Is it necessary to connect isolated grounds for 2 different isolated RS485 nodes? For instance the following isolated RS485 breakout board doesn't have any GND connection in the board.
If I connect them together, will it improve the performance in a noisy environment?
According to my understanding signal ground is non isolated part of the supply as shown in figure. Is there anything wrong if I connect signal GND to chassis GND and connecting all isolated GNDs together(Without connecting to signal GND)?
Please correct me if I am wrong.