- August 23, 2017
- Emerson Automation Solutions
August 23, 2017 - Emerson’s water and steam detection system was certified to IEC 61508 for safety instrumented functions up to SIL 3. The Mobrey Hydratect 2462 Water and Steam Detection System is used in a variety of applications where the detection of water or steam is vital for safe and efficient plant operation, such as boilers, steam drums and steam line drain pots.
Exida, world leaders in functional safety certification, have assessed Hydratect and determined that it meets the requirements of SIL 3. The Hydratect system is ideal for the demanding applications within power generation, refineries, chemical, steel, pulp and paper plants. It can operate in process conditions of up to 300 bar and 560°C. Failure of equipment in such applications can have serious consequences – the Hydratect offers the benefit of SIL 3 approval.
Hydratect is a modern replacement for conventional float switches, and consists of a twin-channel electronic unit, connected to a pair of electrodes. Each channel gives independent indications of the presence of water or steam that are more reliable than those obtained with electro-mechanical devices, which have the possibility of failing in an unsafe condition. By installing the electrodes in vessels or steam lines and measuring the resistance, the presence of water can be detected, allowing appropriate safety measures to be taken.
By detecting low water level in steam drums, Hydratect helps to prevent boiler tubes overheating, which could lead to an explosion, while detecting high water level prevents the generation of wet steam which could cause costly turbine blade erosion. Using Hydratect to detect water in steam line drain pots, as part of a turbine water induction prevention system (TWIP), helps prevent damage to turbine blades, cylinders and the housing.
The electronics unit provides a local indication of steam, water and fault states, and features configurable fault and trip outputs. Component failure, cable faults, ground faults and electrode problems are continuously self-monitored. Additional reliability is provided by triple redundancy of critical components, which ensures that failures result in a safe condition.