IPC/WHMA-A-620E Requirements and Acceptance for Cable and Harness Assemblies

Developed jointly by the Printed Circuits Institute (IPC) and the Wire Harness Manufacturers Association (WHMA), the standard "IPC/WHMA-A-620E Requirements and Acceptance for Cable and Wire Harness Assemblies" is the only industry consensus standard for requirements and acceptance of cable and wire harness assemblies. This standard describes the materials, methods, testing, and acceptance criteria for producing crimped, mechanically fastened, and soldered interconnects, and related assembly activities associated with cable and wire harness assemblies.

Both wiring harnesses and cable assemblies provide electrical connections while keeping cables and wires organized and together. These systems transmit signals or electrical power in most automobiles and aircraft. This standard specifies requirements for producing crimped, mechanically secured, and soldered interconnects for cable and harness assemblies.

The terms "wire harness" and "cable assembly" are often used interchangeably, but wires and cables are not the same. A wire is a single strand of electrically conductive material, such as tin or copper. A wire assembly organizes electrical wires and cables by grouping them together. It provides a sheathing, typically made of the same material used in a cable assembly, that surrounds the individual wires. Wire assemblies cannot protect the wires from extreme temperatures or friction between them, so they are primarily used for indoor use and are found in most automobiles and aircraft.

Many everyday household products, such as computers, televisions, monitors, microwaves, and refrigerators, use cable assemblies. These products are often enclosed in a protective sheath, eliminating the need for additional shielding. A cable is a bundle of wires twisted or braided together, enclosed in a single, protective outer sheath, forming a single, thick wire. Cable assemblies provide greater protection by keeping components tightly enclosed within a durable outer sheath. They keep all products safe in extreme environmental conditions and temperature fluctuations, making them ideal for outdoor use. Cable assemblies offer a high level of resistance to external factors (e.g., heat, dust, and moisture) and protect wires and cables from friction and corrosion. Many heavy industries, such as medical, military, aerospace, and construction, often utilize cable assemblies in their manufacturing processes because they are ideal for high-speed data transfer.

IPC/WHMA A-620E standard describes the materials, methods, tests, and acceptance criteria for producing crimped, mechanically fastened, and soldered interconnects. It also specifies related assembly activities associated with cable and harness assemblies. This standard details requirements for wire stripping, wire damage and end cuts, conductor deformation/birdcaging, wire twisting, insulation damage, solder termination, center conductor termination, solder joints, tinning, turrets and straight pins, semi-rigid coaxial, and much more. The purpose of this standard is to rely on process control methodology to ensure consistent quality levels during product manufacturing. This standard does not provide criteria for cross-sectional or X-ray evaluation.

Use of this standard requires agreement on the class to which the product belongs. The user (or manufacturer) has ultimate responsibility for determining the class in which the assembly is evaluated. The criteria defined in this standard reflect three product classes:

• Class 1 General electronic products: Includes products suitable for applications where the primary requirement is the function of the completed assembly.
• Class 2 Special-service electronic products: Include products where sustained performance and extended life are required and uninterrupted service is desired but not critical. Typically, the end-use environment will not cause failures.
• Class 3 High-performance/harsh environment electronic products: Includes products where continuous performance or on-demand performance is critical, equipment downtime cannot be tolerated, the end-use environment may be unusually harsh, and the equipment must operate when needed, for example, life support systems and other critical systems.

Wire harnesses and cable assemblies solve many of the challenges associated with complex electrical systems. Because they are specifically designed, they can significantly increase a system's efficiency. These assemblies are used to transmit electronic signals in many types of equipment across various industries, including:

• Aviation: Cables and wiring harnesses provide power transmission in aircraft engines, data transmission from satellites, and space force systems.
• Automotive: Extensive use of wiring harnesses and cable assemblies for both gasoline and electric vehicles. This includes the vehicle's battery, main control unit, and turn signals and displays.
• Medical: Cables and wiring harnesses keep patients safe by providing quick connections and are installed in facilities such as imaging equipment, MRI machines, x-rays, electronic beds, and dental chairs.
• Telecommunications: Contains tens of thousands of cables, all of which must be organized to save space and make identification easier. Assemblies serve this role, bundling cables for modems, routers, and similar communications equipment.
• Information technology: cable bundles and cable assemblies save space in small laptops and organize the thousands of cables in a network facility.
• Construction: Wire harnesses are used to insulate and organize electrical wiring in residential and commercial buildings in compliance with all relevant codes.
• Manufacturing: Wire harnesses keep facilities safe by holding wires and ensuring reliable connections in machines such as computer numerical control (CNC) units, three-dimensional (3D) printers, and traditional workstations that require extensive wiring.
• Robotics and automation: Requires tidy (often space-limited) and durable wiring to function properly, so wiring harnesses are needed to route and contain circuits.

Our organization, which has been supporting businesses across all sectors for years through a wide range of testing, measurement, analysis, and evaluation activities, has a strong team of employees who closely follow global developments in science and technology and are constantly improving themselves. In this context, we also provide testing services to businesses in accordance with the "IPC/WHMA-A-620E Requirements and Acceptance for Cable and Harness Assemblies" standard.