The 3D family of variable volume pressure controllers are available for calibration applications of 0-1,000 psi and 0-6,000 psi in absolute or gauge pressure. Both models function as highly sensitive vernier controllers with outstanding adjustment sensitivity: .0005 psi for the V-1R and .005 for the V-2R. Utilizing the principle of expansion or compression of gas by the displacement of a piston, both models can generate up to 50 psi in a static system without requiring an outside pressure source. These pressure volume controllers consist of a volume chamber and an internal piston assembly. Piston movement within the chamber increases or decreases the volume of the system depending on the direction of the piston movement. In a closed system, where trapped gas has no leak path, any volume change will result directly in a change of pressure. The pressure change generated by a given amount of piston travel is proportional to the change in volume as compared to the total system volume. The V-1R and V-2R can also be used without a compressed air source for the generation of positive pressure below 50 psi as well as vacuum. The high resolution of these units, combined with the ability to generate pressure, makes them the ideal choice for both low pressure calibration and test applications.
