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Pressure Switches and Pressure Transmitters

Pressure Switches and Pressure Transmitters two common devices used in process control and automation. 

thought this comparison would be useful, especially for those working with DCS/PLC systems or new to instrumentation.



Pressure Switch

1. Works like a simple ON/OFF switch.

2. Provides a digital signal (either ON or OFF).

3. Activates or deactivates an electrical contact when the pressure crosses a pre-set limit.

4. Used for basic control applications (e.g., turning pumps or compressors ON/OFF).

5. Suitable where only a threshold action is required, not continuous monitoring.


Pressure Transmitter

1. A more advanced pressure-measuring device.

2. Continuously measures the actual pressure value.

3. Provides a continuous analog output signal (typically 4-20 mA or 0-10 V).

4. Used in process control systems like DCS, PLC, or SCADA.

5. Essential for applications needing accurate, real-time pressure data.


In Short


Pressure Switch Only indicates if pressure is too high or too low (ON/OFF).


Pressure Transmitter Continuously tells you the exact pressure value. Pressure Switches and Pressure Transmitters-two common devices used in process control and automation.

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