摘要 |
<p>A compact, portable and NIST traceable differential pressure source (22) that dynamically generates very low pressures includes at least one adjustable valve (30) in-line with a fluid, such as air, flowing through the valve (30). A differential pressure is created across a pressure control device (34) downstream from the valve (30). The differential pressure varies depending on the volume of the gas flow and the amount of resistance to the gas flow. The pressure generating device (22) utilizes a miniature pump (24) to create a pressure, or, alternatively, a vacuum, that causes gas flow. The pressure generating device (22) is compact and capable of providing a very low and stable differential pressure by using a dynamic flow that compensates for temperature changes and volume changes. The compact module (22) may be configured as a plug-in module for existing handheld calibrators (12) for operator ease of use.</p> |