METAL WIREWAYS AND

NONMETALLIC WIREWAYS A. Metal Wireways 362-1. Definition. Wireways are sheet-metal troughs with hinged or removable covers for housing and protecting electric wires and cable and in which conductors are laid in place after the wireway has been installed as a complete system. 362-2. Use. Wireways shall be permitted only for exposed work. Wireways installed in wet locations shall be of raintight construction. Wireways shall not be installed (1) where subject to severe physical damage or corrosive vapor, nor (2) in any hazardous (classified) location except as permitted by Sections 501-4(b), 502-4(b), and 504-20. Exception: Wireways shall be permitted in concealed spaces in accordance with Section 640-4, Exception, item c. 362-3. Other Articles. Installations of wireways shall comply with the applicable provisions of Article 300. 362-4. Size of Conductors. No conductor larger than that for which the wireway is designed shall be installed in any wireway. 362-5. Number of Conductors. Wireways shall not contain more than thirty current-carrying conductors at any cross section. Conductors for signaling circuits or controller conductors between a motor and its starter and used only for starting duty shall not be considered as current-carrying conductors. The sum of cross-sectional areas of all contained conductors at any cross section of the wireway shall not exceed 20 percent of the interior crosssectional area of the wireway. The derating factors specified in Article 310, Note 8 (a) of Notes to Ampacity Tables of 0 to 2000 Volts shall not be applicable to the thirty current-carrying conductors at 20 percent fill specified above. Exception No. 1: Where the derating factors specified in Article 310, Note 8 (a) of Notes to Ampacity Tables of 0 to 2000 Volts are applied, the number of current-carrying conductors shall not be limited, but the sum of the cross-sectional areas of all contained conductors at any cross section of the wireway shall not exceed 20 percent of the interior cross-sectional area of the wireway.