You probably have come across a pressure transducer. A pressure transducer is generally used to convert pressure into an analogue electrical signal.
Pressure transducers are available in many different types and each model performs a distinct function.
A strain gauge is the most basic type of pressure transducer. Pressure is converted into an electrical signal by the physical movement of the gauge. These gauges are fitted in the diaphragm of the pressure transducer. It is then wired in a Wheatstone Bridge configuration. The pressure applied to the pressure transducer causes a deflection in the diaphragm.
The change in diaphragm position produces a change in electrical resistance which is proportional to the pressure implied. Pressure transducers are usually available with three different types of electrical output.
Millivolt output pressure transducers
Millivolt output pressure transducers are one of the most economical and affordable types of pressure transducers. Generally, the output of millivolt transducers is around 30mV. The output is directly proportional to the pressure transducer’s input. This input is described as excitation and any fluctuation in excitation causes the electrical output to fluctuate as well. These transducers should not be placed in an electrically noisy environment.
Voltage output pressure transducers
These transducers incorporate internal signal conditioning. Therefore, they provide a higher output compared to millivolt transducers. The general output is around 0-5Vdc or 0-10Vdc. These transducers are not susceptible to an electrically noisy environment due to the higher level of output.