Again thank you for your help, I am supplying the Y4000 from a dedicated power supply and I have done all the code instruction you gave earlier.
The code is working. However, the sensor is not responding back as you can see in the attached picture. I thought it might be a grounding issue so I have connected the grounding from the sensor with the MKR485 grounding, nothing have changed. Tried to change the modbusAddress = 0x03 into 0x01 as a try, also nothing changed.
If anything comes to your mind on what can be the issue please let me know.