Pressure sensor for water and air
Depending on the medium, a pressure sensor has different requirements. For water, a good seal is essential, while air applications focus on fast and accurate measurements. The table below compares the key characteristics side by side:
| Application |
Characteristics |
Recommended configuration |
| Water |
Waterproof housing (IP65/IP67), resistant to moisture and contamination |
Ceramic or silicon cell sensor |
| Air |
Fast and stable signal transmission, suitable for compressed-air and vacuum applications |
Silicon cell sensor, compact housing |
If you only need simple visual pressure reading, see our pressure gauges for analogue measurements. For advanced signalling and integration with your control system, choose a pressure transmitter.
Types of pressure sensors
- Gauge (relative) pressure sensor – measures overpressure relative to atmospheric pressure.
- Absolute pressure sensor – measures pressure relative to a vacuum reference.
- Differential pressure sensor – measures the pressure difference between two points.
- Vacuum pressure sensor – detects pressures below atmospheric pressure.
Festo pressure sensors
As experts in pneumatics, we offer a complete range of Festo pressure sensors with measuring ranges from 0–0.05 bar to 0–10 bar, accuracy up to 0.05 %, and interfaces such as CANopen and IO-Link.
Applications of pressure sensors
Pressure sensors are used across many sectors, each with its own purpose:
- Process industry (chemicals, pharma, food & beverage) – monitoring pressure in pipelines and reactors to ensure product quality and safety.
- Water and wastewater management – measuring water pressure in pumping systems and pipelines, preventing pipe bursts and controlling filtration processes.
- HVAC and refrigeration – regulating refrigerant pressure and airflow for stable climate control and energy-efficient operation.
- Medical gases and laboratories – accurately monitoring pressure of oxygen, nitrogen or vacuum to ensure patient safety and reliable test results.
- Machine safety and hydraulics – protecting hydraulic systems against overpressure and ensuring stable machine operation.
Frequently asked questions about pressure sensors
What is a pressure sensor?
A pressure sensor is a measurement device that converts the pressure of gases or liquids into an electrical signal. This allows your control system to continuously monitor pressure and intervene for a stable, safe process. The sensor helps prevent faults and overpressure and enables accurate control. Depending on the application, there are versions for a wide range of pressure ranges and process conditions.
How does a pressure sensor work?
A diaphragm or sensing cell deflects under pressure; this deflection is measured using, for example, a piezoresistive bridge, a capacitive element or an inductive system. The electronics linearise, apply temperature compensation and convert the signal to 4–20 mA, 0–10 V or a digital protocol (HART, IO-Link). Your PLC or controller reads this signal for monitoring and control. The result is a stable, repeatable measurement, even when process conditions fluctuate.
What does a pressure sensor measure?
Pressure sensors measure gauge (relative) pressure, absolute pressure, vacuum pressure or the pressure difference between two points. The type you need depends on reference and process: absolute pressure for vacuum or leak tests, gauge pressure for line pressure and differential pressure for flow or filter monitoring. Typical ranges span from millibar to hundreds of bar. With suitable sensors, fast pressure transients or pulsations can also be recorded.
How does a differential pressure sensor work?
A differential pressure sensor has two ports and determines the difference between the high- and low-pressure sides. This is often across an element such as a filter, orifice or heat exchanger, where the pressure loss indicates flow or fouling. Inside the sensor, the difference is measured mechanically on a diaphragm or via two sensing cells and converted electrically. The output signal is directly proportional to ?p.
When should I choose a digital pressure sensor?
Choose a digital pressure sensor when you need accurate logging, parameterisation and communication via fieldbuses (e.g., IO-Link or HART). Digital models often provide local displays, switch outputs and diagnostics, useful for commissioning and maintenance. They are less sensitive to noise and long cable runs than analogue signals. They are also ideal for remote monitoring or integration with MES/SCADA.
Choose the right pressure sensor
Our instrumentation specialists analyse your medium, pressure range and interface requirements. Customers who involve us early experience fewer failures and optimal process control. Book your free consultation today!
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