Unlike regular pressure sensors that focus on absolute or gauge pressure differential pressure sensors concentrate on the difference between two points. They can be used to monitor pressure levels in sealed tanks, cleanliness of filters or flow across an orifice. Differential pressure transmitters are available in a variety of sizes from rugged industrial packages to miniature OEM designs. They are also available in explosion-proof configurations for hazardous locations.
How to Select a Differential Pressure Sensor
One important selection criterion is the maximum line pressure that a differential pressure sensor can be subjected to without overpressure. The maximum line pressure is typically quoted on the product data sheet. Another important consideration is the maximum pressure change between high and low sides of a differential pressure sensor. This change in pressure is determined by the length, inside diameter and surface smoothness of the connecting pipes between the sensor and point of measurement.
The most common type of differential pressure sensor is a diaphragm-based sensor that relies on the deflection of a sensing diaphragm when subjected to two different pressures. These sensors can be configured as unidirectional or bidirectional. They are also available in a wide variety of mounting options such as threaded sensors for a hose or flange installation, flush mount to avoid clogging with debris and miniature versions to be soldered onto circuit boards.
For a higher level of sophistication, some sensors offer continuous wireless monitoring with alerts via WiFi or cellular connectivity. Some even have an OTA firmware update capability so that they can automatically receive updates to their software. This makes it easier to scale a device and to install a new sensor or replace a damaged one without disrupting other devices or interrupting production.