87240, DC/DC Displacement Sensor

Displacement sensors of series 87240 convert a displacement into an analog electrical signal. They consist of a differential transformer with moveable core, an oscillator and a demodulator. These components are integrated and encapsulated in a cylindrical housing made of stainless steel. The sensors are energized by DC voltage, which is converted to AC by the oscillator and brought to the primary
coil of differential transformer. The voltages induced by the two secondary windings of the transformer are demodulated, filtered and switched inverse to each other. The result is a 0 V signal, if the core is in the center position.

The direction of an axial core displacement is shown by the polarity of the output voltage. The amplitude of the voltage changes proportional to the magnitude of the core's displacement and respectively to the measured deflection.

In and output terminals of the displacement sensor are galvanically insulated and there is no connection to the housing of the sensor.

The mounting of the DC/DC displacement sensor will be done e.g. by a clip enclosing the sensor's housing. The dynamic unit to be measured should be connected to the
core of the sensor. To avoid an influence to the magnetic field and the measured value, coupling elements have to consist of a non magnetizable material like brass, aluminium or non-magnetizable steel.