MACRO Sensors has released a range of hermetically-sealed position sensors for use with steam control valves in power generation plants.
The HSTAR 750 Series Position Sensors are constructed from stainless steel and can operate in high temperature environments up to 204 degrees Celsius.
The company says the units can provide highly accurate position feedback of different valves to remotely located control systems.
According to the manufacturer, a typical two-stage steam turbine can contain a number of control valves, including a governor valve, a throttle valve, an interceptor valve and a reheat stop valve. All of which are operated by hydraulic actuators.
It is very important to know the position of the governor and throttle valves, because they are modulating valves whose steam flow is critical to the efficiency of the turbine. It is also important to know if the interceptor and stop valves are closed.
The company says the units can signal an operator if anything is not working properly.
According to the manufacturer, the devices feature a high resolution, excellent repeatability and low hysteresis. They are available in ranges from 1.25 to 250mm.