Testing Is Not One Thing
“We test every unit” is a phrase that can mean almost anything. It is worth setting out precisely what is tested, at which stage, and what a failure at each stage tells you — because a buyer who knows the difference can tell whether a supplier is describing a process or repeating a slogan.
What Is Tested, and When
| Stage | What is checked | What it catches |
|---|---|---|
| Component input | Lot verification and specification check | A wrong component, caught before it reaches the line |
| In-process | Line check on the assembled board | Drift caught while it is still cheap to correct |
| Final functional | 100% of units tested against function | Every unit that does not work never leaves the factory |
| Pre-shipment sampling | AQL 5% third-party inspection | Cosmetic, labelling and packing issues |
Why 100% Functional Test Is Not the Same As 100% Quality
A functional test answers one question: does this unit perform its function? A garage remote either transmits the correct code at the correct frequency, or it does not. A contactor either pulls in and holds, or it does not. Those are binary, measurable, and cheap enough to test on every single unit, which is why we do it on every single unit.
Functional testing cannot see a cosmetic defect, a slightly wrong label, a housing that is 0.5mm proud, or the wrong part in the box. That is what sampling inspection at AQL 5% covers, and the two controls solve different problems. A supplier offering only the first has process control but not packing control. A supplier offering only the second is inspecting somebody else’s work.
The two controls belong together: functional testing catches the unit that does not work, sampling inspection catches the unit that is not what was ordered.
What a Failure Means at Each Stage
| Failure point | Most likely cause | What happens |
|---|---|---|
| Component input | Out-of-spec part or wrong reel | Lot quarantined, supplier notified |
| SMT / assembly | Solder defect or placement error | Line stopped, board revision reviewed |
| In-process check | Drift before it reaches a finished unit | Cheapest point to catch it, so it is corrected here |
| Final functional test | Component or assembly defect | Unit removed, batch checked, cause traced |
| Pre-shipment sampling | Cosmetic, labelling or packing issue | Re-pack or re-label before it leaves |
Request a Quotation — Our Quality Control Process
Send the product line and target market. We reply with a written EXW quotation, MOQ, lead time, a sample offer and the QC documentation that ships with the batch. MOQ 100 pcs per SKU.
Send Inquiry on WhatsAppEmail: Joanna@rfmando.com · MOQ 100 pcs per SKU · 1 free sample per SKU ($30 DHL, buyer pays) · Lead time 7-15 days · T/T 30/70 · EXW Xiamen
Catalogue references for the specification above: TY200 4-band multi-frequency cloner and DILM7-01 110VDC contactor. Both are MOQ 100 pcs per SKU, with a 7-15 day lead time and one free sample per SKU. They are supplied on our own PCBA and housing tooling.
Terms
MOQ 100 pcs per SKU. One free sample per SKU ($30 DHL, buyer pays). Lead time 7-15 days. Payment T/T 30/70. Prices EXW Xiamen. 100% functional test on every unit; a third-party QC report at AQL 5% is available on request. CE-RED, RoHS and FCC Part 15 documentation; RCM available.