Inspection and testing approach

Testing against the requirement

Inspection and testing exist to show that the supplied equipment matches its agreed configuration. Invitrona plans them around the requirement and the configuration, not as a fixed routine applied identically to every product.

Stages of inspection

Inspection takes place at several points:

• Incoming material: checking that purchased materials and components match their specification before use
• In-process: checks at defined stages of assembly, where faults are easier to find and correct than in a finished unit
• Final inspection and testing: checks of the finished unit against its configuration before dispatch

The checks at each stage depend on the product family. A transformer, a rectifier and an LED driver are verified in different ways because their risks are different.

What a test plan states

For equipment where the project defines verification, a test plan is agreed before manufacture. It states:

• Which tests are performed and at which stage
• The method, instruments and conditions for each test
• The acceptance criterion for each result
• Which tests, if any, the customer will witness
• Which records are supplied, and when

Where a specification names a standard for testing, the test plan states how the tests relate to it. A standard named in a specification is a requirement to be addressed, not a claim made in advance.

Witness inspection

Where a project requires it, the customer or their representative can witness agreed tests. The visit is planned with the unit identity, the test plan and the documents ready, so that the inspection reviews the actual equipment and method.

Records

Results are recorded against the unit's identity. Inspection and test records for supplied units are available on request. Where a result does not meet its criterion, the unit is held and the nonconformity is handled through the deviation process described in handling deviations.

Instruments and conditions

A test result means little without its method. Test records identify the instruments used and the conditions of the test, such as the input voltage, the load applied and the ambient temperature, so that a result can be understood and, where necessary, repeated. Where a test cannot reproduce site conditions at the works, for example a full process load on a large rectifier, the test plan says what is tested at the works and what is confirmed during commissioning.

Questions you can ask

• Which tests apply to this configuration, and which are performed at commissioning instead?
• What are the acceptance criteria for each test?
• In what form are the records supplied, and how are they linked to the serial number?

What this means for a buyer

You can ask before ordering which inspections and tests apply to your configuration, how they are performed and what records you will receive. Agreeing this at the start avoids a dispute at dispatch.