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. Tickled can be ensured using so-called signal limiting.
Why is a signal clamping necessary in the first place?
If the pressure on a pressure transmitter lies within the nominal pressure range, then you will have a precise signal output (e.g. 4 ? 20 mA or 0 ? 10 V). However, in technical applications, it frequently happens an originally planned pressure range is exceeded or is dropped below. This may happen deliberately, for instance when cleaning, and also accidentally, for instance through load variations or in case of a fault. In these cases, the sensor signal may also move outside the defined limits, so that, for example, a current signal in the number of 3.6 to 25 mA may appear.
If now, however, the evaluation electronics are set so that they recognise a signal outside the defined limits being an error, in a few situations, trouble-free operation of the entire system cannot be ensured anymore. In such cases, a signal limiting of the pressure transmitter makes sense, so that the output signal is maintained within the mandatory range (e.g. 3.8 ? 21 mA).
Note
Black Market of a pressure transmitter with which the voltage signal as well as the current signal can be limited may be the model S-20 (for general industrial applications) or the model MH-3 (for mobile working machines) from WIKA.

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