How to Select and Validate an Automatic Coil Testing Machine

Begin with the approved test plan

An automatic coil testing machine is only as useful as its limits and methods. Define which characteristics protect product function: continuity, winding resistance, inductance, polarity, insulation or other component-specific tests. State the test conditions and source of every limit.

Separate laboratory qualification from production screening. The production test must be fast and repeatable enough for the line while still detecting the failure modes that matter.

Design stable contact and part handling

Contact variation can look like product variation. Fixtures should locate the coil positively, reach terminals without damage and apply controlled probe travel. Include probe cleaning, wear limits and a verification routine using approved reference parts.

An inductor testing machine may use bowl feeding for repeat components; transformer and relay testing may require different nests and orientation checks. Feeding choice should never compromise terminal access or part protection.

• Part-present and orientation checks
• Contact-force and probe-life plan
• Golden-sample verification
• Secure pass and reject paths

Control recipes, retest and traceability

The product recipe should select the correct measurement sequence and limits. Access control reduces accidental changes, while fixture or barcode identification can prevent the wrong program from being used.

Define whether a failed component may be retested, who can authorize it and how results are stored. Automatic reject handling should prevent a failed or untested part from mixing with accepted output.

Validate measurement and production behaviour

Compare the automated system with the approved reference across good, marginal and known-failed samples. Study repeatability, fixture-to-fixture variation, temperature influence and contact contamination. Then run at target cycle with normal feeding and reject events.

PME offers automatic inductor, relay, transformer and combined testing systems. The suitable model depends on the component, parameters, handling method, line rate and traceability requirement.