What they look like

This sensor measures the total pressure on a system. When the port is left open, the sensor measures the atmospheric pressure. However when the sensor is connected to a sealed system, it adds the system’s pressure effect (negative or positive) to the atmospheric value.

How the sensor works

It contains a membrane which flexes as pressure changes. This sensor is arranged to measure absolute pressure. One side of the membrane is a vacuum, while the other side is open to the atmosphere. The sensor produces an output voltage which varies in a linear way with absolute pressure. It includes special circuitry to minimize errors caused by changes in temperature. Be aware of the upper limit of readings possible from the sensor you are using.

Where it can be used

• Investigate the relationship between pressure and volume - Boyle’s Law.
• Measure vapor pressure of liquids.
• Study the effect of temperature on gas pressure, Gay-Lussac’s law.
• Monitor the production of O2 during photosynthesis of an aquatic plant in a closed system.
• Determine the rate of transpiration for a plant under different conditions.
• Determine the rate of respiration in germinating pea or bean seeds.
• Study the effect of temperature and concentration on the rate of decomposition of hydrogen peroxide.
• Atmospheric pressure measurements.
• Variation of pressure with height above sea-level- an altimeter.
• Variation of pressure with depth and density in a liquid.