Safety Instrumented System (Sif) - GE Mark VIe System Manual

2.1 Safety Instrumented System (SIF)

While the Safety controller performs the logic solving tasks for the system, it also interfaces with the ToolboxST application
for configuration, diagnostics, and changes to controller application logic (blocks). The ToolboxST application provides a
means to lock or unlock the Safety controller for configuration and safety-instrumented function (SIF) programming. This
allows the user to install a safety function, test it, and place the controller in Locked mode to perform safety control.
Sensors
Interfaces to Mark VIeS Safety controller must be strictly regulated to avoid interference with the operation of the system.
Data exchange to the safety control must be restricted and only used when validated by the SIL application logic.
The Mark VIeS Safety control was designed and certified to meet functional safety standards according to IEC 61508 Parts 1
through 3. It is certified for use in both high-and low-demand applications, uses redundant architecture configurations, and a
hardware fault tolerance (HFT) of 1 to achieve safety integrity level (SIL) 3. The highest achievable SIL with an HFT of 0 is
SIL 2.
IEC 61508-4 definitions are as follows:
Safety Freedom from unacceptable risk.
Risk Combination of the probability of occurrence of harm and the
severity of that harm.
Functional Safety Part of the overall safety relating to the equipment under control
(EUC) and the EUC control system that depends on the correct
functioning of the Electrical/electronic/programmable electronic
(E/E/PE) safety-related systems, other technology safety-related
systems, and external risk reduction facilities.
68 GEH-6721_Vol_I_BP
Third-party
devices
Safety Controller
Logic Solver
Safety Instrumented System
GEH-6721_Vol_I Mark VIe and Mark VIeS Control Systems Volume I
WorkstationST OPC Server
Locked/Unlocked mode
Public Information
Final Elements