G120C 4-20mA Input Problem

I defined 4-20mA through terminals 3-4.

Once I apply more than 15.4mA through terminals 3-4, I can read exactly same value from driver but once I apply less Amps I still get 15.3mA reading from driver. Even if I remove the cables from terminals 3 & 4 I still get 15-16mA reading from driver.

Is there any parameter or wiring which could cause that or we can say Analog/Digital converter part of the driver is faulty?

Technology Team

Hello ENVER58,

make sure you have set the DIP switch of the G120C to current measuring setting.
You can find an example how to set up the analog input for current input signals in chapter 8.4.6 of the G120C operating instruction manual.
https://support.industry.siemens.com/cs/ww/en/view/109782995

To check that the input is working check parameter r0752 of the G120C, which provides the actual analog input value on the analog input.
See attached function diagram 2250 of the G120C for details about the AI.

 Thanks for the reply. DIP switch is already set, that is how I can get 16 and 20mA correctly.

As I mentioned even if I don't inject anything (no cable connection on terminals 3-4) I am reading 15-16mAmp from parameter r0752. Once I inject more than 15.4mA, I start getting correct reading.