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The GIS consists of a number of interconnected Allen-Bradley GuardLogix safety PLCs that monitor the various subsystems of the facility. The PLCs are connected to various distributed I/O modules in and around the various subsystem. The GIS uses it’s own private ethernet network.
Most of the components of the GIS are designed around a redundant safety architecture. In this design, the redundancy is used to ensure safety not to allow continued operation in the event of failure. A component failure results in the system transitioning to a safe, albeit non-operational condition.
The two most recognizable parts of the GIS are the emergency stop devices and the trapped key system.
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