CONTREX CX-1200 - Manual (Page 40)

2-26
Figure 34 CX-1200 Serial Communications Connections
1. Shield only at one end of the cable.
2. If you need to terminate the communication line, then
terminate it at the unit which is the furthest away from
the converter. A 100 ohm, 1/2 Watt resistor will usually
terminate successfully. Refer to EIA Standard
RS-485A, for more information.
RS232 to RS485
Converter
2
1
CX-1200 #1
- TXD/RXD
COM
J1
+ TXD/RXD
CX-1200 #2
1
2
3
- TXD/RXD
COM
J1
+ TXD/RXD
TXD/ TXD/
1
3
2
COM RXD RXD
- +