1:N Connection Among Rs-422A Ports - Omron Programmable Terminals NT31 NT31C Setup Manual

Connecting to the Host's RS-422A/485 Port
1
13

5-2-4 1:N Connection among RS-422A Ports

122
14
NT31/NT31C side
Abbreviation Pin number
Connector
FG
hood
−
1
RS-232C/ SD 2
422A/485
RD 3
connector
RS 4
CS 5
−
6
SG 7
−
8
TRM 9
RDB (+) 10
SDB (+) 11
−
12
−
13
−
14
SDA (−) 15
25
RDA (−) 16
−
− −
RSB (+) 23
RSA (−) 24
−
25
(25-pin type)
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.
The connection method in which the RS-422A ports of multiple NT31/NT31Cs
and one host are connected in a 1:N connection is described here.
24V
DC
PRINTER PORT B
C200HX-CPU65-ZE
CQM1H-CPU51
PC (CPU) side
Pin number Abbreviation
Shielding wire
Connector
FG
hood
1
SDA (−)
RS-422A
connector
2 SDB (+)
−
3
−
4
−
5
6 RDA (−)
−
7
8 RDB (+)
−
9
(9-pin type)
NT31/NT31C
Serial port B
(RS-422A, 25-pin
type)
25-pin connector
Relay terminal block
Max. 2 m
RS-422A cables
(max. total length 500 m)
Section 5-2
C200HX-CPU85-ZE
CQM1H-CPU61
6
1
9
5
CPU
CS1G/H
C200HX/HG/HE(-Z)E
CQM1H
9-pin connector