Electronics Factory Verification in China

SMT and assembly claims

A supplier claiming in-house SMT should be able to show placement machines, reflow ovens, stencil handling and a line running. What is often found instead is a company that performs final assembly and box-build in-house and buys populated boards from a neighbouring supplier. That is a normal and workable arrangement — the problem is only that it was not disclosed.

• Count the lines, and ask which are running and for whom.
• Ask where boards are populated if no SMT line is visible.
• Ask whether the line you are shown would run your product.

Testing equipment and what its presence means

AOI, ICT, functional test fixtures, ageing racks and calibration records are all visible during a walkthrough. Their presence tells you the supplier has invested in test capability. It does not tell you the tests are run on every batch, that fixtures exist for your product, or that failures are actioned rather than reworked out of sight. Ask what the first-pass yield is and how failures are recorded.

Component traceability

For anything with a safety, longevity or certification dimension, ask how incoming components are recorded and how a batch would be traced if a field failure occurred. Counterfeit and re-marked components are a real risk in some channels, and the supplier’s answer about approved-vendor lists and incoming inspection is informative regardless of what the paperwork looks like.

Certifications are documents, not processes

A CE, FCC, UL or RoHS document describes a test performed on a sample at a point in time under a defined scope. It does not establish that current production matches that sample, and certificates are among the most frequently altered documents we see. Where a certificate matters to your market access, verify it with the issuing body and test the production units — do not rely on a PDF from the supplier.

ESD and quality areas visible during a visit

ESD flooring, wrist straps actually worn, ionisers, a controlled quality room, and whether operators follow the controls when nobody is prompting them — these are all visible and all meaningful. A factory that has the equipment but does not use it is telling you about its quality culture more reliably than any certificate.