separate EGC should be bonded to the cable tray with a bonding / grounding clamp. The EGC is the most important conductor in an electrical system as its function is electrical safety. Metallic cable tray systems can become energized under fault conditions, making an effective grounding. Power circuit grounding of cable trays is explained in CTI Technical Bulletins, Titles No. It is also covered in NEMA Standard VE-2. It involves connecting cable trays to the facility's grounding system, providing a low-impedance path for fault currents and protecting personnel. All metallic cable trays shall be grounded as required in Article 250. 3 (B) (1) through (B) (4) [300. Metal raceways, cable armor, and other metal enclosures must be.