Triple Controller (TMR): Adopting 2oo3 voting logic, it can tolerate single point failures and maintain safety functions.
The controller runs a real-time operating system and supports mixed programming of Function Block Diagram (FBD), Cause&Effect Matrix, and Relay Ladder Diagram (RLD). The controllers synchronize key variables through IONet to ensure disturbance free redundancy switching.
2.2 I/O modules (I/O cards and terminal components)
The Mark VIeS I/O module adopts a three piece design: on-site wiring terminal block, terminal board, and I/O package. This modular structure brings two major benefits:
No need for intermediate relays or isolation terminals, directly connect to on-site instruments, reduce installation costs and minimize potential fault points;
Supports hot plugging and online replacement, and the maintenance process does not affect safety functions.
Each I/O pack is equipped with two IONet ports and a local processor, with a built-in high-precision real-time clock that can provide 1 millisecond resolution sequence of events (SOE) recording for all discrete input-output signals. Users only need to select the corresponding channel in the configuration software to enable SOE, without the need for dedicated hardware, significantly reducing system complexity and costs.
Analog quantity I/O module supports universal configuration. Each channel on the same module can be set as AI or AO independently, reducing spare parts types and cabinet space.
2.3 I/O Network (IONet)
IONet is a deterministic, full duplex, point-to-point communication network designed specifically for security systems, with a transmission rate of 100 Mbps, supporting local or remote cabinet deployment. Within one scanning cycle, the online controller completes the following tasks in parallel:
Read data from the input module;
Write the calculated results into the output module;
Synchronize intermediate variables between controllers in dual machine or TMR configuration.
IONet switches are custom designed for GE Vernova, with wide temperature capability and high anti-interference performance, ensuring uninterrupted communication in extreme environments.
2.4 Virtual Mark VIeS Controller
For the convenience of training, logic verification, and factory acceptance testing, the system provides a PC based virtual controller. This virtualization environment can:
Execute actual application program code;
Communicate with ToolboxST engineering software;
Support Ethernet Global Data (EGD) service;
Simulate process alarm management.
Users can complete most of the logic debugging and simulation without connecting to real hardware, significantly reducing the on-site debugging time of the project.

Flexible redundant architecture: configure SIL levels and availability as needed
One of the most prominent technical features of Mark VIeS is its segmented redundancy design. Traditional security systems typically require all components to use the same level of redundancy, resulting in high costs or excessive local redundancy. And Mark VIeS is based on the Ethernet backbone network, allowing the following parts to independently choose redundancy levels:
Controller: single, dual or TMR;
IONet communication: single, dual, or TMR;
I/O module: single or TMR.
This flexibility allows users to accurately match the actual risk reduction needs of each Safety Instrumented Function (SIF). For example, for the low demand emergency stop function of SIL 2 level, a combination of a single controller, dual IONets, and single I/O can be used; For high demand turbine overspeed protection at SIL 3 level, TMR controller, TMR network, and TMR I/O can be selected.
The specific supported configuration modes include:
TMR 2oo3 SIL 3 high/low demand, used for de energizing to trip during power outages;
TMR 2oo3 SIL 2 low demand, used for energy to trip;
TMR downgrade mode 1oo2 SIL 3: When one channel in TMR fails, SIL 3 capability is still maintained;
TMR downgrade sequence: 2oo3 → 1oo2 → fail safe, ensuring progressive reliability;
Dual machine 1oo2 SIL 3 high/low requirements;
Dual machine 2oo2 SIL 2 low demand, suitable for power on or power-off trip;
Single machine 1oo1 SIL 2 low demand.
The above configuration changes are completely completed during the hardware configuration phase, which is transparent to the application layer code and greatly simplifies project design and later upgrade work.
Software Tools and Engineering Efficiency: Integration of ControlST and exSILentia
An excellent security system not only relies on hardware reliability, but also on efficient engineering software support. Mark VIeS adopts ControlST as a unified configuration, monitoring, and diagnostic platform, and integrates the industry's authoritative exSILentia safety lifecycle management tool.
4.1 ControlST Function
ControlST provides the following core capabilities:
Logic programming: supports three languages: FBD, causal matrix, and ladder diagram, to meet the needs of different engineers;
Library management: supports the establishment of tested and validated OEM algorithm libraries, and can be quickly deployed to multiple projects through advanced replication tools;