Signal clamping in pressure transmitters

In certain applications, the current or voltage signal of a pressure transmitter should never exceed and/or drop below a critical value. This is often 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 defined 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, and accidentally, for example through load variations or in the event of a fault. In these cases, the sensor signal will 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 they recognise a signal outside of the defined limits being an error, in some situations, trouble-free operation of the entire system cannot be ensured anymore. In such cases, a sign limiting of the pressure transmitter is practical, so the output signal is maintained within the required range (e.g. 3.8 ? Competitive ).
Note
An example of a pressure transmitter with that your voltage signal plus 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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