ABB C100 - 2 ELECTRICAL INSTALLATION; 2.2 Two-wire and Four-wire Connection

3
Fig. 2.1a Two-wire Operation – Panel Mounted Instruments
+5V
0V
1.8kΩ Pull-up
Resistor
1.8kΩ Pull-down
Resistor
Host Computer
Rx–
Rx+
Tx–
Tx+
'A'
'A
'B'
'B
GND
20
21
22
23
24
C100/V100
Tx+/Rx+
Tx–/Rx–
GND
C150
2 ELECTRICAL INSTALLATION…
Fig. 2.1b Two-wire Operation – Wall-/Pipe-Mounted Instruments
+5V
0V
1.8kΩ Pull-up
Resistor
1.8kΩ Pull-down
Resistor
Host Computer
Rx–
Rx+
Tx–
Tx+
'A'
'A
'B'
'B
GND
Tx+/Rx+
Tx–/Rx–
GND
11 12 13
…2.2 Two-wire and Four-wire Connection