Why we use 4-20mA current signals instead of voltage?

This video has answered this question:



this question has always made me wonder, but now I got the answer. If you have other points more than the ones mentioned, please contribute.

Best regards!

Replies

  • Carl Ellis
    Carl Ellis
    THE Number One reason for using 4-20mA current signal is for loop powered instrumentation requiring only 2 conductors/wires from the 'control room' receiver to the field. The minimum 4mA value allows 3.5mA or 3.6mA to be used to power the instrument, without additional power conductors.

    The other cited reasons are indeed advantages of a current loop over voltage, but are not the main reason 4-20mA has such widespread acceptance and useage; the main reason is loop power functionality.
  • Piyush Yadav
    Piyush Yadav
    Excellent explanation with in the video but i know about 4-20mA Loop powered sensors, those are mostly used for Vibration measurement for process control system...as there are many variation in instrumentation and their features that's why i uploaded a picture, you may recognise them...
  • Nate Pulkar
    Nate Pulkar
    What is the difference between 4-20 Current Receivers and 4-20 Current loop Receivers and which is much better for industrial standards

You are reading an archived discussion.

Related Posts

Here is another educational video of 2 mins showing the difference between a switch, a transmitter, and a gauge. These terminologies are so important in industrial environment and this video...
Current mirror is a type of constant current circuits but it got its name due to the fact it outputs a current that is equal (or a multiply of) another...
Hi again, Here it is: I hope you like it.
Hi All, Quite a long time since my last post. Anyways, now that I am pursuing my PhD in Computer science, the question that I am going to ask seems...
The entry-level smartphone market in India is catching up. With smartphones like the Redmi 4 and Redmi 4A people are getting more value for their money in an entry-level handset....