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 crucial value. This is often ensured with the aid of 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 ? Exploit 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, along with 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, in order that, for example, a current signal in the number of 3.6 to 25 mA can occur.
If now, however, the evaluation electronics are set so they recognise a signal outside of the defined limits as an error, in some situations, trouble-free operation of the entire system can’t be ensured anymore. In these cases, a sign limiting of the pressure transmitter makes sense, 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 as well as the current signal can be limited is the model S-20 (for general industrial applications) or the model MH-3 (for mobile working machines) from WIKA.

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