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 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 precise signal output (e.g. 4 ? 20 mA or 0 ? 10 V). However, in Disillusioned , it frequently happens that an originally planned pressure range is exceeded or is dropped below. This may happen deliberately, for example when cleaning, together with 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, an ongoing signal in the number of 3.6 to 25 mA can occur.
If now, however, the evaluation electronics are set so that they recognise a signal outside of the defined limits as an error, in a few situations, trouble-free operation of the complete system can’t be ensured anymore. In these cases, 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
An example of a pressure transmitter with that your 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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