What types of wires are used in cable trays

Cable trays commonly carry tray cables (TC), instrumentation tray cables (ITC), and metal-clad (MC) cables, designed for power, control, and communication applications.

Tray Cables (TC)

Tray Cable (TC) is a factory-assembled cable consisting of two or more insulated conductors, with or without grounding conductors, under a non-metallic jacket. TC cables are typically rated for 600 volts and are used in industrial power or control circuits where flame-retardant properties are required. They are suitable for installation in cable trays, raceways, and outdoor locations when supported by a messenger wire. TC cables can also be Type TC-ER (exposure rated), allowing short unsupported runs up to six feet between the tray and equipment, provided they are secured and protected against physical damage. TC cables are UL listed and may be used in hazardous locations such as Class 1, Division 2 areas .

Instrumentation Tray Cables (ITC)

Instrumentation Tray Cable (ITC) is designed for instrumentation and control applications. These cables can be shielded or unshielded, and may consist of multiple single conductors or twisted pairs, sometimes with metal armor for additional protection. ITC cables are used to transmit signals in industrial environments, providing reduced electrical interference and reliable performance in control and monitoring systems .

Metal-Clad (MC) Cables

Metal-Clad (MC) cables are another type of cable often installed in cable trays, particularly for 600-volt motor power circuits. MC cables feature a metallic armor over insulated conductors, offering mechanical protection and suitability for environments where physical damage is a concern. They are UL listed and can be used in both indoor and outdoor installations .

Other Considerations

Cable trays may also carry communication cables, fiber optic cables, and control cables, depending on the application. These cables are typically designed with robust jackets and insulation to withstand environmental factors such as heat, moisture, and mechanical stress. Shielded cables are often used in areas with high electrical noise to prevent interference. All cables installed in trays should comply with NEC Section 392 and be UL listed for tray use .

Summary

In summary, the most common types of cables used in cable trays include:

• Tray Cable (TC) – for power and control circuits, flame-retardant, 600V rated
• Instrumentation Tray Cable (ITC) – for signal and instrumentation, shielded or unshielded
• Metal-Clad (MC) Cable – armored for mechanical protection, suitable for power circuits
• Communication and Fiber Optic Cables – for data and signal transmission, often shielded These cables are selected based on voltage rating, environmental conditions, shielding requirements, and compliance with NEC and UL standards to ensure safe and reliable operation in industrial and commercial installations .