Company / Project Profile
- Stena Clyde Drilling Rig
- Self-propelled, semi-submersible drilling unit
- Gas detection system for Flammable and Toxic (H2S) gas
- Three separate controllers combined within one enclosure to provide common controls for Plant shutdowns
It was determined that a series of controllers were required, built into one consolidated system to facilitate the system's alarm response, in the event of a gas alarm.
The clients’ expansion has resulted in not only an increased demand for gas detection circuits, but there was now a reassignment of detector circuits between certain Plant areas. This meant, in real terms, that the system expansion could not be achieved by simply adding another controller as completely separate controllers did not allow for the necessary interaction between alarm signals from each of the areas.
In order to provide the additional gas detector circuits and a common alarm response control it was determined that a series of controllers were required, built into one consolidated system to facilitate the system’s alarm response, in the event of a gas alarm.
However, with space in the control room at a premium, the extra capacity required in the control system would have to be achieved within a smaller footprint than that of a “multiple” of standard controllers.
To achieve the required number of control circuits within the space allowed, the standard controllers were de-constructed and reassembled within a proprietary wall mounting enclosure where it became much easier to configure those sections of the systems that were shared by each of the separate area controllers – 24v DC power supply, common manual controls for alarm acknowledgement and silence, common outputs for shut-down and indication to third-party systems.
As part of the project existing wiring schematics for the Plant alarms and shut-down signals were updated to reflect how signals were now configured within the new, bespoke system.
A complete new set of wiring schematics, cause & effect drawings, and termination diagrams, together with an Operating & Maintenance manual for the new system were provided as part of the documentation package.