I've got a project coming up that's to be doing RS-485 communications over shielded twisted pair cable. The project will involve cable length runs of many 10s of ft and the cables will probably have to be laid in a single conduit containing 36VDC wiring to motors. It is unlikely the motor power cable will have a shield.
Regarding the shield in the twisted pair cable, should it be tied to ground at one end, both ends or not at all? What practical difference with this make?
Then if tied to ground, should it be to the board's electrical ground or the chassis earth?