Measurement and control for fluid flow valve position - is performed by logic circuit permitting energy consumption calculation

摘要

The operation of a valve in a fluid flow is controlled and measured in order to provide control and measurement of energy consumption. The position of a valve (14) in a fluid flow (12) is measured and controlled (18, 20, 22, 32) by a logic programming circuit (26) to which a position sensor (48) is connected via a multiplexer. Temperature sensors (40, 42) measure temperature of the fluid inlet and outlet flow in order that energy loss may be calculated for control of valve when compared with predetermined value. Fully closed and fully open valve positions are indicated and intermediate positions determined from a control low curve to permit control of fluid flow.