​New flexible torque sensor

Jon Lawson

HBM Test and Measurement has introduced its new T21WN torque transducer. Based on strain gauge technology, it uses contactless energy and measurement signal transmission to measure torque. The torque transducer enables demanding static and dynamic measurements of torque, rotational speed and angle of rotation to be performed on non-rotating as well as rotating components. It is for laboratory, test shop and testing applications as well as for use in production and process monitoring and quality assurance.

Apart from the torque output signal of +/-10 V at nominal (rated) torque, it also provides a standard frequency output signal of 10 kHz+/- 5 kHz.


The T21WN torque transducer is available with nominal (rated) torques ranging between 0.1 Nm and 200 Nm. The maximum permissible rotational speed of torque measuring system is up to 20,000rpm, depending on the measurement range. An integrated rotational speed/angle of rotation measuring system with 360 pulses per revolution completes the transducer and can be used up to the specified maximum nominal (rated) rotational speed without restrictions.


The transducer is supplied with the direct voltage of 24V as that is common in test benches. The T21WN is suitable for use in substantially more dynamic applications than the preceding model, the T20WN, thanks to its measurement bandwidth of 1 kHz.