Unformatted text preview: ply an output signal unless the input signal is above a
certain threshold. © Festo Didactic GmbH & Co. KG • FP 1110 159 11. Physical fundamentals With the signal provided by the triggering stage, the output stage is switched.
Depending on the switching status, the threshold of the triggering stage is also
slightly changed. Thus, the hysteresis of the proximity sensor is created. An output
signal is created if, with the increasing attenuation of the proximity sensor, the
rectified amplitude signal falls below the triggering threshold. With the decreasing
attenuation, a higher amplitude of oscillation is required to switch off the output
signal. In this case the triggering threshold is slightly higher than in the former case
and the proximity sensor indicates hysteresis. Switching distance and
conductivity Amongst other things, the switching distance depends on the electrical conductivity
of the metal to be detected. The following table lists the values in respect of the
conductivity of different metals and a...
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- Spring '12
- pH, proximity sensors, Festo Didactic GmbH, Festo Didactic GmbH & Co