SAT
System Acceptance Tests
SAT (System Acceptance Tests) are formal tests conducted to demonstrate that an installed railway system satisfies specified functional, performance, interface and operational requirements and is acceptable for its intended use.
Detailed explanation
SAT – System Acceptance Tests are structured tests undertaken during the testing, commissioning and acceptance stages of a railway project to verify that a system, subsystem or equipment performs as required after installation and integration.
Unlike a Factory Acceptance Test (FAT), which is normally carried out at the manufacturer’s or supplier’s facility before equipment is delivered to site, SAT is generally performed on the installed system in its actual or representative operational environment.
SAT may verify areas such as:
Functional performance against approved requirements and specifications
Interfaces between railway systems and subsystems
Communications and data exchange
Failure, degraded and recovery modes
Alarm and event reporting
Control and monitoring functions
Performance under representative operating conditions
Safety-related functionality where applicable
Compliance with agreed acceptance criteria
Resolution of outstanding testing and commissioning issues
For an integrated railway, SAT can involve systems such as signalling, telecommunications, traction power, SCADA, OCS/OLE, platform screen doors, AFC, depot systems, station systems and rolling stock.
SAT typically forms part of the wider Verification & Validation (V&V) and Testing & Commissioning process. Successful completion provides documented evidence that the system meets the defined acceptance requirements before progression to subsequent stages such as integrated testing, trial operations, operational readiness or final acceptance.
FAT → Installation → Site/System Testing → SAT → Integrated Testing → Trial Operations / Acceptance
Standards and references
IEC 62278 – Railway Applications – RAMS
IEC 62279 – Railway Applications – Software for Railway Control and Protection Systems
IEC 62425 – Railway Applications – Safety-Related Electronic Systems for Signalling
EN 50126 – Railway Applications – RAMS
EN 50128 – Railway Applications – Software for Railway Control and Protection Systems
EN 50129 – Railway Applications – Safety-Related Electronic Systems for Signalling
ISO/IEC/IEEE 15288 – Systems and Software Engineering – System Life Cycle Processes
ISO/IEC 17025 – General Requirements for the Competence of Testing and Calibration Laboratories