FAT for custom machinery: what to test and when to pay
A custom machine has no track record. The factory acceptance test is where you prove it works before it ships.
Short answer
Why is FAT more important for custom machines?
Standard machines have references running the same model. A custom machine is often the first of its kind, so the FAT is the first real evidence that the design meets your process.
Which criteria should the FAT measure?
Every criterion should be measurable and linked to the requirement in your RFQ.
- Output per hour at the stated product format
- Continuous run time without stoppages
- Reject or defect rate
- Format changeover time
- Safety functions, guarding and emergency stops
- Documentation and software backups delivered
What product should be used for testing?
Send enough of your real product or packaging to run a meaningful test. Tests on substitute material often hide problems that appear on site.
What happens if the machine fails FAT?
The builder corrects the issue and the test is repeated at its cost, within an agreed period. Repeated failure should trigger remedies defined in the contract.
Quick questions
Does passing FAT mean the machine is accepted?+
No. Final acceptance normally follows the site acceptance test (SAT) after installation.
Can FAT be witnessed remotely?+
Remote witnessing is possible for simple checks, but in-person attendance is safer for first-of-a-kind machines.
Who pays for a repeated FAT?+
Normally the builder, if the first test failed against agreed criteria.
Summary
- Agree measurable FAT criteria in the contract
- Test with your real product
- Link the pre-shipment payment to a signed, passed FAT
Global B2B Group is an independent, human-reviewed procurement channel — not a manufacturer, contractor or lender. Figures and methods here are general guidance; confirm project-specific details with qualified advisers.
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