A new on-line calibration system for safety valves in power plants based on ARM and ethernet technology has been developed

mainly including signal regulation

data acquisition

and embeded processing system.The software of ARM data acqiesition unit adopts embeded Linux operating system to carry out development of applied programme for the networks

through interface of ethernet to realize communication with upper computer(PC) to complete on-line calibration of safety valves.The highly accurate pressure transducer and valve stem displacement sensor have been selected

boasting superiority in many aspects

such as algorithm for signal processing

velocity and accuracy in data acquisition

compatibility and expandibility of the interface etc.

can more accurately judge the open pressure of the safety valves

reducing occurrence of errors.