vault backup: 2025-10-07 16:32:57
This commit is contained in:
@@ -0,0 +1,171 @@
|
||||
---
|
||||
id:
|
||||
aliases:
|
||||
- nec-314
|
||||
tags:
|
||||
- authorship/other
|
||||
- destiny/uncertain
|
||||
- status/incomplete
|
||||
- topic/electrical
|
||||
- type/encyclopedia
|
||||
---
|
||||
# Article 314 Outlet, Device, Pull, and Junction Boxes; Conduit Bodies; Fittings; and Handhole Enclosures
|
||||
|
||||
## Part I. Scope and General
|
||||
|
||||
<!-- TODO: TEXT OMITTED -->
|
||||
|
||||
## Part II. Installation
|
||||
|
||||
<!-- TODO: TEXT OMITTED -->
|
||||
|
||||
### 314.28 Pull and Junction Boxes and Conduit Bodies.
|
||||
|
||||
Boxes and conduit bodies used as pull or junction boxes
|
||||
shall comply with 314.28(A) through (E).
|
||||
|
||||
> [!exception]
|
||||
> Terminal housings supplied with motors shall comply with
|
||||
> the provisions of 430.12.
|
||||
|
||||
#### (A) Minimum Size.
|
||||
|
||||
For raceways containing conductors of 4 AWG or larger that are required to be insulated,
|
||||
and for cables containing conductors of 4 AWG or larger,
|
||||
the minimum dimensions of pull or junction boxes installed in a raceway or cable run
|
||||
shall comply with 314.28(A)(1) through (A)(3).
|
||||
Where an enclosure dimension is to be calculated based on the diameter of entering raceways,
|
||||
the diameter shall be the metric designator (trade size)
|
||||
expressed in the units of measurement employed.
|
||||
|
||||
##### (1) Straight Pulls.
|
||||
|
||||
In straight pulls,
|
||||
the length of the box or conduit body
|
||||
shall not be less than eight times the metric designator (trade size)
|
||||
of the largest raceway.
|
||||
|
||||
##### (2) Angle or U Pulls, or Splices.
|
||||
|
||||
Where splices or where angle or U pulls are made,
|
||||
the distance between each raceway entry inside the box or conduit body
|
||||
and the opposite wall of the box or conduit body
|
||||
shall not be less than six times the metric designator (trade size)
|
||||
of the largest raceway in a row.
|
||||
This distance shall be increased for additional entries
|
||||
by the amount of the sum of the diameters of all other raceway entries
|
||||
in the same row on the same wall of the box.
|
||||
Each row shall be calculated individually,
|
||||
and the single row that provides the maximum distance shall be used.
|
||||
|
||||
> [!exception]
|
||||
> Where a raceway or cable entry is in the wall of a box or conduit body
|
||||
> opposite a removable cover,
|
||||
> the distance from that wall to the cover
|
||||
> shall be permitted to comply with the distance required
|
||||
> for one wire per terminal in Table 312.6(A).
|
||||
|
||||
The distance between raceway entries enclosing the same conductor
|
||||
shall not be less than six times the metric designator (trade size)
|
||||
of the larger raceway.
|
||||
When transposing cable size into raceway size in 314.28(A)(1) and (A)(2),
|
||||
the minimum metric designator (trade size) raceway
|
||||
required for the number and size of conductors in the cable shall be used.
|
||||
|
||||
##### (3) Smaller Dimensions.
|
||||
|
||||
Listed boxes or listed conduit bodies
|
||||
of dimensions less than those required in 314.28(A)(1) and (A)(2)
|
||||
shall be permitted for installations of combinations of conductors
|
||||
that are less than the maximum conduit or tubing fill
|
||||
(of conduits or tubing being used)
|
||||
permitted by Table 1 of Chapter 9.
|
||||
Listed conduit bodies of dimensions less than those required in 314.28(A)(2),
|
||||
and having a radius of the curve to the centerline
|
||||
not less than that indicated in Table 2 of Chapter 9
|
||||
for one-shot and full-shoe benders,
|
||||
shall be permitted for installations
|
||||
of combinations of conductors
|
||||
permitted by Table 1 of Chapter 9.
|
||||
These conduit bodies shall be marked
|
||||
to show they have been specifically evaluated
|
||||
in accordance with this provision.
|
||||
Where the permitted combinations of conductors
|
||||
for which the box or conduit body has been listed
|
||||
are less than the maximum conduit or tubing fill permitted by Table 1 of Chapter 9,
|
||||
the box or conduit body shall be permanently marked
|
||||
with the maximum number and maximum size of conductors permitted.
|
||||
For other conductor sizes and combinations,
|
||||
the total cross-sectional area of the fill
|
||||
shall not exceed the cross-sectional area
|
||||
of the conductors specified in the marking,
|
||||
based on the type of conductor identified
|
||||
as part of the product listing.
|
||||
|
||||
> [!info]
|
||||
> Unless otherwise specified,
|
||||
> the applicable product standards evaluate the fill markings covered here
|
||||
> based on conductors with Type XHHW insulation.
|
||||
|
||||
#### (B) Conductors in Pull or Junction Boxes.
|
||||
|
||||
In pull boxes or junction boxes having any dimension over 1.8 m (6 ft),
|
||||
all conductors shall be cabled or racked up in an approved manner.
|
||||
|
||||
#### (C) Covers.
|
||||
|
||||
All pull boxes, junction boxes, and conduit bodies
|
||||
shall be provided with covers compatible with the box or conduit body construction
|
||||
and suitable for the conditions of use.
|
||||
Where used, metal covers shall comply with the grounding requirements of 250.110.
|
||||
|
||||
#### (D) Permanent Barriers.
|
||||
|
||||
Where permanent barriers are installed in a box,
|
||||
each section shall be considered as a separate box.
|
||||
|
||||
#### (E) Power Distribution Blocks.
|
||||
|
||||
Power distribution blocks shall be permitted
|
||||
in pull and junction boxes over 1650 cm3 (100 in.3)
|
||||
for connections of conductors where installed in boxes
|
||||
and where the installation complies with 314.28(E)(1) through (5).
|
||||
|
||||
> [!exception]
|
||||
> Equipment grounding terminal bars shall be permitted in smaller enclosures.
|
||||
|
||||
##### (1) Installation.
|
||||
|
||||
Power distribution blocks installed in boxes shall be listed.
|
||||
Power distribution blocks installed on the line side of the service equipment
|
||||
shall be listed and marked "suitable for use on the line side of service equipment" or equivalent.
|
||||
|
||||
##### (2) Size.
|
||||
|
||||
In addition to the overall size requirement in the first sentence of 314.28(A)(2),
|
||||
the power distribution block shall be installed in a box
|
||||
with dimensions not smaller than specified in the installation instructions
|
||||
of the power distribution block.
|
||||
|
||||
##### (3) Wire Bending Space.
|
||||
|
||||
Wire bending space at the terminals of power distribution blocks
|
||||
shall comply with 312.6.
|
||||
|
||||
##### (4) Live Parts.
|
||||
|
||||
Power distribution blocks shall not have uninsulated live parts exposed within a box,
|
||||
whether or not the box cover is installed.
|
||||
|
||||
##### (5) Through Conductors.
|
||||
|
||||
Where the pull or junction boxes are used for conductors
|
||||
that do not terminate on the power distribution block(s),
|
||||
the through conductors shall be arranged
|
||||
so the power distribution block terminals are unobstructed following installation.
|
||||
|
||||
## Part III. Construction Specifications
|
||||
|
||||
### 314.40 Metal Boxes, Conduit Bodies, and Fittings.
|
||||
|
||||
<!-- TODO: TEXT OMITTED -->
|
||||
Reference in New Issue
Block a user