Mechanical vs. electronic pressure switches: Functionality

How can you decide whether to utilize mechanical pressure switches or electronic pressure switches in the application? Each type of pressure switch has individual advantages, but additionally its limitations. The main differences in functionality between mechanical and electronic pressure switches will be the way the applied pressure can be used to use the switch, the kind of switch technology, and how the switch point can be adjusted.
Functionality of mechanical pressure switches
A mechanical pressure switch converts the pressure of a fluid 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 an electrical switching signal, but will not need a voltage supply.
Ordinarily, mechanical pressure switches are simple devices which are either created for cost-effective applications or optimised for long-term use, based on how usually 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 normally 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 often 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’re 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 enables 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 neighborhood display of an electronic pressure switch also provides a continuous pressure indication and shows if the switch outputs are active or not. Last but not least, modern technologies, including the usage of IO-Link, enable programming remotely via signal cables.
Note
Further information on mechanical pressure switches and electronic pressure switches can be found on the WIKA website.
Also read Masterclass : Application areas
Mechanical pressure switches: So how exactly does one set the switch point?
Pressure switches in booster pumps

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