AUXILIARY GUTTERS

374-1. Use. Auxiliary gutters shall be permitted to supplement wiring spaces at meter centers, distribution centers, switchboards, and similar points of wiring systems and may enclose conductors or busbars but shall not be used to enclose switches, overcurrent devices, appliances, or other similar equipment. 374-2. Extension Beyond Equipment. An auxiliary gutter shall not extend a greater distance than 30 feet (9.14 m) beyond the equipment that it supplements. Exception: As provided in Section 620-35 for elevators. (FPN): For wireways, see Article 362. For busways, see Article 364. 374-3. Supports. Gutters shall be supported throughout their entire length at intervals not exceeding 5 feet (1.52 m). 374-4. Covers. Covers shall be securely fastened to the gutter. 374-5. Number of Conductors. Auxiliary gutters shall not contain more than thirty current-carrying conductors at any cross section. The sum of the cross-sectional areas of all contained conductors at any cross section of an auxiliary gutter shall not exceed 20 percent of the interior crosssectional area of the auxiliary gutter. Exception No. 1: As provided in Section 620-35 for elevators. Exception No. 2: 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. Exception No. 3: Where the correction factors specified in Article 310, Note 8(a) of Notes to Ampacity Tables of 0 to 2000 Volts are applied, there shall be no limit on the number of current-carrying conductors, but the sum of the cross-sectional area of all contained conductors at any cross section of the auxiliary gutter shall not exceed 20 percent of the interior cross-sectional area of the auxiliary gutter. (FPN): For conductor cross-sectional area, see Tables 5, 5A, 6, and 8 and the applicable Notes to Tables at the beginning of Chapter 9.