GND, Chassi GND and RS-485 GND clarification (Revpi connect)

[jobijobi]

Please see picture attached:

- Is 0V the same net as the GND symbol on the RS-485 connector

- Please clarify the use-cases for the chassi-gnd, i.e. when and when not to use it


Thanks

[dirk]

Hi Yes, 0V (power supply) is the same net as the GND symbol (RS-485 connector).

Use this GND only if a reference potential is necessary or if the common mode range of the RS-485 drivers is exceeded (but usually the differential line pair is sufficient).

Chassis GND is functional earth, here you can connect the shield of a line.