Factors affecting the measurement accuracy of magneto-electric torque sensors

The measurement accuracy of magneto-electric torque sensors is constrained by multiple factors. Mastering the key influencing factors is the core to ensuring the measurement accuracy.

1. Performance of the sensor itself

The stability of the elastic modulus of the elastic shaft material and the machining accuracy directly determine the measurement basis. Uneven material or excessive surface roughness can lead to abnormal stress distribution, causing the linear relationship between torsion angle and torque to fail. Sensitivity drift and linearity deviation of the detection element (such as Hall element, induction gear) can also cause signal conversion distortion and affect measurement accuracy.

2. Installation process errors

Coaxiality out of tolerance during installation (larger than 0.05mm) causes the elastic shaft to bear additional bending moments, resulting in non-torque-related deformation. Improper bolt tightening torque, too tight will cause plastic deformation of the elastic shaft, too loose will cause vibration displacement, both interfere with the true measurement of the torsion angle.

3. Environmental interference factors

Temperature changes cause changes in the modulus of the elastic shaft material, resulting in measurement deviations of the torsion angle; The sensitivity temperature drift of the detection element also accumulates errors. Strong electromagnetic interference in industrial sites can easily couple into signal transmission lines, causing signal distortion if shielding and filtering measures are insufficient. The inertial force generated by the vibration of the equipment can interfere with the normal deformation of the elastic shaft. Long-term vibration may also cause loosening of components and wear of connections.

4. Lack of calibration and maintenance

Too long calibration cycles or the use of low-precision standard equipment cannot correct sensor performance drift. Failure to clean up impurities such as iron filings and oil stains on the sensor surface in a timely manner on a daily basis, or failure to check the preload of the installation bolts regularly, will gradually reduce the measurement accuracy.