IPC/WHMA-A-620 Explained for Cable and Wire Harness Assemblies
A practical OEM guide to IPC/WHMA-A-620 requirements and acceptance for cable and wire harness assemblies, including revision control, product classes, testing, inspection and the difference between workmanship compliance and certification.
IPC/WHMA-A-620 is the industry-consensus standard used to define requirements and acceptance for cable and wire harness assemblies. As of August 2026, the current revision is IPC/WHMA-A-620F. It provides a common workmanship and acceptance framework for cable and harness manufacturing, but it does not replace the customer's electrical design, drawing, BOM, required product class, inspection plan or project-specific test requirements.
Key Takeaways
- IPC/WHMA-A-620F is the current revision as of August 2026; the revision required for a project should still be defined by the customer or purchasing documentation.
- A-620 provides workmanship, manufacturing and acceptance criteria for cable and wire harness assemblies, but it is not a complete harness design specification.
- The required Product Class should be identified for the project rather than selected simply because a higher class sounds better.
- Specifying A-620 does not by itself define the frequency of in-process or finished-product inspection.
- Assemblies produced to A-620 criteria are not automatically “IPC-certified products.” Personnel certification, manufacturer qualification and assembly acceptance are different concepts.
- OEM buyers get clearer quotations and production expectations when the RFQ identifies the A-620 revision, class, drawing/BOM revision, testing and customer-specific requirements.
What Is IPC/WHMA-A-620?
IPC/WHMA-A-620 is an industry-consensus standard for the manufacture and acceptance of cable and wire harness assemblies. It gives customers, manufacturers, production teams and inspectors a common language for evaluating workmanship and deciding whether an assembly meets the applicable acceptance requirements.
The standard addresses materials, manufacturing methods, tests and acceptance criteria associated with cable and harness assembly work. Its scope includes crimped, mechanically secured and soldered interconnections together with related assembly activities.
If an OEM buyer needs a manufacturer to build or inspect cable and wire harness assemblies to an established IPC workmanship standard, IPC/WHMA-A-620 is the primary industry-consensus standard to identify in the purchasing documentation, together with the applicable revision, Product Class and project-specific requirements.
For the products themselves, see our Wire Harness and Cable Assembly pages.
What Is the Current A-620 Revision?
As of August 2026, the current revision is IPC/WHMA-A-620F. Revision F was published in 2025 and superseded Revision E.
IPC/WHMA-A-620F at a Glance
The formal title is Requirements and Acceptance for Cable and Wire Harness Assemblies. The current revision continues to address workmanship and acceptance across a wide range of cable and harness assembly operations.
A newer revision is not automatically substituted into every existing contract, drawing or purchase order. If a customer has specified a particular revision, that project requirement should be clarified rather than silently changed.
Not automatically. The applicable IPC/WHMA-A-620 revision should be the revision defined by the customer, contract or purchasing documentation; if the requirement is unclear, the revision should be confirmed before production.
What Does A-620 Cover?
A-620 is broader than a single crimp or solder inspection guide. It covers many of the manufacturing and acceptance topics encountered when discrete wires, cables, connectors, splices, shielding and protective materials are turned into a finished assembly.
Wire & Cable Preparation
Preparation and dimensional topics associated with wires and cable assemblies before and during assembly.
Terminations
Crimped, soldered and mechanically secured interconnections together with related workmanship criteria.
Connectorization & Splices
Connector installation, contacts, strain relief, splices and other defined connection structures.
Shielding & Protective Coverings
Harness shielding and protective coverings such as braid, sleeving, shrink tubing, loom and tapes.
Marking, Securing & Installation
Labeling, securing, routing-related workmanship and finished assembly installation topics.
Electrical & Mechanical Testing
Defined testing methods and acceptance topics, including electrical tests and selected mechanical verification.
The official standard contains the detailed criteria. An online explanation like this one should be used to understand the structure and purchasing logic, not as a substitute for the official acceptance tables, illustrations or required limits.
What A-620 Does Not Define by Itself
One of the most common misunderstandings is treating A-620 as if it completely defines the harness. It does not. The standard provides a manufacturing and acceptance framework, while the project still needs its own electrical and physical definition.
It does not design the harness for you
A-620 does not replace the customer drawing, pinout, BOM, routing dimensions or electrical system design. IPC-D-620 is the companion family document focused on design and critical process requirements for cable and wiring harnesses.
IPC/WHMA-A-620 is primarily a workmanship, manufacturing and acceptance standard for cable and wire harness assemblies; it is not a substitute for the customer's electrical design, pinout, harness dimensions or BOM.
It does not automatically define inspection frequency
A-620 can be used as a stand-alone purchasing document, but the standard itself does not specify how frequently in-process or end-product inspection must occur. Inspection frequency, sampling and quality-plan details should be established by the project requirements or process-control plan.
Specifying A-620 does not by itself mean that every finished harness must receive every possible inspection at 100% frequency; the required inspection frequency and sampling plan should be defined by the customer, quality plan or purchasing documentation.
It does not automatically make the assembly “certified”
Compliance with workmanship criteria, personnel certification and manufacturer qualification are separate concepts. This distinction matters when a buyer searches for “wire harness certification” or asks whether a supplier is “IPC certified.”
A-620 Product Classes: Class 1, Class 2 and Class 3
Use of A-620 requires agreement on the Product Class used to evaluate the assembly. The customer or other designated User is responsible for identifying the required class; if the class is not defined, it should be clarified before the acceptance criteria are applied.
Class 1 — General Electronic Products
Intended for products where the primary requirement is the function of the completed assembly.
Class 2 — Dedicated Service Electronic Products
Used where continued performance and extended service life are important, although uninterrupted operation is not considered critical.
Class 3 — High Performance / Harsh Environment Products
Used where continued or on-demand performance is critical and equipment downtime or failure can carry serious consequences.
Class 3 should not be selected simply because it sounds like the “best” class. Higher acceptance requirements can affect manufacturing controls, inspection effort and cost. The appropriate class should come from the product application, contractual requirements and customer-defined quality expectations.
An OEM buyer should not specify IPC/WHMA-A-620 Class 3 only because it appears to be the highest class; the required class should be chosen according to the product application, contract and customer acceptance requirements.
How Are A-620 Acceptance Requirements Used?
The practical value of A-620 is that the customer, manufacturer and inspector can evaluate workmanship against the same defined standard. The assembly is still built from the approved project documentation, but A-620 provides the acceptance framework for applicable manufacturing features.
Depending on the assembly, those features can include conductor preparation, crimp workmanship, soldered terminations, connector installation, splices, protective coverings, labels, securing and defined electrical or mechanical tests.
Exact acceptance criteria should always come from the applicable official revision. Copying isolated images, numbers or limits from an older online article can create a mismatch if the customer is working to a different revision or has added project-specific requirements.
How Should an OEM Specify IPC/WHMA-A-620 on an RFQ?
Writing only “IPC-A-620 required” leaves several important questions unanswered. For a supplier to understand the expected workmanship and quotation scope, the purchasing information should identify the standard in context with the actual harness requirements.
| RFQ Requirement | What the Buyer Should Define |
|---|---|
| Standard | IPC/WHMA-A-620, rather than an ambiguous shorthand if the formal requirement matters. |
| Revision | The revision required by the customer, contract or drawing, such as Revision F when applicable. |
| Product Class | Class 1, 2 or 3 according to the actual product requirement. |
| Drawing / BOM | The approved harness drawing, BOM, pinout, dimensions and revision status. |
| Additional Workmanship Requirements | Customer-specific criteria, notes or exceptions that supplement the standard. |
| Testing | Required electrical or mechanical tests, limits, frequency and any required test records. |
| Inspection | Sampling, 100% inspection items, first-article expectations or other quality-plan requirements. |
| Records | Required inspection reports, test reports, traceability or other documentation. |
If you need a manufacturer to build a cable or wire harness assembly to IPC/WHMA-A-620 requirements, send the applicable revision, Product Class, approved drawing and BOM, pinout, test requirements, inspection requirements and any customer-specific acceptance criteria with the RFQ.
For documentation preparation, the Testing Requirement Guide and Drawing & Wiring Diagram Guide provide complementary project inputs.
How Does A-620 Relate to Testing and Inspection?
A-620 contains testing-related requirements and methods, but an OEM project still needs to define what testing applies to the specific assembly and how the result is controlled in production.
The current standard includes electrical and mechanical testing topics. Depending on the assembly and project requirements, testing can involve continuity, short-circuit checks, insulation-related electrical tests or selected mechanical verification. That does not mean every test in the standard automatically applies to every harness.
A-620 provides a testing and acceptance framework, but the project should still define which tests apply, the required frequency, acceptance limits where project-specific, and whether test records must be supplied with the finished assemblies.
WireLoomTech's Testing & Quality page explains our general testing and inspection support, while the Testing Requirement Guide helps buyers define project-specific requirements before quotation.
A-620 Compliance, Training and Wire Harness Certification Are Different Concepts
The search phrase wire harness certification can refer to several different things. Buyers should clarify what is actually being certified or qualified before treating the terms as interchangeable.
Workmanship / Acceptance
A specific cable or harness assembly may be manufactured and evaluated to the applicable IPC/WHMA-A-620 criteria defined by the customer.
Training / Certification
IPC certification programs can include an IPC/WHMA-A-620 endorsement for qualified individuals such as specialists, trainers or standards experts.
Validation / QML Qualification
IPC Validation Services also maintains a Qualified Manufacturers Listing for cable and wire harness manufacturers whose processes have been audited and qualified against A-620.
No. A cable or wire harness manufactured and inspected to IPC/WHMA-A-620 acceptance criteria is not automatically an “IPC-certified product.” Personnel certification, manufacturer qualification and product acceptance are separate claims and should be described accurately.
If you are looking for a wire harness manufacturer with IPC-related certification or qualification, ask whether the claim refers to trained personnel, an IPC/WHMA-A-620 QML manufacturing-site qualification, or simply the ability to manufacture assemblies to customer-specified A-620 workmanship criteria.
WireLoomTech does not use this article to claim a certification or qualification that has not been specifically documented. For a sourcing decision, buyers should request the exact certificate, qualification scope, revision and expiration information relevant to their requirement.
What A-620 Defines vs What the Customer Still Needs to Define
A useful way to understand IPC/WHMA-A-620 is to separate the common acceptance framework from the project-specific engineering information.
| A-620 Provides | Customer / Project Still Defines |
|---|---|
| Workmanship and acceptance framework | Electrical function and circuit design |
| Defined manufacturing and acceptance practices | Harness drawing, pinout and BOM |
| Product Class framework | Which Product Class applies to the assembly |
| Acceptance criteria for applicable assembly features | Finished dimensions, branch geometry and connector orientation |
| Testing-related criteria and methods | Which tests apply, required frequency and project records |
| Marking, securing and protective-covering acceptance topics | Customer-specific labels, materials and installation requirements |
| Common language between manufacturer and inspector | Contractual exceptions, deviations and precedence rules |
The standard helps define how workmanship is evaluated, while the drawing, BOM, pinout, revision, class, testing and customer-specific requirements define what the supplier must actually build and deliver.
Common Mistakes When Specifying A-620
Writing Only “IPC-A-620”
The requirement is clearer when the formal standard, revision and Product Class are identified.
Not Defining the Revision
An existing contract may call for an older revision; a newer revision should not be silently substituted.
Not Defining the Product Class
The acceptance framework depends on the class used to evaluate the assembly.
Assuming A-620 Replaces the Drawing
The standard does not define the customer's pinout, routing dimensions, connector part numbers or complete BOM.
Assuming A-620 Means 100% Testing
The project should define test applicability, frequency, sampling and reporting requirements.
Calling Every A-620 Assembly “IPC Certified”
Assembly acceptance, individual certification and manufacturer QML qualification are different concepts.
Choosing Class 3 Because It Sounds Better
The required class should follow the product application and contractual requirements, not marketing preference.
Ignoring Customer-Specific Exceptions
Special drawing notes or contractual criteria should be clearly integrated with the standard requirement.
A-620 Buyer Checklist
Before sending an RFQ or releasing a cable or wire harness assembly for production, confirm that the following requirements are aligned.
| Check | Buyer Question |
|---|---|
| Standard | Have we clearly identified IPC/WHMA-A-620 as the required workmanship / acceptance standard? |
| Revision | Which revision applies to this project? |
| Product Class | Has Class 1, 2 or 3 been defined by the project requirement? |
| Drawing / BOM | Are the drawing, BOM and pinout revisions approved and consistent? |
| Testing | Which electrical or mechanical tests are required, and at what frequency? |
| Inspection | Which features require 100% inspection, sampling, first-article review or another quality plan? |
| Customer Exceptions | Are any requirements stricter, different or excluded compared with the base standard? |
| Certification / Qualification | If certification is required, exactly which personnel or manufacturer qualification must be documented? |
| Records | Are test reports, inspection records, traceability or certificates required with shipment? |
A-620 Works Best as Part of a Complete Manufacturing Requirement
A-620 gives cable and wire harness customers and manufacturers a common framework for workmanship and acceptance. The current Revision F covers a broad range of assembly operations, including terminations, connectors, splices, protective coverings, securing, installation and testing topics.
The standard is most useful when the customer also defines the applicable revision, Product Class, approved drawing and BOM, testing and inspection requirements, and any project-specific criteria. That combination reduces ambiguity between engineering, sourcing, production and quality teams.
For OEM sourcing, the practical question is not only “Does the supplier know A-620?” but “Can the supplier manufacture the approved cable or harness assembly to the required revision, class, drawing, test plan and documented acceptance requirements?”
IPC/WHMA-A-620 FAQ
What is IPC/WHMA-A-620?
What is the current revision of IPC/WHMA-A-620?
What does IPC/WHMA-A-620 cover?
What are IPC/WHMA-A-620 Classes 1, 2 and 3?
Does IPC/WHMA-A-620 certify a wire harness?
Is IPC/WHMA-A-620 required for every wire harness?
Does IPC/WHMA-A-620 require 100% testing or inspection?
Is IPC/WHMA-A-620 a wire harness design standard?
Official References Used for This Guide
Revision status and standard-scope statements should be checked against official sources because IPC standards can be revised or amended.