Air Pressure Sensing and Gas Pressure Regulation

Q-S181 Absolute Pressure Sensor, a stand-alone sensor for measuring atmospheric air pressure. For data acquisition and display, consider the Q-C610 LabQuest Mini data acquisition interface and Q-C901 LoggerPro software. However, the output can be recorded with any other interface with 0-5 V analogue input. Applications include environmental monitoring as well as pressure correction of gas efflux measurements.

Q-G261 Pressure Regulator and Gauge, maintaining accurate control of gas pressure. Designed for low volume and low pressure, this regulator ensures that the flow rates set in a gas exchange system remain consistent throughout the experiment. By establishing and maintaining a constant system pressure, it ensures a steady supply of gas to all chambers at a specified flow rate. With a range of 0-103.4 kPa (0-15 psi), the Q-G261 Precision Regulator can be used downstream of high volume gas pumps or to regulate pressure from a compressed gas source.

Q-G262 Gas Blow Off Valve, used to maintain a constant back pressure in a gas supply system, such as a gas mixing system. The blow-off gas pressure is configured to exceed the level set by the pressure regulator, resulting in the continuous release of a small amount of gas. This controlled venting ensures that the flow rate from the gas mixing system remains slightly higher than the total common manifold flow rate, thus maintaining the settings of the Q-G262 Valve. When attempting to maintain a constant flow rate across multiple units connected through a common manifold using needle valves or rotameters, a constant pressure at the manifold is essential. The Q-G262 Blow Off Valve is used to maintain this constant pressure. Its implementation ensures that changes in flow rate at one rotameter will not affect the flow rates of the others, providing a reliable and independent control mechanism.