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The Design of a Pneumatic Pressure Reference Source with Automatic Control

The design of a pneumatic pressure reference source with automatic control is described. The design is based on the accuracy and reliability of the well known dead weight tester and a piston position transducer is incorporated with a precision pressure controller to form a closed loop system. A linearised analysis is used to show the complexity of the system dynamics and give some indication of the stability criteria. A prototype model was built, tested and the results are discussed. Conclusions are drawn that suggest the system is feasible and worthy of further development.