And for a non galvanic isolation RS485 still all the
0v commons of the circuit should be tied together . And to the DIRT at one end only the MASTER END is it true for this aswell .


SHIELD where to tie it incase of non galvanic isolation situation .To the circuit common if PE isnt available , Then what is the need of third wire 0v .


ALL the Noise will couple to the Circuit common if tied to shield .


Any Leftover twisted pair in the cable what to do with em ,I hope they will resonate to some frequency ,and if grounded at one end would still resonate ,what to do .

Sorry I ask too much .

Kindly/