Differential Pressure Sensor

Description

A Differential Pressure Sensor

The differential pressure sensor is a specific type of pressure sensor that measures the pressure changes or “DP” between two points. It differs from a static or absolute pressure sensor, which measures the pressure at a single point only.
A barometer or altimeter is an example of an absolute pressure sensor, while an air sensor is an example of a differential pressure measurement device.
“DP” is also used for flow measurement equipment. For this reason, it is employed in many systems as a device for measuring flow.
Differential pressure measurement equipment is used to measure low-pressure ranges in medical, industrial systems, etc.
DP measurement devices typically measure pressure in units of inches or Pascal columns of water or millibar.

۱ Pascal (Pa) = 0.00402 inH20

Unlike absolute or gauge pressure sensors, the differential pressure transmitter does not have a fixed reference in measurement. A significant increase in pressure difference could result from either an increase or decrease in pressure at one of the two measuring points.
Differential pressure measurement equipment is primarily used in industrial and domestic applications. Pressure difference often forms the basis for other measurements such as flow, level, density, viscosity, and even temperature, with level and flow being the most common.
The differential pressure transmitter has two inputs (as shown in the diagram below). The pressure-measuring sensor in this transmitter is located at the bottom of the device. One of the transmitter’s inputs is for connection to high pressure, and the other is for connection to the lower pressure input.

Exploring the Applications of Differential Pressure Sensors

‌Differential pressure sensors typically have a very high accuracy (more precise than 1.0 Pascal). Below, we’ll examine a few systems that utilize differential pressure sensors.
The Continuous Positive Airway Pressure (CPAP) device, used for the definitive treatment of sleep apnea, requires a sensor to regulate the user’s airflow.
Industrial applications such as room pressure control and regulation require precise identification of small pressure changes, for example, for the measurement of natural gas in residential and commercial systems.
They are also used for measuring air quality and airflow with high precision through the use of differential sensors.