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Functional Principle, Technical Data
induSENSOR, EDS
2.
Functional Principle, Technical Data
2.1
Measuring Principle
Eddy current long-stroke displacement sensors transform the linear motion (e.g. displacement of a piston in
hydraulic cylinders) into a linear electrical signal. The measuring object is an aluminum tube that is moved
concentrically and without contact over a coil. By inducing eddy currents in the aluminum tube, energy is
extracted from the coil, thus detuning it. The integrated electronics converts the tube position into a linear
electrical output signal. The eddy current principle applied works contact-free. The sensors are therefore not
subject to mechanical wear.
0
1/1
4
12
20
Sensor
housing
Sensor rod
Output signal (mA)
Measuring range
1/2
Measuring tube
Fig. 1 Output characteristic of an eddy current long-stroke displacement sensor. Position of measuring tube:
start of measuring range
