In industrial equipment, the pressure switch is a very common component. Its function is simple: when the pressure reaches a certain value, the switch activates, controlling equipment to start or stop. However, many people are unaware that pressure switches actually come in three types: mechanical, electronic with digital display, and electronic without digital display. Today, we will explain the differences between these three types of pressure switches in the most straightforward way, helping you select the most suitable one for your application.
I. Differences in Working Principle
1. Mechanical Pressure Switch:
Inside a mechanical pressure switch, there is a spring and a diaphragm. When pressure is applied, the diaphragm pushes against the spring. When the pressure reaches the set point, the spring is compressed to a certain degree, which triggers the switch, completing the on/off action. The entire process relies purely on physical force transmission and contains no electronic components.
2. Electronic Pressure Switch with Digital Display:
An electronic pressure switch with a digital display contains a pressure sensor and a dedicated conditioning circuit inside. The sensor continuously senses pressure changes and converts the pressure into an electrical signal. The dedicated conditioning circuit compares this signal with the user‑set pressure value. Finally, the command is output through an electronic switch. The biggest difference from a mechanical switch is that it has a built‑in digital screen that displays the current pressure value in real time, as well as several buttons for on‑site parameter setting.
3. Electronic Pressure Switch without Digital Display:
An electronic pressure switch without a digital display has the same internal structure as the version with a display: it includes a sensor and a dedicated conditioning circuit, and possesses the same intelligent judgment capability. However, it has no screen and no buttons. Parameter setting is typically done via RS485 communication using a computer, PLC, or HMI to send commands. Parameters can also be read via communication or through a 4‑20 mA analog output connected to a display. The main difference from the electronic version with a display is that the non‑display version is usually more compact, making it suitable for confined spaces or locations where on‑site adjustment is inconvenient, while still allowing remote pressure reading and adjustment.
The following table clearly compares the three types:
| Comparison Item | Mechanical Pressure Switch | Electronic Pressure Switch with Digital Display | Electronic Pressure Switch without Digital Display |
|---|---|---|---|
| Working Principle | Spring + diaphragm mechanical triggering | Sensor + conditioning circuit, intelligent judgment | Sensor + conditioning circuit, intelligent judgment |
| How to Set Pressure | Adjust spring with a screwdriver while watching a gauge | Enter value directly using keypad buttons | Send command via RS485 communication |
| Can Current Pressure be Seen? | No, requires an external pressure gauge | Yes, displayed directly on screen | Via communication readout or analog output |
| Adjustment Convenience | Requires skilled personnel on site | On‑site personnel can learn in minutes | Remote centralized setting, no need to go to the site |
| Accuracy | General, susceptible to spring fatigue and temperature | High, long‑term stability with no drift | High, long‑term stability with no drift |
| Output Signal | Single switching output | Switching + analog + communication (optional) | Switching + analog + communication (optional) |
| Vibration Resistance | General, spring and contacts are vibration‑sensitive | Good, no mechanical wear parts | Good, no mechanical wear parts |
| Protection Rating | Typically IP65 or similar | Typically IP65 | Can reach IP67 / IP69K |
| Size | Medium | Slightly larger | More compact |
| Power Supply Required | No (some models) | Yes | Yes |
| Price | Lower | Higher | Medium |
II. Application Scenarios
1. Mechanical Pressure Switch
·Tight budget constraints
·Simple equipment environment with little vibration
·No need for remote pressure monitoring
·On‑site personnel prefer traditional methods
·Equipment operates independently, not connected to a control system
2. Electronic Pressure Switch with Digital Display
·Need to frequently adjust the setpoint
·Want on‑site personnel to see the current pressure directly
·Equipment needs to output an analog signal to a PLC
·Stand‑alone equipment requiring on‑site commissioning
3. Electronic Pressure Switch without Digital Display
·Limited equipment space, cannot accommodate a switch with a display
·Humid, dusty environment requiring a high protection rating
·Multiple pressure switches used on a single piece of equipment
·Equipment is centrally monitored via a PLC or HMI
·Parameters are rarely changed after setting, but long‑term stability and reliability are essential
III. lection Recommendations
If lowest cost and no power supply are the top priorities → Choose a mechanical pressure switch
If you need to see the pressure on site, adjust parameters on site, and have rich functionality → Choose an electronic pressure switch with digital display
If you need a compact size, high protection rating, remote centralized control, and batch usage → Choose an electronic pressure switch without digital display
With industrial automation becoming increasingly intelligent, electronic pressure switches are gradually replacing traditional mechanical products. However, the specific choice should still be based on actual requirements and on‑site conditions.
If you are struggling to select the right pressure switch for your equipment, please contact us. We can recommend the most suitable pressure switch solution based on your specific operating conditions.
