Article 336 Power and Control Tray Cable: Type TC
- For power, lighting, control, and signal circuits.
- In cable trays, including those with mechanically discontinuous segments up to 300 mm (1 ft).
- In raceways.
- In outdoor locations supported by a messenger wire.
- For Class 1 circuits as permitted in Parts II and III of Article 725.
- For non-power-limited fire alarm circuits if conductors comply with the requirements of 760.49.
- Between a cable tray and the utilization equipment or device(s), provided all of the following apply:
- The cable is Type TC-ER.
- The cable is installed in industrial establishments where the conditions of maintenance and supervision ensure that only qualified persons service the installation.
- The cable is continuously supported and protected against physical damage using mechanical protection such as struts, angles, or channels.
- The cable complies with the crush and impact requirements of Type MC cable and is identified with the marking "TC-ER."
- The cable is secured at intervals not exceeding 1.8 m (6 ft).
- Equipment grounding for the utilization equipment is provided by an equipment grounding conductor within the cable. In cables containing conductors sized 6 AWG or smaller, the equipment grounding conductor shall be provided within the cable or, at the time of installation, one or more insulated conductors shall be permanently identified as an equipment grounding conductor in accordance with 250.119(B).
Exception to (7): Where not subject to physical damage, Type TC-ER shall be permitted to transition between cable trays and between cable trays and equipment or devices for a distance not to exceed 1.8 m (6 ft) without continuous support. The cable shall be mechanically supported where exiting the cable tray to ensure that the minimum bending radius is not exceeded.
- Type TC cable shall be resistant to moisture and corrosive agents where installed in wet locations.
- In one- and two-family dwelling units, Type TC-ER-JP cable containing both power and control conductors shall be permitted for branch circuits and feeders. Type TC-ER-JP cable used as interior wiring shall be installed per the requirements of Part II of Article 334 and where installed as exterior wiring shall be installed per the requirements of Part II of Article 340.
Informational Note: See 725.136 for limitations on Class 2 or 3 circuits contained within the same cable with conductors of electric light, power, or Class 1 circuits.
- Direct buried, where identified for such use.
- In hazardous (classified) locations where specifically permitted by other articles in this Code.
Informational Note: See 310.14(A)(3) for temperature limitation of conductors.
- Four times the overall diameter for cables 25 mm (1 in.) or less in diameter
- Five times the overall diameter for cables larger than 25 mm (1 in.) but not more than 50 mm (2 in.) in diameter
- Six times the overall diameter for cables larger than 50 mm (2 in.) in diameter
Type TC cables with metallic shielding shall have a minimum bending radius of not less than 12 times the cable overall diameter.
For control and signal conductors, the minimum conductor sizes shall be 18 AWG copper, nickel, or nickel-coated copper, 14 AWG copper-clad aluminum, and 12 AWG aluminum.
- The overall nonmetallic jacket shall be suitable for the environment.
- The overall cable construction shall be essentially circular in cross-section.
- The overall nonmetallic jacket shall be continuous and gas/vapor tight.
- For construction greater than 25.4 mm (1 in.) in diameter, the following shall apply:
- The equipment grounding conductor shall be bare.
- A metallic shield shall be included over all conductors under the outer jacket.