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Article 336

  1. Power and Control Tray Cable: Type TCPart I. General
    1. Scope. This article covers the use, installation, and construction specifications for power and control tray cable, Type TC.
    2. Definition.Power and Control Tray Cable, Type TC. A factory assembly of two or more insulated conductors, with or without associated bare or covered grounding conductors, under a nonmetallic jacket.imageN336.6 Listing Requirements. Type TC cables and associated fittings shall be listed.
      Part II. Installation336.10 Uses Permitted. Type TC cable shall be permitted to be used as follows:
    3. For power, lighting, control, and signal circuits.
    4. In cable trays, including those with mechanically discon‐ tinuous segments up to 300 mm (1 ft).
    5. In raceways.
    6. In outdoor locations supported by a messenger wire.
    7. For Class 1 circuits as permitted in Parts II and III of Article 725.
    8. For non–power-limited fire alarm circuits if conductors comply with the requirements of 760.49.
    9. Between a cable tray and the utilization equipment or device(s), provided all of the following apply:imageThe cable is Type TC-ER.The cable is installed ina.
      1. industrial establishmentswhere the conditions of maintenance and supervi‐ sion ensure that only qualified persons service the installation.
      2. The cable is continuously supported and protected against physical damage using mechanical protection such as struts, angles, or channels.
      3. The cable that complies with the crush and impact requirements of Type MC cable and is identified with the marking “TC–ER.”
      4. The cable is secured at intervals not exceeding 1.8 m (6 ft).
      5. 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 must be provided within the cable or, at the time of installation, one or more insulated conductors must 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 utilization 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.

  1. Where installed in wet locations, Type TC cable shall also be resistant to moisture and corrosive agents.
  2. In one- and two-family dwelling units, Type TC-ER cable containing both power and control conductors that is identified for pulling through structural members shall be permitted. Type TC-ER cable used as interior wiring shall be installed per the requirements of Part II of Arti‐ cle 334.Exception: Where used to connect a generator and associatedequipment having terminals rated 75°C (140°F) or higher, the cable shall not be limited in ampacity by 334.80 or 340.80.
    Informational Note No. 1: TC-ER cable that is suitablefor pulling through structural members is marked “JP.”
    Informational Note No. 2: See 725.136 for limitations on Class 2 or 3 circuits contained within the same cable withconductors of electric light, power, or Class 1 circuits.
  3. Direct buried, where identified for such use

Informational Note: See 310.15(A)(3) for temperature limita‐ tion of conductors.

336.12 ARTICLE 338 — SERVICE-ENTRANCE CABLE: TYPES SE AND USE

336.12 Uses Not Permitted. Type TC tray cable shall not be installed or used as follows:

  1. Installed where it will be exposed to physical damage
  2. Installed outside a raceway or cable tray system, except as permitted in 336.10(4), 336.10(7), 336.10(9), and 336.10(10)
  3. Used where exposed to direct rays of the sun, unless iden‐

336.24 Bending Radius. Bends in Type TC cable shall be

made so as not to damage the cable. For Type TC cable without metal shielding, the minimum bending radius shall be as follows:

  1. Four times the overall diameter for cables 25 mm (1 in.) or less in diameter
  2. Five times the overall diameter for cables larger than 25 mm (1 in.) but not more than 50 mm (2 in.) in diame‐ ter
  3. 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 diam‐ eter.

336.80 Ampacity. The ampacity of Type TC tray cable shall be determined in accordance with 392.80(A) for 14 AWG and larger conductors, in accordance with 402.5 for 18 AWG through 16 AWG conductors where installed in cable tray, and in accordance with 310.15 where installed in a raceway or as messenger-supported wiring.

Part III. Construction Specifications

336.100 Construction. A metallic sheath or armor as defined in 330.116 shall not be permitted either under or over the nonmetallic jacket. Metallic shield(s) shall be permitted over groups of conductors, under the outer jacket, or both.

336.104 Conductors. The insulated conductors of Type TC cables shall be in sizes 18 AWG to 1000 kcmil copper, nickel, or nickel-coated copper, and sizes 12 AWG through 1000 kcmil aluminum or copper-clad aluminum. Insulated conductors of sizes 14 AWG, and larger copper, nickel, or nickel-coated copper, and sizes 12 AWG through 1000 kcmil aluminum or copper-clad aluminum shall be one of the types listed in Table 310.104(A) or Table 310.104(B) that is suitable for branch circuit and feeder circuits or one that is identified for such use.

  1. Fire Alarm Systems. Where used for fire alarm systems, conductors shall also be in accordance with 760.49.
  2. Thermocouple Circuits. Conductors in Type TC cable used for thermocouple circuits in accordance with Part III of Article 725 shall also be permitted to be any of the materials used for thermocouple extension wire.
  3. Class 1 Circuit Conductors. Insulated conductors of 18 AWG and 16 AWG copper shall also be in accordance with 725.49.

336.116 Jacket. The outer jacket shall be a flame-retardant, nonmetallic material.

336.120 Marking. There shall be no voltage marking on a Type TC cable employing thermocouple extension wire.

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