FAT vs SAT: acceptance testing for machinery
Agree how equipment will be proven before you sign the contract.
What is the difference between FAT and SAT?
The difference is where, when and against what conditions the equipment is proven. FAT happens at the supplier's works before shipment, usually with simulated or limited product. SAT happens after installation in the buyer's plant, with real utilities, upstream and downstream equipment, product and operators.
Use FAT to catch build, control and safety problems while they are cheap to fix. Use SAT to prove the installed performance the contract promises. Passing FAT does not prove site performance, and SAT cannot recover the time lost when a defect that FAT should have caught is found on site.
- Location — FAT: supplier's factory; SAT: buyer's site
- Timing — FAT: before shipment; SAT: after installation and commissioning
- Conditions — FAT: simulated or sample product; SAT: real product, utilities and line integration
- Typical sign-off — FAT: release for shipment; SAT: handover and final payment milestone
What does a factory acceptance test check?
FAT is the last chance to find problems cheaply, before crating and shipping.
- Mechanical build and documentation against the specification
- Control logic, safety functions and alarms
- Dry runs or test runs with representative material where possible
- Agreed punch list before release for shipment
What does a site acceptance test check?
SAT confirms installed performance: output rate, quality, utility consumption and integration with upstream and downstream equipment, measured under conditions agreed in advance.
What should the RFQ say about acceptance?
- Test location, duration and who attends
- Measurable criteria: output, reject rate, uptime, consumption
- Materials the buyer must supply for testing
- Link between acceptance milestones and payment
- Remedies if criteria are not met
Packaging lines, production lines and calculators
Global B2B Group's main line is packaging and production lines — for fish, shrimp, greenhouse produce and other agri-food products — plus custom machinery, for projects from USD 250,000 with human review before any supplier outreach.
Packaging and production-line guides
- How to compare food packaging line proposals
- Food processing line planning: hygiene, capacity, packaging
- Packaging automation ROI
- Fish & shrimp packaging line profile
- Special-purpose and custom machinery
- Industrial machinery and production lines
Estimate before you send an RFQ
Sector projects go to our specialist platforms
Sector projects such as cold rooms, hatcheries, fish farms, greenhouses or feed mills go to the matching specialist platform. Packaging lines, custom machinery, multi-sector projects, CAPEX planning and financing preparation stay with Global B2B Group, so each buyer has one route and the platforms never compete.
- ColdMatch Group — Cold storage, refrigeration and cold-chain infrastructure
- HatchMatch Group — Poultry farms, hatcheries and poultry infrastructure
- FishMatch Group — Fish farming, shrimp farming and aquaculture systems
- SeedMatch Group — Greenhouses, irrigation, protected agriculture and seed
- FeedMatch Group — Animal feed, ingredients and feed mills
Quick questions
Can SAT replace FAT?+
Not safely for custom or high-value equipment. SAT runs after shipping and installation, so any defect found then costs more time and money to correct. Skipping FAT is a risk decision the buyer should take explicitly.
Is there a standard for FAT and SAT?+
For automation systems in the process industry, IEC 62381 describes FAT, site acceptance and integration testing. Many machinery contracts use it as a reference, but the project's own written acceptance criteria still govern.
Is FAT always required?+
It is strongly recommended for custom or high-value equipment. For standard catalogue items, a documented test report may be sufficient.
Who pays for FAT travel?+
It is negotiable. State it in the RFQ so all suppliers quote on the same basis.
Can payments be tied to FAT and SAT?+
Yes. Many contracts link a payment milestone to successful FAT and the final milestone to SAT sign-off.
Why does a packaging line need both FAT and SAT?+
FAT proves the machine works at the builder's site; SAT proves it works on your floor with your product flow, utilities and operators. Speed and accuracy can change once the line is integrated, so both should have measurable criteria.
Summary
- FAT proves the machine at the factory; SAT proves it in your plant
- Define measurable acceptance criteria in the RFQ
- Link milestones and remedies to test results
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.
Continue with our commercial resources
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