What Is IPC/WHMA-A-620 and Why Is It Important for Manufacturing?

If you work in the electronics, aerospace, or automotive industry, you may have come across IPC‑A‑620. This standard is essential for ensuring wire and cable harnesses are built right, whether for high‑reliability aerospace systems, industrial machinery, automotive electronics, or consumer devices. 

Understanding the key FAQs about IPC‑A‑620 can help reduce defects, save time, and ensure consistent quality across your products.

Here are the most common questions about IPC‑A‑620 answered in a practical, easy-to-understand way.

What exactly is IPC‑A‑620?

IPC‑A‑620 is the industry standard for requirements and acceptance of cable and wire harness assemblies. It defines how wires, cables, connectors, crimps, and soldered connections must be made and inspected to meet industry-wide quality expectations. 

Why is IPC‑A‑620 important for manufacturers?

It ensures assemblies meet consistent quality and reliability requirements. High-quality wiring is critical for many industries. IPC‑A‑620 helps prevent costly recalls, equipment failures, and safety risks in everything from aircraft wiring to medical equipment to industrial controls.

What does IPC‑A‑620 cover in practice?

IPC-A-620 lays out clear expectations for how cable and wire harness assemblies should be built, bundled, routed, and checked. It addresses everything from wire prep and crimping to soldering, labeling, shielding, terminations, and final testing. The standard also includes visual examples that help inspectors make consistent, fair decisions, regardless of industry or application.

What are the different quality classes in IPC‑A‑620?

There are three classes of acceptability depending on product use and reliability needs. IPC-A-620 defines three acceptance classes to match different performance needs. Class 1 applies to general electronic products. Class 2 is intended for assemblies that must deliver extended service life under normal operating conditions. Class 3 is used for high-reliability applications such as aerospace systems, medical devices, and military electronics.

At Spartronics, we adhere to IPC-A-620 standards to ensure the highest quality in electronic assemblies, tailored to your specific application. IPC class standards define the level of acceptability for electronic products, helping manufacturers, designers, and end-users understand the quality and reliability expectations for each product.

Class 1 – General Electronic Products:

Class 1 is intended for electronic products where basic functionality is the primary concern. These are typically consumer electronics, commercial devices, or other applications where occasional cosmetic imperfections are acceptable, provided the device operates as intended. Spartronics ensures that all Class 1 assemblies meet functional requirements, maintaining consistent performance while optimizing manufacturing efficiency for high-volume production.

Class 2 – Dedicated Service Electronic Products:

Class 2 assemblies are designed for applications requiring extended service life under normal operating conditions. This includes industrial machinery, telecommunications equipment, and other systems where reliability and longevity are essential, but occasional downtime may be tolerable. Spartronics applies enhanced quality control measures, including stricter soldering standards and thorough inspection processes, to ensure that Class 2 products deliver durable performance over their expected lifespan.

Class 3 – High-Reliability Electronic Products:

Class 3 is reserved for critical applications where failure is not an option, such as aerospace systems, medical devices, military electronics, and other mission-critical technologies. These assemblies must perform reliably under harsh conditions, including extreme temperatures, vibration, and long operational hours. Spartronics adheres to the highest inspection and testing standards for Class 3 assemblies, employing rigorous process controls, advanced inspection equipment, and detailed documentation to ensure every product meets the stringent requirements of high-reliability applications.

Are there additional requirements for military and space applications?

Assemblies built for military and space environments often must meet even stricter requirements beyond standard IPC-A-620 Class 3. For these applications, manufacturers may need to follow the IPC-A-620 Military & Space Addendum, which addresses the extreme conditions these assemblies are subject to. This addendum includes enhanced criteria for artistry, materials, and inspection to account for intense thermal cycling, extreme temperature swings, shock, and high vibration that are common in launch, flight, and defense environments.

These added requirements help ensure wire and cable harnesses maintain electrical and mechanical integrity over long mission lifespans, where repairs may be impossible, and failure could have serious consequences. For manufacturers serving defense, aerospace, or space programs, understanding and applying the Military & Space Addendum is critical to meeting contract requirements and delivering assemblies that perform reliably under the harshest conditions.

Does certification matter for my team?

IPC‑A‑620 certification ensures your team applies the standard correctly. Training programs such as CSE (Certified Standards Expert) equip personnel to interpret, build, bundle, and inspect assemblies to the standard accurately. Certified staff reduce inspection errors and improve overall quality.

Can IPC‑A‑620 reduce defects on the line?

Absolutely, IPC‑A‑620 standardizes criteria so issues are caught early. Using measurable acceptance standards and visual guides helps reduce scrap and rework rates across industries, from automotive electronics to industrial automation to aerospace wiring systems.

Do we still need IPC‑A‑620 if we follow ISO standards?

IPC‑A‑620 complements ISO quality systems such as ISO 9001 and ISO 13485. While ISO defines overall quality management requirements, IPC‑A‑620 provides practical, process-specific guidance for cable and harness assembly work. This combination ensures regulatory compliance and consistent product quality.

Is IPC‑A‑620 still being updated?

The standard evolves to reflect industry consensus and technological advances. Latest revisions include expanded guidance on crimping, soldering, labeling, inspection methods, and new materials. Keeping revision standards up to date ensures your assemblies meet current industry expectations.

How does IPC‑A‑620 benefit OEMs and contract manufacturers?

It creates a shared quality language between OEMs and manufacturers. By referencing the same acceptance criteria, both parties reduce misinterpretation, avoid disputes, and build confidence in delivered assemblies. This is especially important in contract manufacturing across automotive, aerospace, medical, and industrial electronics sectors.

Using IPC‑A‑620 in manufacturing goes beyond compliance. It builds reliability, reduces defects, and strengthens your team’s confidence in their work. Whether you operate in aerospace, automotive, medical, defense, or industrial electronics, this standard ensures your assemblies meet global quality expectations.
 

Want to improve assembly quality and consistency? Explore IPC‑A‑620 training and certification to give your team the skills they need to deliver reliable, high-quality products every time.