Can Class 2 and Class 3 circuits share a cable tray?

Class 2 and Class 3 circuits cannot share a cable tray due to safety and performance standards set forth by the National Electrical Code (NEC) and other regulatory guidelines. Class 2 and Class 3 circuits are defined by their power limitations and are subject to different installation rules.

Class 2 circuits provide a low voltage and current that is safe to touch and typically used for communication systems, such as alarm systems or intercoms. Class 3 circuits, while also low voltage, may carry slightly higher currents. Sharing a cable tray could lead to potential interference, which could affect the performance and reliability of the circuits, as well as pose a risk of unintentional contact.

The NEC has specific requirements to ensure that different classes of circuits are adequately separated, providing a clear demarcation for safety and compliance. This separation helps to prevent issues related to grounding, signal integrity, and compliance with code requirements.