Magnetic strain sensors hold on ferromagnetic components by themselves and press a foil strain gauge so firmly against the surface that friction takes over the job of the adhesive. They read the surface strain with the same quality as a bonded gauge – after seconds instead of three quarters of an hour, and without drilling, grinding or gluing.
When a magnet sensor is worth it
The component is left as it is. No adhesive, no screws, no drilling.
Reusable. The sensor comes off as easily as it went on and is set at the next measuring point.
Cannot be overloaded. Instead of damage, an offset occurs.
For steel structures – for checking FEM calculations and for stress analysis.
The designs compared
Strain sensor DKFD – holds by its own magnet, steel housing Ø 34 mm, protection IP54, range ± 300 … ± 500 µε depending on the surface. Reads through coats of paint.
Magnetic holder DKFA – two springs and two knurled screws press a StrainPad (Ø 10 mm, 0.2 mm high) on with 100 … 300 N, maximum strain ± 800 µm/m.
What you need with them
Both sensors are passive and work with 350 Ω foil strain gauges and gauge factor 2.0 – so on any strain gauge amplifier. Suitable units are listed under strain gauge bridge amplifiers.
