Pressure Sensors
Whether it’s controlling the flow of fluids, regulating hydraulic systems, or protecting sensitive equipment, pressure sensors act as links between physical processes and digital control systems. They detect the force exerted by gases or liquids and convert that into an electrical signal that automation systems can read and act on.
They provide real-time monitoring, enabling adjustments, and triggering safety protocols when needed. Without pressure sensors, automated systems would operate blindly, putting efficiency and safety at risk.
Main Types of Pressure Sensors
Strain Gauge (Piezoresistive)
- Uses a diaphragm with bonded strain gauges that flex under pressure.
- As the diaphragm bends, resistance changes are measured and converted to pressure readings.
- Applications: heavy machinery, oil and gas pipelines, automotive manufacturing.
Capacitive Pressure Sensors
- Work by measuring changes in capacitance as pressure moves a flexible diaphragm.
- Highly sensitive and power-efficient, ideal for precision monitoring.
- Applications: battery-powered devices, laboratory instruments, low-energy systems.
Piezoelectric Sensors
- Generate a voltage when a piezoelectric material is compressed by pressure.
- Excellent for fast, transient pressure changes, though less suited for steady-state measurements.
- Applications: hydraulic systems, pumps, compressors, robotic tooling.
Optical & Resonant Sensors
- Use advanced optics or resonating structures to measure pressure with unmatched precision.
- Provide long-term stability with little to no signal drift.
- Applications: aerospace, pharmaceuticals, research labs.
Common Applications
Pressure sensors show up across nearly every major industry, often serving as the difference between smooth operation and costly downtime:
- Hydraulics & Pumps – Maintain safe operation of presses, pumps, and compressors.
- Water/Wastewater – Monitor tank levels, flow rates, and pipe pressures, reducing manual checks.
- Pharmaceuticals & Clean Rooms – Maintain differential pressure to prevent contamination and meet strict regulations.
- Robotics & Pneumatics – Ensure consistent air pressure for precise motion in robotic arms and conveyors.
Pressure sensors are far more than measuring devices, they’re the backbone of safety, efficiency, and control in industrial automation. From rugged strain gauge models in heavy machinery to high-precision optical sensors in aerospace, each type fills a critical role in keeping processes stable and reliable.
Understanding which sensor to use helps users design smarter systems, troubleshoot faster, and protect valuable equipment.
Transcript From Video:
[0m:00s] Hey, I’m Mitchell. Welcome to another video in the RSP Education Series. Whether it’s controlling the flow of fluids, regulating hydraulic systems, or protecting sensitive equipment, pressure sensors act as the vital connection between physical processes and digital control systems. In this video, we’re going to walk through exactly what pressure sensors do, the different types used in industrial environments, how they operate behind the scenes, and where they’re most commonly applied. By the end, you’ll have a solid understanding of why pressure sensors are essential components across every major automated industry. If you like this kind of content and want more educational videos, please like and subscribe. This video is for educational purposes only. Consult a professional for your application. RSP Supply is not liable for any misuse of this information. With that said, let’s get right into it. In industrial automation, pressure sensors detect the force exerted by gases or liquids and convert it into an electrical signal that automation systems can easily process. Whether it’s controlling flow rates, managing hydraulic systems, or ensuring equipment safety, pressure sensors are the link between physical processes and digital control. Think of them as the eyes and ears of your system, constantly monitoring fluid dynamics, enabling real-time adjustments, and triggering safety protocols when needed.
[1m:33s] There are several types of pressure sensors. The first is the strain gauge, also known as piezoresistive. This type uses a diaphragm with bonded strain gauges. As pressure bends the diaphragm, the strain gauge resistance changes, creating an electrical signal that control systems process for real-time adjustments. Strain gauge sensors are commonly used in heavy machinery, oil and gas pipelines, and automotive manufacturing.
[2m:00s] Next is the capacitive pressure sensor. These measure changes in capacitance as pressure moves a diaphragm. They are highly sensitive and used in battery-operated or precision applications where both accuracy and power efficiency are critical. Then there are piezoelectric sensors. These generate a voltage when exposed to pressure, making them ideal for capturing fast-changing pressures in dynamic environments such as vibration monitoring or robotic tooling feedback.
[2m:45s] Optical and resonant pressure sensors are typically used in high-end applications like aerospace, medical automation, and research labs. These offer unmatched precision and long-term stability, making them ideal for processes that need to detect very small pressure changes over long periods. Here’s how these different sensors work. With strain gauge sensors, pressure flexes the diaphragm, stretching or compressing the strain gauges. This changes their resistance, which is measured by the electronics and translated into a pressure reading. Capacitive sensors work when pressure moves a flexible diaphragm closer to a fixed plate, changing the capacitance, which is measured by sensitive circuits. Piezoelectric sensors create voltage when squeezed by pressure, but because the signal fades quickly, they are best for monitoring short-term or transient pressure events.
[3m:43s] Pressure sensors are used across industries. In hydraulic systems, pumps, and compressors, they maintain safe operation and detect faults early. In water and wastewater treatment, sensors monitor tank levels, flow rates, and pipe pressures to automate treatment processes and improve efficiency. In cleanrooms and pharmaceutical manufacturing, pressure sensors maintain differential pressures to prevent contamination and ensure compliance. In pneumatics and robotics, precise air pressure control ensures smooth and consistent motion for robotic arms, conveyors, and other automated systems.
[4m:37s] Pressure sensors are more than measuring devices. They are critical to driving safety, efficiency, and control in industrial automation. We’ve covered how they detect and convert pressure into usable data, explored the main types—strain gauge, capacitive, piezoelectric, and optical and shown how they support a wide range of applications from hydraulics to robotics. A strong understanding of pressure sensors means better system design, smarter troubleshooting, and more reliable automation. For a full line of sensors and hundreds of thousands of other industrial automation products, visit rspsupply.com, the internet’s top source for industrial hardware