# WHMA and wire harness manufacturing: the A-620 standard, harness BOMs and the ERP problems that follow > Source: https://netray.co/manufacturing/whma-wire-harness-manufacturers-association > Publisher: Netray (netray.co), AI and integration engineering for ERP and manufacturing systems. > Section: Manufacturing Hubs ## Short answer The Wire Harness Manufacturers Association (WHMA) is a trade association serving companies that build cable and wire harness assemblies, and it co-develops IPC/WHMA-A-620, the main acceptance standard for the field. Harness shops are high-mix, labor-intensive and driven by customer drawings and revisions. This page covers the standards, the ecosystem and the ERP and data issues typical of harness and cable assembly. ## Kind association ## Country Global ## Area Cable and wire harness manufacturing ## Intro The Wire Harness Manufacturers Association (WHMA) is a trade association serving companies that build cable and wire harness assemblies, and it co-develops IPC/WHMA-A-620, the main acceptance standard for the field. Harness shops are high-mix, labor-intensive and driven by customer drawings and revisions. This page covers the standards, the ecosystem and the ERP and data issues typical of harness and cable assembly. ## Industries ### Aerospace and defense harnesses **Detail:** Point-to-point harnesses and box builds use qualified connectors, contacts and wire, with documented crimp tooling and inspection, and traceability to lot. ### Automotive and off-highway **Detail:** Higher-volume harnesses for vehicles, trucks and equipment, often built to OEM specifications and USCAR or manufacturer test requirements, with strong variant and configuration complexity. ### Medical and industrial equipment **Detail:** Cable assemblies for devices, instrumentation and machinery, built to lower volumes with customer-specific testing and sometimes ISO 13485 controls. ### Telecom and data cable assemblies **Detail:** Coax, fiber and multi-conductor assemblies where termination quality and electrical testing drive acceptance. ## Ecosystem ### Wire Harness Manufacturers Association (WHMA) **Type:** association **Note:** An association for wire harness and cable assembly manufacturers that operates in close partnership with IPC. ### IPC/WHMA-A-620 **Type:** standard body **Note:** Requirements and Acceptance for Cable and Wire Harness Assemblies, jointly developed by IPC and WHMA. ### IPC/WHMA-A-620 training and certification **Type:** training **Note:** Certified application specialist and trainer programs are offered through IPC authorized training centers. ### IPC APEX EXPO **Type:** trade show **Note:** IPC's annual electronics manufacturing event, where wire harness topics are also covered. ### IPC **Type:** association **Note:** Publishes the related standards family, including IPC-A-610 and J-STD-001. ### USCAR-21 **Type:** standard body **Note:** A performance specification for wire-to-terminal crimps used in automotive supply chains. ### NASA-STD-8739.4 **Type:** standard body **Note:** NASA workmanship standard covering crimping, interconnecting cables, harnesses and wiring. ## Requirements - IPC/WHMA-A-620 class requirements (Class 1, 2 or 3 as specified), with the space addendum where flowed down - Crimp height, pull-force and tooling calibration records - AS50881 aircraft wiring practice and MIL-DTL-38999 connector requirements on aerospace programs - USCAR-21 and OEM specifications for automotive harnesses - AS9100, IATF 16949 or ISO 13485 as the end market requires - Continuity and hipot testing records per customer drawing - Lot traceability for wire, terminals and connectors ## Sections ### How harness shops differ from other electronics shops **Body:** A harness is mostly manual work around a formboard: cut, strip, crimp, assemble, tape or sleeve, then test. Costs sit in labor, wire and connector variety, and in drawing revisions. A single product family may have many variants that differ by a few circuits, which makes configuration control and bill of materials structure central. Quality is inspected against A-620 and the customer drawing, and most defects come from crimp quality, wrong cavity placement and revision errors rather than from machine faults. ### Quoting and estimating harnesses **Body:** Quotes need circuit counts, wire lengths and gauges, terminal and seal types, connector and backshell parts, labeling, test requirements and tooling. Labor standards per operation vary a lot between simple and complex builds. Hard-to-source connectors and long lead times often decide feasibility more than price does. **Bullets:** - Estimate from the wire list and drawing, not from connector count alone - Include tooling, applicators and test fixtures as separate lines - Record revision and class on the quote and traveler ### ERP, harness design and data realities **Body:** Harness shops commonly use ERP systems such as Epicor Kinetic, Infor SyteLine/CloudSuite Industrial, Global Shop Solutions, JobBOSS, E2, NetSuite or Plex, and sometimes dedicated harness design or wire list tools. Wire length, cut lists, terminal part numbers and test programs often start in an engineering tool or spreadsheet and are re-keyed into the ERP. That re-keying is where mismatches arise: a BOM that omits a seal, a revision that differs between the traveler and the drawing, or an alternate terminal used without approval. Fewer manual hand-offs is the most reliable fix. ### Where private AI helps harness shops, and where it does not **Body:** Useful, bounded tasks include cross-checking a quote or BOM against a customer drawing, finding every job built with a given terminal lot after a crimp issue, searching procedures and past nonconformance reports, and answering questions over ERP data without building a report. Running models on-premises suits customers who restrict drawing and export-controlled data. AI is not a substitute for crimp pull testing, continuity and hipot testing, or trained inspectors applying A-620. Write-back to the ERP should stay behind human approval. ## Faq ### What does WHMA stand for? **Answer:** WHMA stands for the Wire Harness Manufacturers Association. It serves companies that design and build wire harnesses and cable assemblies, and works with IPC on standards and training such as IPC/WHMA-A-620. ### What is IPC/WHMA-A-620? **Answer:** It is the Requirements and Acceptance for Cable and Wire Harness Assemblies standard. It describes acceptable workmanship for crimping, soldering, wire preparation, routing and related operations, by product class, and is commonly cited on harness drawings and contracts. ### Do I need A-620 certification to build harnesses? **Answer:** It is not a legal requirement, but many customers, especially in aerospace and defense, require trained and certified personnel and flow the standard down in their contracts. Check the purchase order and quality clauses for the specific requirement. ### Why are harness BOMs hard to manage in ERP? **Answer:** Harnesses have many variants, large numbers of low-cost parts and frequent revision changes. If wire lists and cut data live outside the ERP, mismatches creep in. A clear BOM structure and one source of truth for revisions reduces errors. ## Search terms whma, wire harness manufacturers association, ipc whma a 620, ipc standards for wiring harness, wire harness manufacturing erp, wire harness quoting software, cable assembly ipc standards --- Talk to an engineer: https://netray.co/contact?intent=erp_ai | Machine catalog: https://netray.co/agent/catalog.json