IEC 62381:2024 defines the factory acceptance test (FAT) as an activity to demonstrate that the automation system is in accordance with the specification, typically conducted at the vendor's facility, and the site acceptance test (SAT) as an activity to demonstrate, at the site of the installation, that the installation is in accordance with the applicable standards, codes, specifications, and installation instructions. The two tests differ not only in location but also in what they demonstrate, and the 2024 edition adds the optional factory integration test (FIT) and defines requirements and checklists for the FAT, FIT, SAT, and site integration test (SIT). Loop checks and commissioning lie outside the scope of…