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 can be ensured using so-called signal limiting.
Why is Gambling 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 instance when cleaning, as well as accidentally, for instance through load variations or in case of a fault. In these cases, the sensor signal may also move beyond your defined limits, so that, for example, a current signal in the range 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 as an error, in some situations, trouble-free operation of the complete system cannot be ensured anymore. In such cases, a sign limiting of the pressure transmitter is practical, in order that the output signal is maintained within the mandatory 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 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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