Signal clamping in pressure transmitters

In certain applications, the existing 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 a sign clamping necessary to begin with?
If the pressure on a pressure transmitter lies within the nominal pressure range, then there will be a defined 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 example through load variations or in case of a fault. In these 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 may appear.
If now, however, the evaluation electronics are set so they recognise a signal outside the defined limits being an error, in some situations, trouble-free operation of the complete system cannot be ensured anymore. In Intel , 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
A good example of a pressure transmitter with which the voltage signal and also 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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