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 critical value. This is often ensured with the aid of 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 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 example when cleaning, as well as 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 can occur.
If now, however, Blushing 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 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
A good 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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