Omron Programmable Terminals NT31 NT31C Setup Manual page 100

Connecting to the Host's RS-232C Port
Connecting an NT31/NT31C and NT-AL001 (RS-422A)
1
13
Connecting an NT31/NT31C and NT-AL001 (RS-485)
1
14
13 25
Reference: When using RS-485 as a port for the NT31/NT31C, only NT link (1:N) method
NT31/NT31C
RS-422A
NT31/NT31C side
Abbreviation Pin number
14
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
25
−
− −
RSB (+) 23
RSA (−) 24
−
25
(25-pin type)
In order to avoid an FG ground loop, do not make the connection between the
functional ground of the NT-AL001 and the shielding.
NT31/NT31C
RS-485
NT31/NT31C side
Abbreviation
FG
−
SD
RS-232C/
422A/485
RD
connector
RS
CS
−
SG
−
TRM
RDB (+)
SDB (+)
−
−
−
SDA (−)
RDA (−)
−
−
RSB (+)
RSA (−)
−
(25-pin type)
In order to avoid an FG ground loop, do not make the connection between the
functional ground of the NT-AL001 and the shielding.
(standard or high-speed) can be used.
Host
NT-AL001
Shielding wire
NT-AL001 side
Pin number Abbreviation
6 RDA
5 RDB
4 SDA
3 SDB
Functional
1
ground
Host
NT-AL001
Pin number
Connector
hood
1
2
3
4
5
6
7
NT-AL001 side
8
9
Pin number
10
6
11
5
12
4
13
3
14
1
15
16
Shielding wire
−
23
24
25
Section
8
7
6
5
4
3
2
1
RS-422A
terminal
block
7
5
3
1
Abbreviation
RDA
RS-422A
RDB
terminal
SDA
block
SDB
Functional
ground
5-1
8
6
4
2
89