Overview
IPC/WHMA-A-620 is the industry consensus standard for requirements and acceptance criteria for cable and wire harness assemblies. It is the document that assemblers, inspectors, and design engineers use to decide what is acceptable, what must be reworked, and what must be rejected for Classes 1-3 builds including high-reliability aerospace and defense work.
I pursued the Certified IPC Specialist (CIS) credential to do more than just “know of” the standard. I wanted to be comfortable opening the book, finding the right figure or table under time pressure, and speaking the same workmanship language as the technicians and inspectors on the shop floor. I also enjoy hands-on assembly work and wanted a structured way to connect that with my electrical engineering background instead of living purely in schematics and CAD all day.
Core Competencies
- Interpreting IPC/WHMA-A-620 Class 1-3 acceptance criteria for cable and harness assemblies, including how to quickly navigate modules, figures, and tables during real inspections.
- Understanding workmanship requirements for crimped contacts, soldered terminations, insulation support, shielding, splices, coax/biax, and protective coverings.
- Identifying defects versus acceptable conditions (e.g., conductor exposure, nicked strands, voids, inadequate wetting) and deciding whether a joint is acceptable, reworkable, or a reject.
- Applying documentation and traceability practices so harness builds can be audited, reproduced, and tied back to specific revision levels of the standard.
- Communicating with assemblers, inspectors, and design engineers using a shared vocabulary grounded in IPC/WHMA-A-620 instead of informal or tribal workmanship rules.
Training & Exam
I completed a three-day, in-person IPC/WHMA-A-620 CIS course at Verion Training Systems in early November 2025, followed by an additional hands-on day focused on the workmanship modules. The class was intentionally small, just myself and one other student, so the instructor could spend more time on questions, edge cases, and real-world examples drawn from production cable and harness work.
Over the lecture days, we stepped through all eight general knowledge modules, covering topics like applicable documents, crimp and IDC terminations, soldered terminations and high voltage, connectors, molding/potting, ultrasonic welding and splices, marking and securing, coax/biax, and full harness construction. Each module finished with an open-book exam keyed directly to the standard; I passed every exam with scores above the required 70 percent to achieve the CIS designation.
The optional hands-on day was my favorite part of the course. I spent the day building and inspecting real terminations across the associated workmanship modules (H1-H6), then comparing my work to the acceptance criteria in the book and the instructor's reference samples. That combination of “book in one hand, crimp tool or soldering iron in the other” really locked in what the figures and tables actually mean on a real assembly.
Practical Application
For me, this certification is about bridging design and manufacturing. When I'm working on harness drawings, reviewing vendor documentation, or walking a production floor, I want to be able to look at a crimp, splice, or shield termination and evaluate it against an objective standard, not just “what looks good.” IPC/WHMA-A-620 gives that objective bar, and the CIS training gave me reps actually using it.
In practice, that means:
- Being able to open the standard and quickly answer questions like “Is this much conductor exposure acceptable for Class 3?” or “How should this shield termination be dressed and supported?”
- Reviewing harness and cable drawings with a better sense of what's realistic and buildable on the bench, and where additional notes or callouts will help technicians hit the right workmanship level.
- Feeling comfortable jumping into harness, and wiring-focused roles (or shop-floor discussions) where IPC language and examples are the reference point for quality.
Long term, I see this as a foundational credential for doing more work that lives at the intersection of schematics, harness design, and hands-on assembly-being just as comfortable at the bench as I am inside a CAD tool or a Python script.