New Harness Assembly Standard Now Available
Posted by Paul Nelson on Wed, Jul 03, 2013
The IPC/WHMA-A620 standard for the acceptance of wire harness and cable assemblies, Requirements and Acceptance for Cable and Wire Harness Assembies, has been embraced with worldwide approval since it first became available in 2002. Revision A of the standard was published in 2006, and incorporated a wide range of refinements related to harness testing.
Revision B of the A-620 has recently been released, and training materials will be forthcoming on or about March 2013. The 400-page A-620B reflects the review and resolution of more than 400 user comments on Revision A, and has been under development for over three years. Like all prior versions, it was developed jointly by the Wire Harness Manufacturers Association (WHMA) and IPC (Association Connecting Electronics Industries).
One of the reasons for the standard's wide acceptance is its wide applicability across products and industries. Every effort has been made to ensure that the A-620 is applicable and useful for assemblies that will be part of electronics, medical devices, vehicles, custom machinery or nearly any other manufactrured product.
Both harness assemblers and OEMs use the A-620 standard for a variety of reasons related to enhanced product quality, including:
- As a definitive workmanship standard for technicians
- To train employees to spot defects, so they can act as "inline quality inspectors" whatever their job and level of training or certification
- For incorporation into quality management systems (QMS) in support of ISO and regulatory requirements
- To support data collection towards achieving operational excellence
- As a marketing tool for contract manufacturers, to build employee involvement and pride in workmanship
According to Lyle Fanning as quoted in the magazine Assembly, WHMA chairperson, "No chapter has been untouched, from minor wording changes to major overhaul." The new A-620B also contains more than 100 new or uploaded illustrations and photos.
Among the key changes in the A-620B is an addendum specifically covering cables and wire harness used in rockets, satellites and other spacecraft. This new material seeks to unify military and NASA standards, with some NASA strandards being rescinded in favor of the new A-620B criteria.
Because of the added rigor and specificity required for space-related cables and wire harnesses, these criteria were intentionally not integrated into the body of the standard. To assemble and test wire harnesses for space applications, technicians must be IPC-certified to the A-620AS addendum, and must complete five days of hands-on assembly practice.
Other significant changes and additions in the A-620B include:
- Chapter 4, "Soldering to Terminals," is now aligned with other IPC standards
- Chapter 6, "Insulation Displacement Connectors," includes information on pass-through connectors
- An expanded Chapter 8, "Soldering and Crimp Splices," to incorporate inline jiffy connection devices and better align wording for the various types of splices
- Chapter 13, "Connectorization," adds new acceptance criteria for pin damage, along with new photos
- A new section for clamping in Chapter 17, "Finished Assembly Installation."
Another reason the A-620B has enjoyed worldwide adoption is that it has been translated into seven languages: English, German, French, Spanish, Danish, Polish and Chinese. Pending the release of the A-620B, it will also be available in additional languages. Over 1,000 businesses worldwide employ at least one person who is IPC-certified to train others in the use of the standard, and more than 11,000 people are currently certified as either trainers or assemblers. The publication of Revision B does not entail recertification; current IPC certifications will remain valid for the normal two-year period.