Product Brochure

59
www.carlon.com
inside the box and beyond any cable clamps. Except as
provided in 300.15(C), the wiring shall be firmly
secured to the box or conduit body. Where raceway or
cable is installed with metal boxes or conduit bodies,
the raceway or cable shall be secured to such boxes
and conduit bodies.
(C) Nonmetallic Boxes and Conduit Bodies.
Nonmetallic Boxes and Conduit Bodies shall be
suitable for the lowest temperature-rated conductor
entering the box. Where nonmetallic boxes are used
with open wiring or concealed knob-and-tube wiring,
the conductors shall enter the box through individual
holes. Where flexible tubing is used to enclose the
conductors, the tubing shall extend from the last
insulating support to not less than 6 mm (
1
⁄4 in.)
inside the box inside the box and beyond any cable
clamp. Where nonmetallic-sheathed cable or multicon-
ductor Type UF cable is used, the sheath shall extend
not less than 6mm (
1
⁄4 in.) inside the box and beyond
any cable clamp. In all instances, all permitted wiring
methods shall be secured to the boxes.
Exception: Where nonmetallic-sheathed cable or
multiconductor Type UF cable is used with single gang
boxes not larger than a nominal size 57 mm  100 mm
(2
1
⁄
4 in.
 4 in.) mounted in walls or ceilings, and where
the cable is fastened within 200 mm (8 in.) of the box
measured along the sheath and where the sheath extends
through a cable knockout not less than 6 mm (
1
⁄4
in.),
securing the cable to the box shall not be required.
Multiple cable entries shall be permitted in a single cable
knockout opening.
(D) Conductors No. 4 or Larger. Installation shall
comply with Section 300.4(F).
FPN: See 110.12(A) for requirements on closing unused
cable and raceway knockout openings.
314.20 In Wall or Ceiling. In walls or ceilings with a
surface of concrete, tile, gypsum, plaster, or other noncom-
bustible material, boxes shall be installed so that the front
edge of the box will not be set back of the finished surface
more than 6 mm (
1
⁄4 in.).
In walls and ceilings constructed of wood or other
combustible surface material, boxes shall be flush with
the finished surface or project therefrom.