TIA-EIA-569-A-7-Cable_Tray.pdf

ANSI/TIA/EIA-569-A-7-2001

Approved: December 11, 2001

TIA/EIA

STANDARD

T

IA

/E

IA

-5

-A -7

Commercial Building Standard for Telecommunications Pathways and Spaces

Addendum 7

Cable Trays and Wireways

TIA/EIA-569-A-7

(Addendum No. 7 to TIA/EIA 569-A)

DECEMBER 2001

TELECOMMUNICATIONS INDUSTRY ASSOCIATION

The Telecommunications Industry Association Represents the Communications Sector of

NOTICE

TIA/EIA Engineering Standards and Publications are designed to serve the public interest through eliminating misunderstandings between manufacturers and purchasers, facilitating interchangeability and improvement of products, and assisting the purchaser in selecting and obtaining with minimum delay the proper product for his particular need. Existence of such Standards and Publications shall not in any respect preclude any member or nonmember of TIA/EIA from manufacturing or selling products not conforming to such Standards and Publications, nor shall the existence of such Standards and Publications preclude their voluntary use by those other than TIA/EIA members, whether the standard is to be used either domestically or internationally.

Standards and Publications are adopted by TIA/EIA in accordance with the American National Standards Institute (ANSI) patent policy. By such action, TIA/EIA does not assume any liability to any patent owner, nor does it assume any obligation whatever to parties adopting the Standard or Publication.

This Standard does not purport to address all safety problems associated with its use or all applicable regulatory requirements. It is the responsibility of the user of this Standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations before its use.

(From Standards Proposal No.3-2950-AD7, formulated under the cognizance of the TIA TR-42 Committee on User Premises Telecommunications Infrastructure.)

Published by

�TELECOMMUNICATIONS INDUSTRY ASSOCIATION 2001

Standards and Technology Department 2500 Wilson Boulevard Arlington, VA 22201

PRICE: Please refer to current Catalog of EIA ELECTRONIC INDUSTRIES ALLIANCE STANDARDS and ENGINEERING

PUBLICATIONS or call Global Engineering Documents, USA and Canada (1-800-854-7179) International (303-397-7956)

All rights reserved Printed in U.S.A.

PLEASE!

DON'T VIOLATE

THE

LAW!

This document is copyrighted by the TIA and may not be reproduced without permission.

Organizations may obtain permission to reproduce a limited number of copies through entering into a license agreement. For information, contact:

Global Engineering Documents 15 Inverness Way East Englewood, CO 80112-5704 or call U.S.A. and Canada 1-800-854-7179, International (303) 397-7956

NOTICE OF DISCLAIMER AND LIMITATION OF LIABILITY

The document to which this Notice is affixed has been prepared by one or more Engineering Committees of the Telecommunications Industry Association (“TIA”). TIA is not the author of the document contents, but publishes and claims copyright to the document pursuant to licenses and permission granted by the authors of the contents.

TIA Engineering Committees are expected to conduct their affairs in accordance with the TIA Engineering Manual (“Manual”), the current and predecessor versions of which are available at http://www.tiaonline.org/standards/sfg/engineering_manual.cfm. TIA’s function is to administer the process, but not the content, of document preparation in accordance with the Manual and, when appropriate, the policies and procedures of the American National Standards Institute (“ANSI”).

THE USE OR PRACTICE OF CONTENTS OF THIS DOCUMENT MAY INVOLVE THE

USE OF INTELLECTUAL PROPERTY RIGHTS (“IPR”), INCLUDING PENDING OR ISSUED

PATENTS, OR COPYRIGHTS, OWNED BY ONE OR MORE PARTIES. TIA MAKES NO

SEARCH OR INVESTIGATION FOR IPR. WHEN IPR CONSISTING OF PATENTS AND

PUBLISHED PATENT APPLICATIONS ARE CLAIMED AND CALLED TO TIA’S

ATTENTION, A STATEMENT FROM THE HOLDER THEREOF IS REQUESTED, ALL IN

ACCORDANCE WITH THE MANUAL. TIA TAKES NO POSITION WITH REFERENCE TO,

AND DISCLAIMS ANY OBLIGATION TO INVESTIGATE OR INQUIRE INTO, THE SCOPE

OR VALIDITY OF ANY CLAIMS OF IPR.

ALL WARRANTIES, EXPRESS OR IMPLIED, ARE DISCLAIMED, INCLUDING

WITHOUT LIMITATION, ANY AND ALL WARRANTIES CONCERNING THE ACCURACY

OF THE CONTENTS, ITS FITNESS OR APPROPRIATENESS FOR A PARTICULAR PURPOSE

OR USE, ITS MERCHANTABILITY AND ITS NON-INFRINGEMENT OF ANY THIRD

PARTY’S INTELLECTUAL PROPERTY RIGHTS. TIA EXPRESSLY DISCLAIMS ANY AND

ALL RESPONSIBILITIES FOR THE ACCURACY OF THE CONTENTS AND MAKES NO

REPRESENTATIONS OR WARRANTIES REGARDING THE CONTENT’S COMPLIANCE

WITH ANY APPLICABLE STATUTE, RULE OR REGULATION.

TIA SHALL NOT BE LIABLE FOR ANY AND ALL DAMAGES, DIRECT OR

INDIRECT, ARISING FROM OR RELATING TO ANY USE OF THE CONTENTS CONTAINED

HEREIN, INCLUDING WITHOUT LIMITATION ANY AND ALL INDIRECT, SPECIAL,

INCIDENTAL OR CONSEQUENTIAL DAMAGES (INCLUDING DAMAGES FOR LOSS OF

BUSINESS, LOSS OF PROFITS, LITIGATION, OR THE LIKE), WHETHER BASED UPON

BREACH OF CONTRACT, BREACH OF WARRANTY, TORT (INCLUDING NEGLIGENCE),

PRODUCT LIABILITY OR OTHERWISE, EVEN IF ADVISED OF THE POSSIBILITY OF

SUCH DAMAGES. THE FOREGOING NEGATION OF DAMAGES IS A FUNDAMENTAL

ELEMENT OF THE USE OF THE CONTENTS HEREOF, AND THESE CONTENTS WOULD

NOT BE PUBLISHED BY TIA WITHOUT SUCH LIMITATIONS.

http://www.tiaonline.org/standards/sfg/engineering_manual.cfm

ANSI/TIA/EIA-569-A-7

Addendum 7 to ANSI/TIA/EIA-569-A, 1

Cable Trays and Wireways

Table of Contents

1 INTRODUCTION

2 PURPOSE

3 SCOPE

4.5 Cable tray and cable runway

4.5.1 General

4.5.2 Location

4.5.3 General horizontal design information and cable fill

4.5.3.1 Cable trays

4.5.3.2 Cable runway

4.5.4 Support

4.5.5 Fittings, connectors and accessories

4.5.6 Installation

Table of Figures

Figure 1 – Ladder cable tray Figure 2 – Ventilated-bottom/ventilated-trough cable tray Figure 3 – Solid bottom/solid trough cable trays Figure 4 – Single rail cable trays Figure 5 – Wire cable tray Figure 6 – Cable runway Figure 7 – Cable tray with 5.5 mm (0.22 in) diameter cables at 50% calculated fill i

1 INTRODUCTION 1

Cable tray and cable runway systems are used within commercial buildings for pathways of telecommunications cabling. These systems are connected to the telecommunications room and may be routed throughout all parts of the building including access floors and ceiling pathways.

2 PURPOSE

The purpose of this Addendum is to replace subclause 4.5, Cable Trays and Wireways, of ANSI/TIA/EIA-569-A. Sub-clause 4.5 of ANSI/TIA/EIA-569-A is being modified to clarify industry issues with cable fill for cable tray systems. Additions and changes have been made to align with current terminology and applications. The numbering of subclauses after clause 3 are used to illustrate the replaced subclauses of ANSI/TIA/EIA-569-A.

3 SCOPE

This Addendum applies to cable trays and cable runways. The following provides criteria for cable fill, design criteria, and installation guidelines of cable trays and cable runways.

4.5 Cable tray and cable runway

4.5.1 General

Cable trays and cable runways are pre-fabricated structures for supporting and routing cables or conductors, that are pulled or laid in place after the pathway has been installed as a complete system.

The following are typical examples of the systems discussed in this section.

a) Ladder cable tray: A pre-fabricated structure consisting of side rails connected at the bottom by transverse members (rungs), for supporting and routing cables or conductors within the structure. See figure 1.

b) Ventilated-bottom or ventilated-trough cable tray: A cable tray consisting of either a bottom within two side rails, or a single-piece formed trough with ventilation openings in bottom. See figure 2.

c) Solid-bottom or solid-trough cable tray: A cable tray consisting of either a solid bottom within longitudinal side rails, or a single-piece formed trough. See figure 43.

d) Cable channel: A low-profile cable tray not exceeding 150 mm (6 in) wide constructed with a solid or ventilated bottom, used for small cable runs or cable drops from a larger cable tray.

e) Single-rail cable tray: An open cable tray consisting of a longitudinal rail with transversely connected members that project from one side (side-supported) or both sides (center-supported), which may have multiple tiers. See figure 4.

f) Wire cable tray: a cable tray manufactured from metal wire welded at all intersections and is formed to provide a channel for the cables. See figure 5.

g) Intermediate mesh cable support: A formed mesh material that provides an intermediate support between main support brackets provided at intervals of 1200 mm to 1500 mm (48 in to 60 in).

h) Cable runway: A pre-fabricated structure consisting of longitudinal rails connected at the top by transverse members (rungs) for supporting and routing cables or conductors on top of the structure. See figure 6.

Figure 1 – Ladder cable tray

Figure 2 – Ventilated-bottom/ventilated-trough cable tray

Figure 3 – Solid bottom/solid trough cable trays

Figure 4 – Single rail cable trays

Figure 5 – Wire cable tray

Figure 6 – Cable runway

4.5.2 Location 1

Cable support systems discussed here may be located below or above the ceiling or within an access floor in either plenum or non-plenum applications. Rules covering installations in both air plenums and non-plenum spaces are found in the applicable electrical and building codes.

4.5.3 General horizontal design information and cable fill

4.5.3.1 Cable trays

Cable trays shall be designed to accommodate a maximum calculated fill ratio of 50% to a maximum of 150 mm (6 in) inside depth. (See example 1). To allow room for future expansion, and to facilitate additions and removal of cables, a lower ratio is recommended during the initial design phase.

NOTE – A calculated fill ratio of 50% will physically fill the entire tray due to spaces between cables, and random placement. See figure 7.

Example 1 – What is the minimum width of a 75 mm (3 in.) deep cable tray supporting 1000 cables, each with a diameter of 5.5 mm (0.22 in)? This example uses metric measurement for demonstration purposes.

14.32 diametercablecableoneofArea 16

� � 2

746231000

14.35.51000 mmcablesofArea ��

� 18

%50 depthwidthfilltraycableofareaUsable �

� 20

7574623 2 mmwidthmm �

� 22

� �inmmtrayofwidthMinimum 265.678�

NOTE – Check widths and depths available from manufacturers

Figure 7 – Cable tray with 5.5 mm (0.22 in) diameter cables at 50% calculated fill

4.5.3.2 Cable runway 1

Cables installed on cable runway shall be stacked no higher than 150 mm (6 in). Retaining posts may be installed on runway to contain cables.

4.5.4 Support

The support span for cable support systems should be determined in accordance with the manufacturer’s maximum recommended load capacity for a given span. These systems may be supported by three basic methods: cantilever brackets from a wall, trapeze or individual rod supports from the ceiling, or directly from the floor. Cable tray supports should be located where practicable so that connections between sections of the tray fall between the support point and ¼ the distance of the span. A support should be placed within 600 mm (24 in) on each side of any connection to a bend, tee, or cross. See the NEMA-VE2 Metal Cable Tray Installation Guidelines for additional cable tray support and installation recommendations.

4.5.5 Fittings, connectors and accessories

Fittings and connectors are used to connect straight sections and change direction or size. Fittings include horizontal bends, vertical bends, reducers, crosses and tees. Connectors may include splice plates, splice clamps, and tee clamps. Accessories may include such items as covers, conduit adapters and barriers.

4.5.6 Installation

Cable trays shall be installed in accordance with the applicable electrical code and standards. The inside of the cable support system shall be free of burrs, sharp edges or projections that can damage cable insulation. Abrasive supports (e.g., threaded rod) installed within the cable fill area shall have that portion within the tray protected with a smooth, non-scratching covering so that cable can be pulled without physical damage. Installation of telecommunications cables shall not exceed the fill requirements stated in subclause 4.5.3. Openings in fire-rated walls, floors and ceilings shall be properly fire stopped (see annex A of ANSI/TIA/EIA-569-A). Cable trays and cable runways shall not be used as walkways or ladders.

Trays may be divided with a barrier to allow for physical separation between power and conductive telecommunications cables. Power and telecommunications cables shall be installed per electrical code. A minimum of 300 mm (12 in) access headroom shall be provided and maintained above a cable tray system or cable runway. Care shall be taken to ensure that other building components (e.g., air conditioning ducts) do not restrict access.