🔧 Understanding Pressure Transmitter Signal Conversion (4–20 mA to Engineering Units)

In the world of industrial automation, analog signals play a vital role in communicating real-world process variables to the PLC. A common example is pressure measurement using a 4–20 mA signal.

📌 Here’s how it works:

A pressure transmitter with a range of 0 to 10 bar sends a 4–20 mA signal to the PLC's analog input. The PLC then converts this signal into engineering values (bar), which can be visualized on the HMI or SCADA system.

✅ Conversion Breakdown:

4 mA ➡️ 0 bar ➡️ 0%

12 mA ➡️ 5 bar ➡️ 50%

20 mA ➡️ 10 bar ➡️ 100%

This method ensures accurate, real-time monitoring of field parameters and is essential for process control and automation.

🧠 Did You Know?
4 mA is used as the "live zero" to differentiate between zero pressure and a broken wire (0 mA).