I. General

(B) Adjustment Factors. The adjustment factors in

310.15(B)(2)(a) shall be applied only where the number
of current-carrying conductors, including neutral
conductors classified as current-carrying under the
provisions of 310.15(B)(4), exceeds 30. 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.

376.23 Insulated Conductors. Insulated conductors in

376.1 Scope. This article covers the use, installation,

and construction specifications for metal wireways and
associated fittings.

376.2 Definition.

Metal Wireways. Sheet metal troughs with hinged or removable covers for housing and protecting electrical wires and cable and in which conductors are laid in place after the wireway has been installed as a complete system.

II. Installation

376.10 Uses Permitted. The use of metal wireways shall be permitted in the following:

(1) For exposed work

(2) In concealed spaces as permitted in 376.10(4)

(3) In hazardous (classified) locations as permitted by

501.10(B) for Class I, Division 2 locations; 502.10(B)
for Class II, Division 2 locations; and 504.20 for
intrinsically safe wiring. Where installed in wet
locations, wireways shall be listed for the purpose.

(4) As extensions to pass transversely through walls if the length passing through the wall is unbroken. Access to the conductors shall be maintained on both sides of the wall.

376.12 Uses Not Permitted. Metal wireways shall not be used in the following:

(1) Where subject to severe physical damage

(2) Where subject to severe corrosive environments

376.21 Size of Conductors. No conductor larger than that for which the wireway is designed shall be installed in any wireway.

376.22 Number of Conductors and Ampacity. The num- ber of conductors and their ampacity shall comply with

376.22(A) and (B).

(A) Cross-Sectional Areas of Wireway. The sum of the cross-sectional areas of all contained conductors at any cross section of a wireway shall not exceed 20 percent of the interior cross-sectional area of the wireway.

stalled in a metallic wireway shall comply with
376.23(A)
and (B).

(A) Deflected Insulated Conductors. Where insulated conductors are deflected within a metallic wireway, either at the ends or where conduits, fittings, or other raceways or cables enter or leave the metallic wireway, or where the direction of the metallic wireway is deflected greater than 30 degrees, dimensions corresponding to one wire per terminal in Table

312.6(A) shall apply.

(B) Metallic Wireways Used as Pull Boxes. Where insulated conductors 4 AWG or larger are pulled through a wire-way, the distance between raceway and cable entries enclosing the same conductor shall not be less than that required by 314.28(A)(1) for straight pulls and

314.28(A)(2) for angle pulls. When transposing cable size
into raceway size, the minimum metric designator (trade
size) raceway required for the number and size of
conductors in the cable shall be used.

376.30 Securing and Supporting. Metal wireways shall be supported in accordance with 376.30(A) and (B).

(A) Horizontal Support. Wireways shall be supported where run horizontally at each end and at intervals not to exceed 1.5 m (5 ft) or for individual lengths longer than

1.5 m (5