Signal clamping in pressure transmitters

In certain applications, the existing or voltage signal of a pressure transmitter must not exceed and/or drop below a crucial value. This could be ensured using so-called signal limiting.
Why is a signal clamping necessary to begin with?
If the pressure on a pressure transmitter lies within the nominal pressure range, then you will see a precise signal output (e.g. 4 ? 20 mA or 0 ? 10 V). However, in technical applications, it frequently happens that an originally planned pressure range is exceeded or is dropped below. This may happen deliberately, for example when cleaning, in addition to accidentally, for instance through load variations or in case of a fault. In such cases, the sensor signal will also move beyond your defined limits, in order that, for example, a current signal in the range of 3.6 to 25 mA can occur.
If now, however, the evaluation electronics are set so they recognise a signal outside the defined limits being an error, in a few situations, trouble-free operation of the complete system can’t be ensured anymore. In Confess , a signal limiting of the pressure transmitter is practical, so the output signal is maintained within the required range (e.g. 3.8 ? 21 mA).
Note
An example of a pressure transmitter with which the voltage signal plus the current signal could be limited is the model S-20 (for general industrial applications) or the model MH-3 (for mobile working machines) from WIKA.

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