A traditional pressure regulator and needle valves work by filling and venting pressure of the system. This wastes a great deal of compressed gas and can introduce hysteresis error due to over-shoot and under-shoot of a test point. Because pressure regulators are designed to work with flowing gas or liquid, they work very poorly when there is no flow. A compressed gas control device such as the Ralston QTCM calibration manifold, QTVC volume controller or NPAK pressure source actually changes the volume of a closed system to control the pressure. This approach makes measurement more accurate and the calibration easier to perform. The pressure-balanced design of the QTVC and NPAK provides higher precision due to smoother operation and a larger piston diameter.
Ralston Instruments offers a wide range of digital pressure gauges for pressure calibration in the lab or in the field. From vacuum to 5000 psi, we offer an assortment of gauges for any application. Our pressure calibration kits combine a hand pump or pressure control device with the pressure gauge, hoses, adapters and gauge connections needed to perform any calibration. These complete kits include all the necessary equipment to get the job done.