The Way In Which Pressure Sensors Basically Work

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The Way In Which Pressure Sensors Basically Work

by Adriana Noton

Pressure sensors are devices that are meant for measuring the pressure. The measuring applies to any liquid or gas. When the level of substance has reached a certain limit and has even passed over it, the device translates the force generated into an electric signal. This signal is interpreted by a computer and in this way the measurement is made.

The force parameter is not the only one measured; there are also secondary measurements like the substance amount or the flow of the liquid/gas. These devices can measure a lot of things. The reading can be either static or dynamic.

During the steam age the first devices were made and they became very popular. Since then, the technology has evolved a lot, and they have adapted. Their popularity is still the same in our times. They can be split in three categories depending on how they work: variable capacitance, strain gage and piezoelectric.

The forms and design types of these<a href="http://www.disensors.com/products_sub.aspx?id=212">pressure sensor</a> devices can be very different. The classification is made depending on cost or performance, the measurement range or the temperature at which they are used. The dynamic sensors can indicate when the speed and pressure are modifying. They are known as high performance devices and they are usually piezoelectric.

The strain gage systems are made of two things: the strain gauge and the diaphragm. The diaphragm detects the changing in force when the level of the fluid grows. Then the strain gauge will oppose resistance for that force, and the resistance will be calculated by a DAQ module (Data Acquisition System).

When it comes to the devices that use variable capacitance, these are made of two metal plates. Actually it is one metal plate and a metal diaphragm. When the force changes, the distance between the plates changes as well and this indicates the difference in pressure. Like the <a href="http://www.disensors.com/products.aspx?id=16">accelerometer</a>, these devices are more stable than others but they do not function well in high temperature conditions. Also they are harder to assemble then the other types.

The piezoelectric devices are built from quartz crystals and they use the natural electric characteristics of these materials. When they are under physical stress, these crystals generate an electric shock. They require amplification of the signal. They are less resistant to physical shocks and high vibrations than the other devices.

In normal conditions, the signal generated through these methods is weak. It is measured in mV, which is a measure unit one thousand times smaller than the Volt. The Volt numbers obtained are related to the intensity of the force. This means that for 0 Volts, 0 Bars are corresponding as pressure measuring and in this case there is no generated signal. If the limit is five Volts, then the Pressure will be five Bars.

Nowadays pressure sensors have a very high range of use, they are commonly used in the food industry, for example. With no exceptions, they have the role of measuring the forces made by the fluids. They are also able to detect the flow and the fluid level.

Choose from a wide selection of state-of-the-art scientific technologies including the <a href="http://www.disensors.com/products.aspx?id=21">linear position sensor</a>, calibration systems, load cells, <a href="http://www.disensors.com">mass flow sensor</a>, and accelerometer. These specialized tools are very popular among the research and development industries.