Figure 6-11 Rs 485 Terminal Block; Figure 6-12 Block Diagram: General Rs 485 Topology - Siemens SENTRON PAC3100 Manual

RS 485 terminal block
COM
+/B
-/A
Figure 6-11
Block diagram
TER Bus termination resistor (termination)
PU Pull-up resistor
PD Pull-down resistor
(1) Grounding of the cable shielding
(2) Grounding of the common line, preferably only at one point for the whole bus
Figure 6-12 Block diagram: General RS 485 topology
SENTRON PAC3100
Manual, 07/2009, A5E02385159B-01
Common = Ground
B signal; D1
A signal; D0
RS 485 terminal block
Connection
6.5 Connecting to the RS 485 bus
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