| Quality management system | A documented quality management system aligned with ISO 9001:2015. | Valid certificate showing the legal entity, certification scope, issue date, expiry date, and certification body. | Certificate details match the contracting entity and can be confirmed through the certification body or its public register. | Critical |
| Certificate scope | The ISO 9001 scope should cover activities relevant to encoder manufacturing, assembly, testing, or distribution. | Complete certificate scope and certificate number, with any applicable site addresses. | Reject certificates that cover only unrelated activities or a different site from the proposed production location. | Critical |
| Certification validity | The certificate must be current at the time of supplier approval and purchase order release. | Current certificate, surveillance or recertification status, and certification-body contact or verification link. | Record the verification date and schedule a recheck before certificate expiry. | Critical |
| Ingress protection claim | Any IP rating must be stated in the form defined by IEC 60529, such as IP54 or IP65, and must apply to the tested product configuration. | Test report identifying the product, enclosure configuration, test laboratory, test date, and applied IP code. | Do not treat an unverified marketing statement as proof of IEC 60529 compliance. | High |
| IP code interpretation | The first IP digit addresses protection against solid foreign objects; the second addresses protection against water. | Product datasheet and test report using the same IP code and product revision. | Confirm that the claimed protection level matches the buyer's environmental application and installation conditions. | High |
| Product identification | Each shipment should be linked to a defined part number, revision, quantity, and production lot. | Packing list, product label, inspection record, and purchase-order cross-reference. | All documents use consistent part numbers and revision levels without unexplained substitutions. | Critical |
| Lot traceability | The supplier should be able to trace finished goods to a production lot and relevant manufacturing records. | Lot number, manufacturing date, work order, operator or station record, and final inspection result. | Perform a sample trace from shipment record back to production documentation within an agreed response time. | Critical |
| Component traceability | Critical components should be linked to approved suppliers, incoming inspection, and applicable batch information. | Approved supplier list, incoming inspection report, component batch record, and nonconformance history. | Verify that changes to critical components require documented approval before use. | High |
| Calibration control | Measurement equipment used for acceptance testing should be identified and maintained in a controlled calibration system. | Equipment register, calibration certificates, due dates, and out-of-tolerance evaluation records. | No critical test result should rely on equipment with expired or unresolved calibration status. | High |
| Final inspection | Finished products should be checked against agreed electrical, mechanical, dimensional, and visual requirements. | Inspection plan, sampling method, test results, acceptance criteria, and authorized release record. | Confirm that test records identify the actual lot and product revision supplied to the buyer. | Critical |
| Change management | Design, material, process, site, or subcontractor changes should be reviewed and communicated before implementation. | Engineering change procedure, change notification form, approval record, and validation evidence where applicable. | Require written notification for changes that may affect fit, form, function, reliability, or compliance. | High |
| Nonconforming product control | Nonconforming products should be identified, segregated or controlled, dispositioned, and recorded. | Nonconformance reports, corrective-action records, rework approvals, and concession records. | Review recurring defects and confirm that corrective actions address root causes. | High |
| Record retention | Quality and traceability records should be legible, retrievable, protected from unauthorized changes, and retained for an agreed period. | Document-control procedure, retention schedule, access controls, and sample archived records. | Agree the retention period contractually before qualification and confirm records can be retrieved during an audit. | High |
| Pre-shipment verification | The buyer should verify documents before shipment rather than relying only on supplier declarations. | Commercial invoice, packing list, certificate of conformity, inspection report, and approved sample reference. | Release shipment only when product identity, quantity, inspection status, and traceability references agree. | Critical |