Pressure switches are crucial components in a wide range of industries and applications. They serve as the guardians of pressure-sensitive systems, ensuring they operate within safe and optimal parameters. While traditional mechanical pressure switches have been the go-to choice for many years, electronic pressure switches are gaining ground as technology advances. In this article, we’ll explore the advantages of electronic pressure switches and help you understand when it’s best to switch to electronic pressure control.
How Does an Electronic Pressure Switch Work?
An electronic pressure switch is a pressure sensing instrument that employs a pressure sensor (transducer) as well as conditioning electronics capable of providing a switch output (“open” or “close” circuit) via a relay or NPN/PNP output.
Electronic pressure switches can also have a local LED/LCD display with push buttons for customizing the outputs. An analog output (e.g., 4-20 mA or voltage output) can also be provided with an electronic pressure switch. In many circumstances, your application, whether process, industrial, or OEM, will decide its utilization.
Hydraulic presses, tire press vulcanization, water/wastewater pressure management, refrigerant/ammonia-based cooling systems, alarms, control, and pressure monitoring all require electronic pressure switches. They are also useful for level monitoring, such as tank level applications, in which the switch transmits a signal whether the tank is full or low, causing an analog output to turn a pump on or off.
Electronic pressure switches differ from mechanical switches in various aspects. To begin, they require a power supply (DC voltage) to function and run, which an end user may or may not have, depending on their use.
Optional features may include a local display with buttons for configuring the device, as well as the ability for the user to field program them with no additional instrumentation.
A mechanical switch, on the other hand, will necessitate the use of a secondary, more accurate instrument to confirm that its set point has been properly calibrated. Electronic pressure switches are typically more expensive than their mechanical counterparts.
When Would You Use an Electronic Switch?
Electronic switches are generally used on industrial, OEM, or process-type applications for high/low alarms, control, pressure monitoring, and automation. They are also commonly used with PLCs and other building control devices.
Electronic switches also are more accurate and repeatable than mechanical switches, making them ideal for applications where accuracy is of the utmost importance.
When compared to mechanical switches, electronic pressure switches have a longer lifespan. They can sustain more pressure cycles because they are built with fewer moving parts, making for less wear and tear to the diaphragm.
In an electronic pressure switch, the diaphragm of the pressure sensor is the only moving part. Mechanical switches have springs, pistons, and other moving parts, which can cause more wear and tear over time, leading in a shorter lifespan.
Advantages of Electronic Pressure Switch
- LCD/LED local display
- Programmable in the field
- Easy to use
- Setup is simple and requires no additional measurement instruments.
- Can program a timer/delay/hysteresis
Mechanical switches are used as pass-through devices. They are commonly used in applications that use AC voltages, where an end user may be unable to provide a power source to an electronic pressure switch.
Mechanical switches have range restrictions and often have predetermined reset points, which is referred to as a dead band. In contrast, electronic switches can be programmed to set and reset practically anywhere in the range of the device.
What Characterize a High-Quality Electronic Pressure Switch?
Take note of the case material enclosure. Enclosure material can play a significant part in the cost or quality of the electronic pressure switch, depending on how exotic or familiar the material is.
Typical weather-proof classifications in the industry include IP66 or IP67-rated enclosures, making them ideal for situations where rain or snow may fall.
Other factors include the types or amounts of outputs, the static accuracy of the switch, and whether it provides communication protocols (e.g., HART, IO-Link, etc.) or other diagnostic/troubleshooting tools. Bluetooth connections are even available on some electronic switches.
The more bells and whistles you put on your switch, the more expensive it will be. It depends on your application if you need all the extra accouterments, but for most processes, you can get away with a more budget-friendly and straightforward option.
In Europe, a quality switch will also have general safety approvals/listings like UL and CE. These switches meet specified electronic specifications, are lead-free, and can assist in reducing radio frequency interference.
Temperature compensation is another feature that distinguishes a high-quality electronic pressure switch. This is the measure for counteracting/correcting an unwanted temperature effect, ideally eliminating temperature effects on the sensor.
The resolution of the display and how many digits it can display (to what decimal place) should also be taken into consideration when looking for a high-quality electronic pressure switch.
In conclusion, knowing when to use an electronic pressure switch can be crucial for various applications. Whether it’s in industrial settings, HVAC systems, or even home automation, understanding the specific conditions and requirements that necessitate this technology will ensure optimal performance and safety. By considering factors like pressure levels, precision, and control, you can make informed decisions and leverage electronic pressure switches to enhance efficiency and reliability in your systems.