High-precision linear position sensors for accurate displacement measurement
Linear position sensors are designed to measure the distance between an object and a reference point, as well as detect precise changes in position. They work by converting mechanical displacement into an electrical output signal that can be processed and analyzed.
A variety of measurement principles—such as inductive, magnetostrictive, or potentiometric technologies—can be used to ensure accurate and reliable results across a wide range of applications.
Linear position sensors and measurement systems are widely used in both industrial environments and scientific laboratories. They are available in various designs, configurations, and interface options, allowing seamless integration into diverse systems and applications with different technical requirements.
Discover our range of linear position sensors
We offer standard linear position sensors but can also help you with a customized design or a complete measurement solution.
Linear position sensors are devices that measure the displacement or position of an object in a straight line. These sensors convert mechanical motion into an electrical signal, allowing for precise monitoring and control in a wide array of industrial processes. They find applications in sectors such as automotive, aerospace, manufacturing, and robotics.
We offer linear position measurement technology for a wide range of applications that require accurate travel, distance, or position monitoring. Our portfolio includes both standard and specialised sensor solutions, making it easy to select the right sensor for your application.
Althen linear position sensors are based on different physical measurement principles. This allows us to offer the ideal solution for your installation and performance requirements.
Our sensor range can be divided into:
We also supply intrinsically safe EX position sensors for hazardous areas, including:
These sensors are available in various configurations to match your industry requirements.
Machine equipment often requires sensors that are reliable, durable, and accurate. Our linear and rotary sensors are designed for heavy duty environments and help reduce maintenance costs. They can also support your automation and digitalisation programmes.
Whether you work with small-scale production or high-volume manufacturing, reliable equipment is key to maintaining consistent quality. Our sensors help you measure with confidence, every day.
Choosing between contacting and non-contacting linear position sensors depends on the specific requirements of the application, including factors such as precision, environmental conditions, and the durability needed for long-term use. Contacting sensors are often used in applications where cost is a critical factor, and physical contact is permissible, while non-contacting sensors are preferred for high-precision applications and environments where wear and tear need to be minimized.
They usually involve a direct mechanical connection between the sensor and the moving part. Potentiometric sensors are a common type of contacting linear position sensor. They use a resistive element and a wiper that makes physical contact with the surface. As the object moves, the wiper slides along the resistive element, creating a variable voltage output.
Not ideal for applications where non-contact measurement is essential.
Linear variable differential transformers (LVDT sensors)
Within their specified measurement range, LVDT sensors provide excellent linearity. They are capable of detecting very small changes in position and have virtually unlimited resolution. As a result, LVDT sensors are also suitable for measuring high accelerations and high measurement cycles.
Linear inductive position sensors
Linear inductive position sensors are durable, long-lived, and especially stable under temperature fluctuations. That means they are ideal for measuring linear travel in almost any industrial setting – especially with hydraulic or pneumatic applications.
Draw-wire sensors
Draw-wire sensors (also called string pot displacement sensors) can measure distances at up to 0.01 mm accuracy. They measure the position and movement of an object by means of a flexible steel cable that is fed from a spring-loaded spool. The linear movement at the end of the cable is thus transformed into a rotational movement.
Linear potentiometers
Linear-motion potentiometers (potentiometric sensors and displacement sensors) are based on electrical resistance. Their resistance can be altered mechanically (by rotation or transposition). These sensors are primarily used as continuously adjustable voltage dividers. Althen linear potentiometers are highly compact and lightweight, and they come in various configurations.
Hall effect sensors
Sensors based on the Hall effect are used to measure the strength of magnetic fields. Their primary applications are in longevity and stress testing as well as for measuring magnetic fields or the thickness of layers. Our Hall sensors are also available in several modified versions for special requirements.
As technology continues to advance, the demand for accurate and reliable linear position sensors will keep growing. Althen Sensors & Controls supports this development with sensor solutions designed for precision, efficiency, and long-term reliability. From automotive and manufacturing to aerospace applications, linear position sensors play an important role in the ongoing evolution of industrial automation and control systems.
Machine equipment requires heavy-duty sensors. The sensors must be reliable, durable and precise. Our linear and rotary sensors help you save (maintenance) costs and can be part of your automation and digitalisation programme. Regardless of whether it is a small batch or mass production, manufacturing quality products requires quality equipment. Our sensors are designed for high performance applications and offer you long life, exceptional repeatability, high straightness and customised lengths for various applications. Looking for a contactless solution for accurate position measurement?
Contact us today and discover the difference in accuracy, reliability, and innovation.
Answers to the most important technical Questions
Displacement sensors and transducers are available in different measuring ranges, depending on the measurement principle and product series. Althen offers solutions for measuring very small linear movements in the millimeter range as well as longer distances of several meters.
For short, precise measurements, suitable options include LVDT displacement transducers, inductive displacement sensors, Hall sensors and linear potentiometers. Draw-wire sensors and magnetostrictive position sensors are often used for larger strokes and longer linear movements.
Althen's draw-wire sensors offer measuring lengths of up to 50 m, while other displacement sensors cover ranges from a few millimeters to several hundred millimeters or more, depending on their design.
The appropriate measuring range depends on the application, available installation space, accuracy requirements, environmental conditions and required output signal.
The resolution of displacement sensors and transducers depends on the measurement principle, measuring range, output signal and signal processing electronics.
LVDT displacement transducers can detect extremely small changes in position and offer virtually infinite resolution. Depending on their design, Althen's linear incremental encoders achieve resolutions down to 2.5 µm.
Draw-wire sensors are available with measuring ranges of up to 50,000 mm, with Althen specifying an accuracy of up to 0.01 mm.
Other technologies, including inductive, magnetostrictive, Hall-effect, eddy-current and potentiometric displacement sensors, offer different resolutions depending on the product series. They are suitable for applications with varying requirements for precision, robustness and measuring range.
When selecting a displacement sensor, resolution and accuracy should always be considered together. Other important factors include measuring range, repeatability, linearity, signal processing, installation requirements and environmental conditions.
The operating temperature range of displacement sensors and transducers depends on the measurement principle and product series. Many industrial models are designed for harsh environments, offering high temperature resistance, robust housings, protection ratings up to IP69K and resistance to environmental influences.
The specific operating temperature range should always be verified in the sensor's datasheet. For example, PR-series LVDT displacement transducers are designed to operate at temperatures from -40 °C to +125 °C, with higher temperature options available.
Inductive displacement transducers offer particularly stable performance across temperature variations, while magnetostrictive position sensors are largely unaffected by temperature, shock, vibration and contamination.
When selecting a sensor, it is important to consider not only the ambient temperature but also temperature fluctuations, installation conditions, protection rating, humidity, vibration and the required measurement accuracy.
We will be happy to help you select the right displacement sensor or transducer for your application.
The way displacement sensors and transducers are connected and their signals processed depends on the measurement principle and output signal.
Many sensors provide an analog output, such as resistance, 0–10 V, 0.5–4.5 V or 4–20 mA. These signals can be processed by a control system, display, measuring amplifier or data acquisition system.
Other displacement sensors provide digital or incremental signals, such as pulses, SSI, CANopen or other interfaces. Incremental sensors detect changes in position and usually require referencing, while absolute sensors can provide position information directly after power-up.
For reliable signal processing, it is important to select the appropriate output signal and ensure the correct supply voltage, suitable signal conditioning, proper wiring and stable mechanical installation.
Displacement sensors and transducers should be recalibrated when consistently high measurement accuracy needs to be verified or when operating conditions may affect the measurement signal.
Common reasons for recalibration include routine quality checks or measuring equipment monitoring, intensive use, strong vibrations, temperature changes, mechanical loads, repairs or component replacement.
The appropriate calibration interval depends on the sensor type, application, required accuracy and internal quality specifications. In many industrial applications, an annual inspection is recommended. Shorter intervals may be appropriate for safety-critical test benches, intensive use or applications with tight tolerances.
The entire measurement chain should also be checked and, if necessary, recalibrated after a new installation, noticeable measurement deviations or changes to the mechanics, cables, signal conditioning or control system.
Further information on calibration is available on our website.
The service life of displacement sensors and transducers depends largely on the measurement principle, mechanical loads and environmental conditions. Althen offers robust displacement sensors with protection ratings up to IP69K, resistance to environmental influences and long service life.
Contactless sensors, such as LVDT, inductive, magnetostrictive, Hall-effect and eddy-current sensors, are generally particularly durable because they operate without mechanical sliding contact that is subject to wear. LVDT sensors are therefore well suited to continuous operation and demanding environments, while inductive displacement transducers also offer high wear resistance, robustness and durability.
For contact-based sensors, such as linear potentiometers, service life is usually specified in measurement cycles. For applications involving frequent movement, Althen offers models rated for more than 50 million measurement cycles, with some versions achieving up to 100 million cycles, including the LPC, SLPT and ELPH.
The actual service life in years depends on factors such as movement frequency, stroke, speed, lateral forces, temperature, humidity, vibration, protection rating and installation conditions.
We will be happy to help you select the right displacement sensor or transducer for your application. Contact us for advice.