Omron NT31 Operation Manuals page 145

Connecting to the Host's RS-422A/485 Port
134
S Wiring when connecting CPM1, SRM1
Applicable units:
CPM1-10CDR-j
CPM1-30CDR-j
CPM1A-10CDj-j
CPM1A-30CDj-j
SRM1-C02-V1
1
14
13 25
In order to avoid an FG ground loop, do not connect the functional ground of the
NT31/NT31C to the shielding of the RS-422A cable.
NT31/NT31C side
Abbreviation Pin number
Connector
FG
hood
−
1
SD 2
RS-232C/
422A/485
RD 3
connector
RS 4
CS
5
−
6
SG 7
−
8
TRM 9
RDB (+) 10
SDB (+)
11
−
12
−
13
−
14
SDA (−) 15
RDA (−) 16
−
Shielding wire
− −
RSB (+) 23
RSA (−) 24
−
25
(25-pin type)
Section 5-2
CPM1-20CDR-j
CPM1A-20CDj-j
CPM1A-40CDj-j
PC side
Abbreviation
FG
SG
RS-422A
SDB (+)
terminal
SDA (−) block
RDB (+)
RDA (−)
(9-pin type)
FG
SG
SDB
SDA
RDB
RDA