21st October 2019

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# What is 20 mA?

4-20 mA. (4 to 20 MilliAmp) A point-to-point or multi-drop circuit mainly used in the process automation field to transmit signals from instruments and sensors in the field to a controller. It sends an analog signal from 4 to 20 mA that represents 0 to 100% of some process variable.

Also to know is, how many volts are in a mA?

The answer is 0.001. We assume you are converting between watt/volt and milliampere. The SI base unit for electric current is the ampere. 1 ampere is equal to 1 watt/volt, or 1000 mA.

Why the 4 to 20 mA signal is preferred over a 0 10v signal?

Also, a 0-10V signal is susceptible to voltage drops caused by wire resistance, especially over long cable runs. A 4-20 mA or 0-20 mA signal, on the other hand, offers increased immunity to both electrical interference and signal loss over long cable runs. The same can not be said for a 0-10V sensor.

What is 4 to 20 MilliAmp signal?

4-20 mA Current Loop Basics. Sensors or other devices with a 4-20 mA current loop output are extremely common in industrial measurement and control applications. They are easy to deploy, have wide power supply requirements, generate a low noise output, and can be transmitted without loss over great distances.