The factory acceptance test (FAT) refers to the functional test that is performed by the vendor upon completion of the manufacturing process to prove the equipment has the same specification and functionality that indicated in the datasheet, specification and purchase order.
The test typically is witnessed by the third party inspector and customer representative (purchaser). The term of “factory acceptance test” are used by vendors rather than customers and is implied for electrical, rotating and skid mounted units. We never use this term for fixed equipment such as pressure vessels, heat exchangers, etc.
Normally pump performance test, net positive suction head test (NPSH Test) and mechanical running test are done in one visit and can be categorized as FAT test. Obviously, the pump casing inspection, impeller, and rotor dynamic balancing test are done before FAT Test.
Compressor performance test and mechanical running test are done on the same day and can be considered as a FAT test. Obviously, casing inspection, impeller and rotor "high speed test" and dynamic balancing test are done prior to the FAT test.
Turbine performance and mechanical running test can be considered as turbine FAT test.
The routine test, winding resistance test, locked rotor test, temperature rise test, load test, etc. can be considered as induction motor FAT test.
Several inspection visits are performed before reaching to the FAT test and generally 1 more visit is conducted after FAT test for Final inspection. In the final inspection, the equipment is subjected to the dimensional inspection, visual inspection (coating included), and document review.
For document review, the third party inspector shall check the "inspection and test plan" against the final book. Any item that being marked "review" at the ITP should have an inspection report or test report on the "final book."
The manufacturer provides FAT test procedure to the customer for approval. The inspector shall review the procedures and make sure the FAT test is done based on the approved version of the test procedure.
The manufacturer provides FAT test report upon completion of the test. It is the inspector responsibility to review the test report and match measured value against acceptance criteria indicated in the approved procedure or datasheet. .