News

Your current location: Home > News > Blogs

The working principle of differential pressure transmitter

December 20, 2019

With the development of differential pressure transmitter, selecting the best difference pressure transmitter will become more and more important. In general, we will depend on sensor's brand , measuring media or environment to buy, but I think don't let it be the driving factor motivating you to buy from someone. Only by understanding the working principle of differential pressure sensor, you'll purchase the suitable differential pressure transmitter.

How the differential pressure transmitter works?

Differential pressure transmitter design works on the principle of differential capacitance. In this design, the sensing element is a taut metal diaphragm located equidistant between two stationary metal surfaces, comprising three plates for a complementary pair of capacitors. An electrically insulating fill fluid (usually a liquid silicone compound) transfers motion from the isolating diaphragms to the sensing diaphragm, and also doubles as an effective dielectric for the two capacitors. Any difference of pressure across the cell causes the diaphragm to flex in the direction of least pressure. The sensing diaphragm is a precision-manufactured spring element, meaning that its displacement is a predictable function of applied force. So the diaphragm’s secondary function as one plate of two capacitors provides a convenient method for measuring displacement. Since capacitance between conductors is inversely proportional to the distance separating them, capacitance on the low-pressure side will increase while capacitance on the high-pressure side will decrease.

Above all, I recommend that try the compact type Differential Pressure Transmitter from Holykell, because it can measure the differential pressure of liquids or gases ,wide range of general purpose and industrial applications, it offers excellent linearity and performance over temperature,long, reliable service life with excellent long term stability. Customers can choose from multiple accuracy, outputs, pressure ports, electrical terminations and pressure ranges.

Ask an Expert