Siemens SIMATIC S7-300 Manual page 419

Block diagram of the RS 485 Repeater
● Bus segments 1 and 2 are electrically isolated.
● Bus segment 2 and the PG/OP socket are electrically isolated.
● Signals are amplified
①
②
③
④
S7-300 Automation System Module data
Manual, 08/2006, A5E00105505-04
– between bus segments 1 and 2
– between PG/OP socket and bus segment 2
3
Segment 1
Segment 2
PG/OP socket
PG/OP socket
RS 485 Repeater
9.4 Technical data
9-7