87
Connecting to the Host’s RS-232C Port Section 5-1
Connecting an NT31/
NT31C and NT-AL001 (RS-
422A)
The relay terminal board is not included in the figure below. Insert a relay ter-
minal board so as to achieve the wiring configuration indicated below.
For details on handling shield wires, refer to 5-2-8 Handling the Shield on RS-
422A/485 Cables on page 128.
RS-422A
NT31/NT31C
Host
NT-AL001
1
14
13 25
7
5
3
1
8
6
4
2
NT31/NT31C side
Next PT
NT-AL001 side
Shielding wire
(25-pin type)
FG
−
SD
RD
RS
CS
−
SG
−
TRM
RDB (+)
RDB (+)
−
−
−
SDA (-)
RDA (-)
−
−
RSB (+)
RSA (-)
−
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
−
23
24
25
Pin number
6
5
4
3
1
Abbreviation
RDA
RDB
SDA
SDB
Abbreviation
Pin number
RS-232C/
422A/485
connector
Connector
hood
RS-422A
terminal
block
Functional
ground