ipc-a-640 acceptance requirements for optical fiber, optical cable, and hybrid wiring harness ...

142 Pages·2016·3.96 MB·English

IPC-A-640_ 11-04-2016

IPC-A-640

ACCEPTANCE REQUIREMENTS
FOR OPTICAL FIBER, OPTICAL CABLE,
AND HYBRID WIRING HARNESS
ASSEMBLIES

7-31M Fiber Optic Task Group

11/04/2016
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HIEARARCHY OF IPC DESIGN SPECIFICATIONS

(IPC-A-640 SERIES)

Figure 1 - IPC-A-640 Structure

FOREWORD

This standard provides information on the design and acceptance requirements for optical fiber, optical
cable and hybrid wiring harness to the extent that they can be applied to the broad spectrum of optical
cable and wiring harness design. It is therefore crucial that decisions concerning the choice of product
classification, fiber technology, connectorization requirements, and performance and reliability
requirements be made as early as possible. <45E>

As optical wiring and connector technology changes, specific requirements will be updated or new
requirements added to the document set.

The IPC invites input on the effectiveness of the documentation and encourages User response through
completion of ‘‘Suggestions for Improvement’’ forms located at the end of each document
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CONTENTS

1 GENERAL .................................................................................................................................. 9
1.1 Scope .......................................................................................................................................... 9
1.2 Purpose ....................................................................................................................................... 9
1.3 Classification ............................................................................................................................. 10
1.4 Definition of Requirements ....................................................................................................... 10
1.5 Requirement Format (N/A/D) ................................................................................................... 10
1.5.1 Requirements Flowdown .......................................................................................................... 11
1.5.2 Notes / Italicized Text................................................................................................................ 11
1.5.3 Commercial Off-The-Shelf (COTS) ............................................................................................ 11
1.5.4 Existing or Previously Approved Designs ................................................................................. 11
1.5.5 Line Drawings and Illustrations ................................................................................................. 11
1.6 Measurement Units and Applications ....................................................................................... 11
1.7 Definition of Terms .................................................................................................................... 12
1.8 Engineering Documentation ..................................................................................................... 12
1.9 Order of Precedence................................................................................................................. 12
1.9.1 Conflict ...................................................................................................................................... 12
1.9.2 Clause References ................................................................................................................... 13
1.10 Appendices A – C ..................................................................................................................... 13
1.11 Approval of Departures From Standards and Requirements ................................................... 13
1.12 Personnel Proficiency ............................................................................................................... 13
1.13 Facilities .................................................................................................................................... 13
1.13.1 Temperature ............................................................................................................................. 14
1.13.2 Humidity .................................................................................................................................... 14
1.13.3 Process Control / Test .............................................................................................................. 14
1.13.4 Positive Pressure ...................................................................................................................... 14
1.13.5 Personnel Behavior ................................................................................................................... 14
1.13.6 Field Assembly Operations ....................................................................................................... 14
1.14 Foreign Object Debris (FOD) Control Plan ............................................................................... 14
1.15 Safety ........................................................................................................................................ 15
1.15.1 Chemicals ................................................................................................................................. 15
1.15.1.1 Epoxies / Adhesives .................................................................................................................. 15
1.15.1.2 Toxic Products and Formulations ............................................................................................. 15
1.15.1.3 Protection From Bare Fibers ..................................................................................................... 15
1.15.2 Eye Safety – Energized Source Concern ................................................................................. 16
1.16 Tools and Equipment ................................................................................................................ 16
1.16.1 Control ...................................................................................................................................... 16
1.16.2 Calibration ................................................................................................................................. 17
1.17 Electrostatic Discharge (ESD) Protection ................................................................................. 17
1.18 Contamination ........................................................................................................................... 17
1.19 Rework / Repair ........................................................................................................................ 17
1.20 Statistical Process Control (SPC) ............................................................................................. 18

2 APPLICABLE DOCUMENTS ................................................................................................... 19
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2.1 Aerospace ................................................................................................................................. 19
2.2 Commercial ............................................................................................................................... 19
2.3 Federal ...................................................................................................................................... 19
2.4 Military Handbooks ................................................................................................................... 19
2.5 Military Specifications ............................................................................................................... 19
2.6 Reference ................................................................................................................................. 19

3 ASSEMBLY .............................................................................................................................. 23
3.1 Optical Fiber End Preparation .................................................................................................. 23
3.1.1 Procedures – Optical Fiber Processing .................................................................................... 23
3.1.1.1 Preconditioning ......................................................................................................................... 23
3.1.1.2 Cables ....................................................................................................................................... 23
3.1.1.3 Cleaved / Bare Fiber ................................................................................................................. 23
3.1.1.4 Removal of Outer Jacket(s) ...................................................................................................... 23
3.1.1.4.1 Chemical Strippers .................................................................................................................... 23
3.1.1.5 Adhesives ................................................................................................................................. 24
3.1.1.6 Waste Disposal ......................................................................................................................... 24
3.1.1.7 Inspection .................................................................................................................................. 24
3.1.1.8 End Face Finishing ................................................................................................................... 24
3.1.1.9 Additional Preparation............................................................................................................... 24
3.2 Splicing ..................................................................................................................................... 24
3.2.1 Fusion Splicing .......................................................................................................................... 24
3.2.2 Mechanical Splicing .................................................................................................................. 25
3.2.3 Chemical Splicing ..................................................................................................................... 25
3.2.4 Environmental Seals ................................................................................................................. 25
3.2.5 Location .................................................................................................................................... 25
3.2.6 Protection .................................................................................................................................. 25
3.2.7 Testing ...................................................................................................................................... 25
3.3 Optical Fiber Cable Assemblies ................................................................................................ 25
3.4 Optical Fiber Assemblies ......................................................................................................... 26
3.5 Cleanliness ............................................................................................................................... 26
3.6 Inspection .................................................................................................................................. 26
3.7 Post-Assembly Test .................................................................................................................. 26
3.8 Post-Test Inspection ................................................................................................................. 26
3.9 Documentation .......................................................................................................................... 27

4 INSTALLATION ........................................................................................................................ 29
4.1 General Installation Requirements ........................................................................................... 29
4.1.1 Bundling (Fiber in the Wiring Harness) ..................................................................................... 29
4.1.2 Conduits .................................................................................................................................... 29
4.1.3 Bend Radii ................................................................................................................................ 29
4.1.4 Axial Alignment ......................................................................................................................... 29
4.1.5 Tensile Load ............................................................................................................................. 29
4.1.6 Mating ....................................................................................................................................... 29
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4.1.7 Torqueing .................................................................................................................................. 30
4.1.8 CTE Issues ............................................................................................................................... 30
4.2 Routing ...................................................................................................................................... 30
4.3 Protection and Support ............................................................................................................. 30

5 CLEANING ............................................................................................................................... 31
5.1 General Requirements .............................................................................................................. 31
5.1.1 Solvents .................................................................................................................................... 31
5.1.2 Canned Air ................................................................................................................................ 31
5.1.3 Compressed Air / Dry Nitrogen / Other Gas Media .................................................................. 32
5.1.4 Wipes / Swabs .......................................................................................................................... 32
5.2 Drying ........................................................................................................................................ 32

6 DOCUMENTATION .................................................................................................................. 33
6.1 General ..................................................................................................................................... 33
6.2 Data........................................................................................................................................... 33
6.3 Connector Orientation (Clocking) ............................................................................................. 34
6.4 Connector Pin-Out .................................................................................................................... 34
6.5 Dimensioning And Tolerance .................................................................................................... 34
6.6 Documentation For Maintenance / Emergency Restoration ..................................................... 34

7 TAILORING .............................................................................................................................. 37

8 QUALITY ASSURANCE REQUIREMENTS – GENERAL & VISUAL .................................... 39
8.1 Product Class Conditions ......................................................................................................... 39
8.2 Inspection .................................................................................................................................. 39
8.3 Responsibility For Inspections And Tests ................................................................................. 40
8.4 Classification Of Inspections And Tests ................................................................................... 40
8.4.1 Parts, Materials, And Process Controls .................................................................................... 40
8.4.2 Configuration Audit ................................................................................................................... 41
8.4.3 Acceptance And Qualification Testing ...................................................................................... 41
8.4.3.1 Acceptance Test ....................................................................................................................... 41
8.4.3.2 Qualification .............................................................................................................................. 41
8.4.4 Workmanship ............................................................................................................................ 42
8.4.4.1 Bare / Cleaved Fiber ................................................................................................................. 42
8.4.4.2 Fiber Optic Termination ............................................................................................................ 42
8.4.4.3 Connector ................................................................................................................................. 43
8.4.4.4 Fiber Assembly / Cable Assembly ............................................................................................ 43
8.4.4.5 Identification .............................................................................................................................. 43
8.4.4.6 Damage .................................................................................................................................... 43
8.4.4.7 Post-Test Inspection .............................................................................................................. 44
8.4.5 Visual Acceptance Criteria ........................................................................................................ 49
8.4.5.1 General ..................................................................................................................................... 49
8.4.5.2 Bare / Cleaved Fiber ................................................................................................................. 55
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8.4.5.3 Connectorized Fiber (PC / APC Polish and Receptacles With Internal Fiber Stubs) ............... 65
8.4.5.5 Splices ...................................................................................................................................... 79
8.4.5.6 Strain Relief / Strength Member ............................................................................................... 87
8.4.5.7 Insulation Jacket(s) ................................................................................................................... 89

9 QUALITY ASSURANCE REQUIREMENTS – TEST ............................................................... 91
9.1 Link Loss Budget ...................................................................................................................... 91
9.2 Test Conditions ......................................................................................................................... 91
9.2.1 Standard Test Conditions ......................................................................................................... 91
9.2.2 Extended Test Conditions ......................................................................................................... 92
9.3 Safety Precautions .................................................................................................................... 92
9.3.1 Laser Service Group Definitions ............................................................................................... 92
9.3.2 Laser Safety Precautions .......................................................................................................... 92
9.3.3 Personnel Safety Precautions .................................................................................................. 93
9.4 Acceptance and Qualification Testing ...................................................................................... 93
9.4.1 Receiving & Inspection ............................................................................................................. 93
9.4.2 Acceptance Test ....................................................................................................................... 93
9.4.2.1 Pre-Installation Tests ................................................................................................................ 93
9.4.2.2 Installation Tests ....................................................................................................................... 94
9.4.2.3 Post Installation Tests ............................................................................................................... 94
9.4.3 Testing After Rework or Repair ................................................................................................ 94
9.4.4 Test Discrepancy / Failure ........................................................................................................ 94
9.4.5 Qualification .............................................................................................................................. 94
9.5 Inspection .................................................................................................................................. 94
9.5.1 Visual (General) ........................................................................................................................ 94
9.5.2 Cable Inspection ....................................................................................................................... 95
9.5.3 Connector, Splice And Associated Hardware Inspection ......................................................... 95

10 DEFINITIONS AND ACRONYMS ............................................................................................ 97

11 TABLES .................................................................................................................................. 113
TABLE 1 BEND RADIUS ....................................................................................................................... 115
TABLE 2 OPTICAL FIBER/CABLE LENGTH MEASUREMENT / TOLERANCE .................................. 115
TABLE 3 MAGNIFICATION AIDS .......................................................................................................... 117
TABLE 4 STANDARD TEST CONDITIONS .......................................................................................... 119
TABLE 5 EXTENDED TEST CONDITIONS .......................................................................................... 119
TABLE 6 OPTICAL POWER (ABSOLUTE POWER & POWER LOSS) ................................................ 121
TABLE 7 TYPICAL TRANSMITTER SPECIFICATIONS ....................................................................... 121
TABLE 8 COMPARISON OF LED AND LD TRANSMITTER PARAMETERS ...................................... 123
TABLE 9 COMPARISON OF OPTICAL CABLE TYPES ....................................................................... 125
TABLE 10 TYPICAL OPTICAL FIBER SPECIFICATIONS ...................................................................... 127

APPENDICES - HOW TO USE THE APPENDICES ............................................................................... 129
APPENDIX A – MILITARY / SPACE APPLICATIONS REQUIREMENTS ............................................... 131
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APPENDIX B - TEST METHODS FOR THE INITIAL TESTING AND QUALIFICATION OF OPTICAL
FIBER, OPTICAL CABLE, AND ASSOCIATED DEVICES .................................................... 133
APPENDIX C - VERIFICATION & VALIDATION MATRIX ....................................................................... 141

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1 GENERAL
1.1 Scope
This document provides acceptance requirements and technical insight that have been removed from the
acceptance standards for cable and wire harness assemblies incorporating optical fiber, optical cable and
hybrid wiring technology. Reference materials listed in this text are among those considered as required
reading. The User is encouraged to obtain all relevant referenced materials as this document cannot (nor
can any single document) cover every material, process, environment, performance, or safety aspect that
affect a given design. <47E>
1.2 Purpose
This standard is intended to provide information on the
design and acceptance requirements for optical fiber, optical
cable, hybrid wiring harness assemblies, and Fiber Optic
Communications Systems (FOCS) to the extent that they can
be applied to the broad spectrum of optical cable and wiring
harness design.

Neither this document, nor its appendices, provide detailed
procedures for the test, acceptance, commissioning, and /or
maintenance of Fiber Optic Communications Systems
(FOCS).

This document is intended for use by the design engineer,
manufacturing engineer, quality engineer, or other individual
responsible for the tailoring of specific requirements of this
document to the applicable performance class.

FIGURE 1-1
a. This document defines acceptability criteria and limits for Optical Fiber Assemblies, Cables,
“New / Beginning of Life” hardware and it is not the intent And Wiring Harnesses
of this document to establish or define “In Service” Connector, Splice, and Transmitter
Image Credit: NASA
acceptance criteria to address performance or reliability

issues caused by aging or use. However, the
acceptability criteria and limits that are currently detailed
in this document may be considered to be wide enough to be applicable to the more common
hardware degradation conditions caused by aging / use. Use of these criteria for acceptance of “In
Service” hardware conditions shall [D1D2D3] be AABUS. <A363T>

b. It is not the intent of this document to exclude any alternate or contractor-proprietary documents or
processes that meet or exceed the baseline of requirements established by this document. Use of
alternate or contractor-proprietary documents or processes shall [D1D2D3] require review and prior
approval of the User.

c. For purposes of this document:
(1) The Designer is the design agent for the User.
(2) The User is the individual, organization, company, contractually designated authority, or agency
responsible for the procurement or design of electrical / electronic / electromechanical (EEE)
hardware, and having the authority to define the class of equipment and any variation or
restrictions to the requirements of this document (i.e., the originator / custodian of the contract
detailing these requirements). The User is considered the Design Authority.
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(3) The Supplier is considered the individual, organization or company which provides the
Manufacturer (assembler) components (electrical, electronic, electromechanical, mechanical,
printed boards, etc.) and/or materials (solder, flux, cleaning agents, etc.).
(4) The Manufacturer is considered the entity that provides a service or product to the User. <186E>
1.3 Classification
a. This document recognizes that optical wiring harnesses and cable assemblies are subject to
classifications by intended end-item use. Three general end-product classes have been established
to reflect differences in producibility, complexity, functional performance requirements, and
verification (inspection/test) frequency. It should be recognized that there may be requirement
overlaps between classes.

b. The User is responsible for defining the product class. The contract shall [D1D2D3] specify the
performance class required, whether compliance to any of the Appendices is required, and indicate
any exceptions to specific parameters where appropriate.”

CLASS 1 - General Electronic Products
Includes products suitable for applications where the major requirement is function of the completed
assembly. <187E>

CLASS 2 - Dedicated Service Electronic Products
Includes products where continued performance and extended life is required, and for which
uninterrupted service is desired but not critical. Typically, the end-use environment would not cause
failures.

CLASS 3 - High Performance / Harsh Environment Electronic Products
Includes products where continued high performance or performance-on-demand is critical, equipment
downtime cannot be tolerated, end-use environment may be uncommonly harsh, and the equipment must
function when required, such as life support or other critical systems.

MILITARY / SPACE
Includes products from Class 3 – High Performance / Harsh Environment Electronic Products, with
additional considerations for unique materials requirements and more extreme operational environments,
such as vibration and thermal cycling. Military / Space classification deviations to IPC-A-640
requirements are defined and listed in Appendix A, “Military / Space Applications Requirements”.
<188E><A329E><A338E>
1.4 Definition of Requirements
The imperative form of action verbs are used throughout this document to identify acceptance
requirements that may require compliance, depending upon the Performance Classification of the
hardware. To assist the User, these action verbs are in bold text.
a. SHALL / SHALL NOT. The words shall or shall not are used whenever a requirement is intended to
express a provision that is mandatory. Deviation from a shall or shall not requirement for a
particular Performance Class may be considered if sufficient technical rationale / objective evidence
(OE) is supplied to the User to justify the exception.
b. SHOULD. The word should is used whenever a requirement is intended to express a provision that
is non-mandatory, and which reflects general industry practice and / or procedure.
1.5 Requirement Format (N/A/D)
To assist the User, each requirement is identified by its Performance Classification (x1x2x3) and
applicability, where “x” represents: <50E><183E>
N = No requirement has been established for this Class
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