Menu

Article 396

Messenger-Supported Wiring

Part I. General

  1. Scope. This article covers the use, installation, and construction specifications for messenger-supported wiring.
  2. Definitions.
image

N

Insulated Conductor. For the purposes of this article, an insu‐ lated conductor includes the following:

  1. Conductor types described in 310.104, and
  2. Overhead service conductors encased in a polymeric material that has been evaluated for the applied nominal voltage.

Informational Note: Evidence of evaluation for the applied nominal voltage can be given by certification that the conduc‐ tors have met the requirements of ICEA S-76-474-2011, Standard for Neutral Supported Power Cable Assemblies with Weather-Resistant Extruded Insulation Rated 600 Volts.

Messenger-Supported Wiring. An exposed wiring support system using a messenger wire to support insulated conductors by any one of the following:

  1. A messenger with rings and saddles for conductor support
  2. A messenger with a field-installed lashing material for conductor support
  3. Factory-assembled aerial cable
  4. Multiplex cables utilizing a bare conductor, factory assem‐ bled and twisted with one or more insulated conductors, such as duplex, triplex, or quadruplex type of construc‐ tion

396.10 ARTICLE 398 — OPEN WIRING ON INSULATORS

Part II. Installation

396.10 Uses Permitted.

  1. Cable Types. The cable types in Table 396.10(A) shall be permitted to be installed in messenger-supported wiring under the conditions described in the article or section referenced for each.
  2. In Industrial Establishments. In industrial establishments only, where conditions of maintenance and supervision ensure that only qualified persons service the installed messenger- supported wiring, the following shall be permitted:
    1. Any of the conductor types shown in Table 310.104(A) or Table 310.104(B)
    2. MV cable
    Where exposed to weather, conductors shall be listed for use in wet locations. Where exposed to direct rays of the sun, conductors or cables shall be sunlight resistant.
  3. Hazardous (Classified) Locations. Messenger-supported wiring shall be permitted to be used in hazardous (classified) locations where the contained cables and messenger-supported wiring are specifically permitted by other articles in this Code.

396.12 Uses Not Permitted. Messenger-supported wiring shall not be used in hoistways or where subject to physical damage.

396.30 Messenger.

  1. Support. The messenger shall be supported at dead ends and at intermediate locations so as to eliminate tension on the conductors. The conductors shall not be permitted to come into contact with the messenger supports or any structural members, walls, or pipes.
  2. Neutral Conductor. Where the messenger is used as a neutral conductor, it shall comply with the requirements of 225.4, 250.184(A), 250.184(B)(7), and 250.187(B).
  3. Equipment Grounding Conductor. Where the messenger is used as an equipment grounding conductor, it shall comply

Table 396.10(A) Cable Types

image
image

Cable Type Section Article

Medium-voltage cable 328

Metal-clad cable 330

with the requirements of 250.32(B), 250.118, 250.184(B)(8), and 250.187(D).

396.56 Conductor Splices and Taps. Conductor splices and taps made and insulated by approved methods shall be permit‐ ted in messenger-supported wiring.

396.60 Grounding. The messenger shall be grounded as required by 250.80 and 250.86 for enclosure grounding.

Last posts

Sidebar