Omron NT20S Operation Manual page 289

Connecting to an RS-232C/RS-422A Converter Unit (1:1)
S RS-422A Cable Wiring
RS-422A
terminal
block
DIP Switch Settings at RS-232C/RS-422A Converter Unit
270
NT-AL001
Abbrev. Pin No.
FG 1
SDA 3
SDB 4
RDA 5
RDB 6
Pin No.
1
3
4
5
6
Shielding
wire
NT-AL001
Abbrev.
FG
SDA RS-422A
terminal
SDB
block
RDA
RDB
Appendix I