Electronic pressure switches Vs mechanical pressure switches

So you're in the market for a pressure switch, but should you go electronic or mechanical? Each has its benefits and drawbacks, as PIF explains in this in-depth comparison.

How do mechanical pressure switches work?

Mechanical pressure switches convert fluid pressure into a mechanical movement, which actuates a mechanical switch contact in the pressure switch device. The switch will have a configurable or pre-set mechanical adjustment of the switch point and provides an electrical switch output signal whenever it is actuated – without needing a power supply.

These generally simple devices are normally built for reliability or with low-cost applications in mind. It depends on how frequent the switch signal needs to be transmitted. For instance, they can either be designed for high demand (involving frequent switching cycles, such as in process control) or low demand (requiring minimal switching cycles, like in safety applications). Mechanical pressure switches do not normally allow for adjustment of the hysteresis and the reset point for switching is pre-set by factory setup, so cannot be configured either.

When to use a mechanical pressure switch

When price and single switch contacts are the primary concern, mechanical pressure switches can be the ideal choice. They are also perfect for safety critical applications that require a redundant, and largely dormant, safety guard that provides an instant switch signal when pressure crosses a certain pre-set threshold. They are not first choice in electronic systems for process control however, due mechanical wear and resulting premature failures.

How do electronic pressure switches work?

Electronic pressure switches provide electronic switch output signals. They often also produce an additional analogue output signal proportional to the pressure. Electronic pressure switches are factory set to optimal switch points or are programmable on-site thanks to integrated displays and buttons. Their integrated programmable logic allows for the switch points and output signal to be tailored to the application.

Among the many programmable functions of modern electronic pressure switches are hysteresis, delay time, normally closed or normally open and window function. They also provide constant pressure readings and indicate whether the switch outputs are active or not. IO-Link technology can also be used for remote programming via the signal cable.

When to use an electronic pressure switch

Electronic pressure switches are suitable for applications that demand stability, multiple switch points and flexibility of control – such as for control and automated equipment. They are the desired choice for installations requiring flexible programming and adjustment, local indication display and extra analogue output signals.

Whatever your application, Barksdale has the mechanical and electronic switch solution for you. For instance, their brand new BPS3000 Electronic Dual Pressure Switch features a 320-degree rotatable 4-digit display, multiple configurations and EMI protection. They also have an extensive range of mechanical pressure switches, including: Metal Diaphragm Vacuum and Pressure Switches; compact pressure switches; OEM Diaphragm Seal Piston Pressure Switches; and Bourdon Tube Pressure Switches to name but a few.

For more information about Barksdale’s full range of switch products please contact 01256 799721 or visit www.barksdale.co.uk.