Variable Capacitance Pressure Sensor

A pressure sensor is a device for pressure measurement of gases or liquids pressure is an expression of the force required to stop a fluid from expanding and is usually stated in terms of force per unit area.

Variable capacitance pressure sensor.

In the typical capacitor the distance between the two plates is fixed but in variable capacitance transducers the distance between the two plates. Which converts applied pressure into a current signal like 4 20ma. Output current of 4 to 20 ma. The capacitive transducer comprises of two parallel metal plates that are separated by the material such as air which is called as the dielectric material.

Capacitive pressure sensor having a substrate with a curved mesa us5792957a en 1993 07 24. A variable capacitance sensor is constructed with its capacitance plates connected at their center. An easy way of measuring the change in capacitance is to make it part of a tuned circuit typically consisting of the capacitive sensor plus an inductor. What is the capacitive pressure transducer.

The advantages of this technology are obvious in measurement sensitivity at low pressure ranges. Endress hauser gmbh co. Viatran differential pressure transmitters make use of variable capacitance technology as do the viatran gage type and absolute pressure sensors. Stress relieving means are provided to eliminate hysteresis effects from the connecting structure.

Typical variable capacitance sensor cross section. This is shown in figure where the movement of a. A pressure sensor usually acts as a transducer. It is a passive transducer that means it requires external power for operation.

An example of a capacitive pressure sensor is shown to the right. The conducting surfaces forming the capacitor are insulated from the central connection and each other. The capacitive transducer is used for measuring the displacement pressure and other physical quantities. The capacitance of the capacitive transducer changes because of many reasons like overlapping of.

This imbalance is detected in a capacitance bridge circuit and converted to a d c. Typically one electrode is a pressure sensitive diaphragm and the other is fixed. The capacitance pressure transmitter is a pressure measurement device. Capacitive pressure sensors with high linearity by optimizing electrode boundaries us6056079a en 1996 12 19.

It generates a signal as a function of the pressure imposed. For the purposes of this article such a signal is electrical. The structure provides decreased thermal path lengths to reduce thermal effects. A pressure transducer is a device that measures the pressure of a fluid indicating the force the fluid is exerting on surfaces in contact with it.

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