Complete separation is typically required, meaning low-voltage cables must not share the same raceway, cable tray, or enclosure as line voltage conductors. The primary mandate governing the co-location of high- and low-voltage wiring is physical separation, intended to prevent accidental contact between the two systems. Most low-voltage communication and control circuits fall under the Class 2 or Class 3 power-limited categories, which are. Why It Matters: Power conductors can induce noise into nearby limited energy and communications cabling, creating latency, packet loss, or disrupted signaling. Best Practice: Maintain TIA‑569‑E spacing between power and LE circuits. What are the NEC rules for mixing different voltage cables in the same cable tray? At times it becomes necessary, or even desirable, to route medium- or high-voltage cables (greater than 600V) in the same cable tray with cables rated 600V or less. This helps prevent the risks of electrical fires, shocks, and other potential issues.
[PDF Version]