Abstract: A method and apparatus or arrangement, for monitoring the operating characteristics of valves, principally to monitor for failure of a valve. The method including measuring a pressure differential across a valve 1 and comparing the measured differential with a required differential. If the measured differential is acceptable relative to the required differential, the valve is deemed to be operating acceptably. If the differential is not acceptable relative to the required differential, then further monitoring in the form of flow sensing takes place and is compared relative to required flow characteristics. The method employs a comparison of the pressure differential and the sensed flow characteristics to determine whether the valve is operating acceptably.

Abstract: A transducer is disclosed for sensing flow of a fluid. The transducer includes means for applying a heat pulse to the fluid and at least one temperature sensor. The temperature sensor is adapted to detect a decaying response to the heat pulse to provide an indication of the flow. The decaying response may be detected by comparing measured voltages at a set moment in time or by comparing measured times at a set voltage threshold. A method for sensing flow of a fluid is also disclosed.