Omron Programmable Terminals NT31 NT31C - Manual (Page 134)

5-2 Section Connecting to the Host’s RS-422A/485 Port
123
Reference:
S Communication using the RS-422A type standard NT link (1:N) method is
possible only when a CS1W-SCB41 Serial Communications Board is installed
in a CS1 series CS1G/H, a Communications Board is installed in a C200HX/
HG/HE(-Z)E, or a CQM1H-SCB41 Serial Communications Board is installed
in a CQM1H.
S Communication using the RS-422A type high-speed NT link (1:N) method is
possible only when a CS1W-SCB41 Serial Communications Board is installed
in a CS1 series CS1G/H.
The relay terminal block is not included in this figure. Insert the relay terminal
block so as to achieve the wiring configuration shown below.
:
RS-422A
NT31/NT31C Host
:
1
14
13 25
1
14
13 25
NT31/NT31C side
Shielding wire
(25-pin type)
Abbreviation
FG
−
SD
RD
RS
CS
−
SG
−
TRM
RDB (+)
RDB (+)
−
−
−
SDA ( −)
RDA ( −)
−
−
RSB (+)
RSA ( −)
−
Pin number
Connector
hood
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
−
23
24
25
RS-232C/
422A/485
connector
RS-232C/
422A/485
connector
Abbreviation
FG
−
SD
RD
RS
CS
−
SG
−
TRM
RDB (+)
RDB (+)
−
−
−
SDA ( −)
RDA ( −)
−
−
RSB (+)
RSA ( −)
−
Pin number
Connector
hood
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
−
23
24
25
(25-pin type)
NT31/NT31C side
*2
Make the connection between pin numbers 9 and 10 at the NT31/NT31C at the
end of the RS-422A cable (marked
: in the figure above) only.
In order to avoid an FG ground loop, connect the functional ground of only one of
the NT31/NT31C units to the shielding of the RS-422A cable.
Connecting an NT31/NT31C and a Host
RS-422A
NT31/NT31C Host
Connecting between
NT31/NT31C Units