What IPC/WHMA-A-620E Actually Is
IPC/WHMA-A-620E — published October 2022 — is the international standard that prescribes practices and requirements for the manufacture of cable, wire and harness assemblies. It is jointly developed by IPC (Association Connecting Electronics Industries) and WHMA (Wiring Harness Manufacturers Association), with contributions from participants in 23 countries.
It supersedes IPC/WHMA-A-620D (January 2020). The revision letter E is important — when you reference this standard on an engineering drawing or supplier contract, you must specify the revision. Using an outdated revision creates ambiguity during audits and can invalidate inspection results.
Scope: What the Standard Covers and What It Does Not
Section 1.1 defines the scope precisely. Many engineers assume IPC/WHMA-A-620 covers everything related to harness manufacturing. It does not. Understanding the boundary is critical when specifying the standard in a contract or purchase order.
Purpose: The Three Core Objectives
Section 1.2 states the purpose in precise technical language. Breaking it down reveals three distinct objectives that define how the standard should be used in practice.
The standard describes materials, methods, tests and acceptability criteria for producing crimped, mechanically secured, and soldered interconnections and related assembly activities. It tells you what a good harness looks like — not just what a bad one looks like.
The intent is to rely on process control methodology to ensure consistent quality levels during manufacture. The standard is not an inspection checklist — it is a process quality framework. Any method that produces a conforming assembly is acceptable.
Any method that produces an assembly conforming to the acceptability requirements described in this standard may be used. The standard defines the outcome, not the process. This gives manufacturers flexibility to optimize their assembly methods.
The standard is outcome-based, not method-based. It does not dictate how you crimp, how you route, or how you sleeve. It defines what the finished result must look like and how it must perform. This distinction matters when qualifying new tooling or processes — if the result meets the acceptance criteria, the method is valid.
How the Standard Uses Language
Understanding IPC/WHMA-A-620E requires understanding its precise use of three specific words. Misreading these is a common source of audit failures.
Shall — mandatory requirement
The word "shall" or "shall not" indicates a requirement for materials, process, or acceptance of cable, wire and harness assemblies. When you see "shall", it is not optional — it is a requirement for at least one product class, communicated via bracket notation [D1D2D3].
Should — recommendation only
The word "should" reflects recommendations and is used to reflect general industry practices and procedures for guidance only. A "should" requirement does not trigger a nonconformance. It is best practice guidance, not a pass/fail criterion.
The illustration warning
Many figures in IPC/WHMA-A-620E are grossly exaggerated to clearly depict the condition being described. The standard is explicit: in the case of a discrepancy, the written description or written criteria always takes precedence over the illustrations. Never base an accept/reject decision solely on how a figure looks — always refer to the written criteria.
English Version Precedence
IPC/WHMA-A-620E includes an explicit statement that is particularly relevant for bilingual operations in Quebec: if a conflict occurs between the English and translated versions of this document, the English version will take precedence.
This means that for any dispute, contract, or audit involving this standard, the English text is the authoritative reference. When LoomWire produces engineering packages referencing IPC/WHMA-A-620E for Quebec clients, we always include the English standard reference as the controlling document, even when delivering bilingual documentation.
Revision D vs Revision E: Key Differences
IPC/WHMA-A-620E supersedes revision D (January 2020). The revision cycle reflects input from the standard's technical committee and 23 contributing countries. Here are the practical differences that affect harness engineers in heavy equipment applications.
| Area | Revision D (2020) | Revision E (2022) | Status |
|---|---|---|---|
| Publication date | January 2020 | October 2022 | Updated |
| Participating countries | Not specified in D | 23 countries | Expanded |
| Scope statement | Cable and wire harness assemblies | Same — no change | Same |
| Three product classes | Class 1, 2, 3 defined | Same definitions — no change | Same |
| Crimp terminations §5 | Open and closed barrel criteria | Refined acceptance criteria for open barrel insulation support | Refined |
| Coaxial cable §13 | Semirigid coax criteria | Additional clarification on semirigid bending and surface conditions | Clarified |
| Shield termination §15 | Shield braid termination methods | Updated woven and combed braid criteria | Updated |
| Testing §19 | Pull force tables | Added UL, SAE, GM, Volvo pull force values (Table 19-13) | New table |
| X-ray guidelines | Appendix D | Same appendix — no change | Same |
| IPC certification | CIS and CIT programs | Same certification structure | Same |
Using IPC/WHMA-A-620E as a Purchasing Document
The standard explicitly states it can be used as a stand-alone document for purchasing products. In practice this means you can write a purchase order that references IPC/WHMA-A-620E Class 2 as the acceptance standard, and any qualified manufacturer will understand exactly what is required.
However three important limitations apply when using it this way:
- Inspection frequency is not specified. You must define whether you require in-process inspection, end-product inspection, or both — and at what sampling rate.
- Process indicators are not limited. The standard places no limit on the number of process indicators. If you want a limit, specify it separately.
- Repair/rework events are not limited. The standard places no limit on the number of allowable repair or rework operations. Define this in your quality requirements if it matters for your application.
Summary: What Every Harness Engineer Needs to Remember
- Always specify the revision — "IPC/WHMA-A-620E" not just "IPC/WHMA-A-620"
- The standard covers manufacture, not design — it tells you what acceptable looks like, not what to design
- Method-neutral — any process producing a conforming result is acceptable
- Inspection frequency is your responsibility — the standard does not specify it
- English text is authoritative — critical for bilingual Quebec operations
- "Should" is guidance, "shall" is mandatory — know the difference before auditing
- Written criteria override figures — train inspectors to read, not just look
- Revision E is current — for new work, always reference October 2022
Ce qu'est réellement l'IPC/WHMA-A-620E
L'IPC/WHMA-A-620E — publié en octobre 2022 — est la norme internationale qui prescrit les pratiques et exigences pour la fabrication des assemblages de câbles et faisceaux électriques. Elle est développée conjointement par l'IPC et la WHMA, avec la participation de 23 pays.
Elle remplace l'IPC/WHMA-A-620D (janvier 2020). La lettre de révision E est importante — lorsque vous référencez cette norme sur un dessin d'ingénierie ou un contrat fournisseur, vous devez spécifier la révision. L'utilisation d'une révision obsolète crée une ambiguïté lors des audits.
Domaine d'application : Ce que la norme couvre et ce qu'elle ne couvre pas
Objectif : Les trois objectifs fondamentaux
La norme décrit les matériaux, méthodes, essais et critères d'acceptabilité pour produire des interconnexions serties, mécaniquement fixées et soudées.
L'intention est de s'appuyer sur la méthodologie de contrôle de processus pour assurer des niveaux de qualité constants. La norme est un cadre de qualité de processus, pas une liste de contrôle d'inspection.
Toute méthode produisant un assemblage conforme aux exigences d'acceptabilité peut être utilisée. La norme définit le résultat, pas le processus.
Utilisation du langage dans la norme
Shall — exigence obligatoire
Le mot "shall" ou "shall not" indique une exigence pour les matériaux, le processus ou l'acceptation des assemblages. Lorsque vous voyez "shall", ce n'est pas optionnel.
Should — recommandation seulement
Le mot "should" reflète des recommandations et des pratiques industrielles générales à titre d'orientation seulement. Une exigence "should" ne déclenche pas une non-conformité.
La mise en garde concernant les illustrations
De nombreuses figures de l'IPC/WHMA-A-620E sont grossièrement exagérées pour illustrer clairement la condition décrite. La norme est explicite : en cas de divergence, la description écrite prend toujours le dessus sur les illustrations.
Préséance de la version anglaise
L'IPC/WHMA-A-620E inclut une déclaration explicite particulièrement pertinente pour les opérations bilingues au Québec : si un conflit survient entre les versions anglaise et traduite de ce document, la version anglaise prévaudra.
Cela signifie que pour tout litige, contrat ou audit impliquant cette norme, le texte anglais est la référence faisant autorité. LoomWire inclut toujours la référence anglaise de la norme comme document de contrôle, même lors de la livraison de documentation bilingue.
Révision D vs Révision E : Différences clés
| Domaine | Révision D (2020) | Révision E (2022) | Statut |
|---|---|---|---|
| Date de publication | Janvier 2020 | Octobre 2022 | Mise à jour |
| Pays participants | Non spécifié dans D | 23 pays | Élargi |
| Classes de produits | Classe 1, 2, 3 | Mêmes définitions | Inchangé |
| Sertissage §5 | Critères à baril ouvert et fermé | Critères raffinés pour le support d'isolation à baril ouvert | Raffiné |
| Câble coaxial §13 | Critères coax semi-rigide | Clarifications sur le cintrage et les conditions de surface | Clarifié |
| Essais §19 | Tableaux de force d'arrachement | Ajout des valeurs UL, SAE, GM, Volvo (Tableau 19-13) | Nouveau tableau |
Résumé : Ce que chaque ingénieur doit retenir
- Toujours spécifier la révision — "IPC/WHMA-A-620E" et non "IPC/WHMA-A-620"
- La norme couvre la fabrication, pas la conception
- Neutre sur les méthodes — tout processus produisant un résultat conforme est acceptable
- La fréquence d'inspection est votre responsabilité — la norme ne la spécifie pas
- Le texte anglais fait autorité — critique pour les opérations bilingues au Québec
- "Should" est une recommandation, "shall" est obligatoire
- Les critères écrits priment sur les figures
- La révision E est la version actuelle — octobre 2022
Need a harness engineered to IPC/WHMA-A-620E? Besoin d'un faisceau conçu selon l'IPC/WHMA-A-620E ?
LoomWire references IPC/WHMA-A-620E Revision E on every engineering package. We specify the class, the revision, and the inspection method — so your supplier has no room for interpretation. LoomWire référence l'IPC/WHMA-A-620E révision E sur chaque package d'ingénierie. Nous spécifions la classe, la révision et la méthode d'inspection — sans aucune ambiguïté pour votre fournisseur.