2024-03-08
welding rod-Pressure Sensors: The Design Engineer's Guide
When a force is applied to a piezoelectric material, an electric charge is generated across the faces of the crystal. This can be measured as a voltage proportional to the pressure (see diagram to the right).There is also an inverse piezoelectric effect where applying a voltage to the material will cause it to change shape.A given static force results in a corresponding charge across the sensor. However, this will leak away over time due to imperfect insulation, the internal sensor resistance, the attached electronics, etc.As a result, piezoelectric sensors are not normally suitable for measuring static pressure. The output signal will gradually drop to zero, even in the presence of constant pressure. They are, however, sensitive to dynamic changes in pressure across a wide range of frequencies and pressures.This dynamic sensitivity means they are good at measuring small changes in pressure, even in a very high-pressure environment.