Mechanical vs. electronic pressure switches: Functionality

How can you decide whether to utilize mechanical pressure switches or electronic pressure switches in your application? Each kind of pressure switch has individual advantages, but additionally its limitations. The main differences in functionality between mechanical and electronic pressure switches are the way the applied pressure can be used to use the switch, the type of switch technology, and the way the switch point could be adjusted.
Terrified of mechanical pressure switches
A mechanical pressure switch converts the pressure of a fluid right into a mechanical movement that actuates the mechanical switch contact in the pressure switch. The switch has the preset or an individually, mechanically adjustable switch point. Every time the switch is actuated, a mechanical pressure switch sends a power switching signal, but does not require a voltage supply.
Ordinarily, mechanical pressure switches are simple devices which are either created for cost-effective applications or optimised for long-term use, depending on how often the switching signal should be transmitted. The switches are thus designed either for a low application rate (hardly any switching cycles e.g. in safety applications) or for a higher application rate (frequent switching changes e.g. in process control). The hysteresis is usually not adjustable, thus the reset point for switching cannot be configured and is preset by factory setup.
Mechanical pressure switches can be used to switch high currents, such as pumps and drives. However, mechanical contacts frequently have problems switching the very low voltages in PLCs and modern electronics, unless expensive, gold-plated switch contacts are employed.
Functionality of electronic pressure switches
An electric pressure switch generates electronic switching signals and, very often, also yet another, analogue output signal proportional to the pressure. They are either programmed at the factory to the required switch points or they include a programming interface with integrated display and buttons.
Electronic pressure switches have integrated, programmable logic. This permits the switch points and the output signal to be adapted to the application-specific needs. Delay time, switch point, reset switch point, hysteresis or window function, normally closed or normally open, and many more functions can be programmed in modern electronic pressure switches.
The local display of an electric pressure switch also provides a continuous pressure indication and shows whether the switch outputs are active or not. No Risk but not least, modern technologies, such as the use of IO-Link, enable programming remotely via signal cables.
Note
More info on mechanical pressure switches and electronic pressure switches can be found on the WIKA website.
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Mechanical vs electronic pressure switches: Application areas
Mechanical pressure switches: So how exactly does one set the switch point?
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