Compare our sensors
Not sure which sensor is the right fit? Select up to three sensors to view technical comparison.
Rotating Torque Sensors
Rotating torque sensors (also known as rotational torque or torsion sensors) are used for —precise measurement of torque directly on rotating shafts and components - such as in drivetrains, motor and gearbox test benches, or in production and quality assurance processes. They provide reliable measurement data when torque needs to be captured under real operating conditions, from static loads to dynamic load changes.
At Althen, you will find rotating torque sensors in various designs and with different measurement principles, tailored to your mechanical installation and measurement concept. This enables reliable implementation of measurement tasks in mechanical engineering, automotive development, e-mobility, as well as in test benches and end-of-line testing.
The Right Rotating Torque Sensor for Your Application
Rotating solutions are typically chosen when:
- Torque must be measured under rotation (realistic measurement on rotating systems)
- High dynamics are required (load changes, acceleration/braking processes, transient operation)
- A robust and integrable measurement system is needed (suitable mechanics, signal conditioning, optional interfaces)
Depending on your application, we also support you in selecting the appropriate measurement chain (e.g., signal transmission, amplification, data acquisition), ensuring that your measurement results are not only accurate but also stable and reproducible within the overall system.
-
Measurement under real operating conditionsTorque is measured directly within the drivetrain – including speed, acceleration/braking and real-world load profiles. This makes the results more representative of real-world conditions than indirect estimates or measurements taken ‘at the housing’.
-
High dynamic response and accuracy during load changesRotary sensors are particularly well suited to transient processes (e.g. torque peaks, ripple, starting torques, control processes). This makes them ideal for test benches, NVH/powertrain analyses and efficiency tests.
-
Integration & process reliability: compact, robust, reproducibleAs integrated components, they provide stable, repeatable measurement values and can be seamlessly integrated into test and automation environments. This reduces measurement uncertainty, simplifies comparability and supports quality assurance.
What to Consider When Selecting a Rotating Torque Sensor
For reliable system design, the following factors are typically crucial:
- Measurement range / nominal torque
Including overload capacity and appropriate safety margins. - Speed range and dynamic behavior
Consider the required performance under dynamic loads such as acceleration, braking, and load changes. - Mechanical integration
Shaft connections, flanges, and available installation space must match the application. - Environmental conditions
Factors such as temperature, dust, humidity, and possible shock or vibration loads should be taken into account. - Output signal & interfaces
Analog or digital outputs must be compatible with your test bench, PLC, or data acquisition system. - Calibration & traceability
Important for quality assurance, compliance with standards, and audit requirements.
Typical Applications of Rotating Torque Sensors
The main applications for rotating torque sensors are found wherever torque needs to be measured directly on a rotating shaft under real load conditions:
- Test benches for engines, gearboxes & drivetrains
Development, validation, efficiency testing, and endurance testing - E-mobility / electric drives
Electric motors, inverter setups, eAxles, energy recuperation, torque ripple analysis - Quality assurance & end-of-line (EOL) testing
Functional testing, friction torque and breakaway torque measurement, comparison with reference values - Mechanical engineering & production systems
Drive monitoring, process stability, wear and condition monitoring - Tool and spindle testing (e.g., screwdriving systems, milling/drilling spindles)
Torque progression, control quality, overload peaks - Pumps, compressors, and fans
Power consumption, efficiency, and performance curve measurements - Wind energy & rotor systems
Torque and power analysis in drivetrains (test bench and field testing) - Robotics & automation
Drive and axis characterization, control system testing, load profiling - Research & university laboratories
Model validation, tribology/friction torque analysis, material and component testing
Our Services
Applications using rotary torque sensors
Our Projects
Frequently asked questions about Rotating torque sensors
Answers to the most important technical Questions
What measuring ranges are available for rotary torque sensors?
Depending on the design, rotary torque sensors are available for measuring ranges from low torque values up to high industrial and test-bench loads. The SGR510, SGR511 and SGR512 series cover torque ranges up to 13,000 Nm. This makes rotary torque sensors suitable for applications such as engine and gearbox test benches, drivetrains, end-of-line testing, production monitoring, e-mobility, pumps, compressors, wind energy and robotics. Depending on the version, rotational speed, angle and power can also be measured or calculated in addition to torque. The appropriate measuring range should always be selected with sufficient reserve relative to the maximum expected load. In addition to the rated torque, rotational speed, load cycles, dynamics, overload reserve, mechanical connection, output signal, interfaces and calibration should also be considered. Althen can help select the appropriate rotary torque sensor and complete measurement chain.
How do rotary torque sensors work?
Rotary torque sensors measure torque directly on a rotating shaft or component. The torsional deformation of the sensing element caused by the applied torque is detected and converted into an electrical signal. This allows the actual torque to be measured during operation, for example in drivetrains, engine and gearbox test benches, production systems or end-of-line tests. In the SGR torque sensors offered by Althen, measurement is based on strain gauges. A full-bridge circuit detects the torsion of the shaft and helps reduce the influence of off-centre forces. The measured values are acquired in the rotating section of the sensor and then transmitted contactlessly to the stationary section. This eliminates the need for slip rings, which can be subject to wear or introduce signal interference. Depending on the version, rotational speed, angle and power can also be measured or calculated in addition to torque. The signals are then available as analogue or digital outputs for test benches, control systems, data acquisition or process monitoring. Important factors for reliable measurement include the appropriate measuring range, maximum rotational speed, behaviour under dynamic load changes, mechanical connection via shafts or flanges, environmental conditions, output signal, interfaces and calibration. Althen can help select the appropriate rotary torque sensor and complete measurement chain, including the sensor, signal transmission, amplification, data acquisition and calibration.
How is data transmitted in rotary torque sensors?
Rotary torque sensors transmit measurement data either contactlessly via telemetry or through slip rings. Contactless systems require less maintenance and generally offer a longer service life, especially at high rotational speeds. Some models feature integrated signal transmission using inductive or optical methods.