4-20mA

4-20mA Current Loop Connection

Analog signals, where information about the process is transmitted via varying amounts of voltage or current, are the predominant type of input in industries requiring process control today.

A major application of current loops is the industry standard 4-20 mA current loop for process control applications, where they are extensively used to carry signals from process instrumentation to PID controllers, SCADA systems, and Programmable logic controllers.