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5-2
Section
Connecting to the Host’s RS-232C Port
96
Compatible Cables with Attached Connectors:
XW2Z-070T-1
(9-pin to 9-pin, 0.7 m)
XW2Z-200T-1
(9-pin to 9-pin, 2 m)
6
5
9
1
6
5
9
1
Shield
Abbreviation
FG
–
SD
RD
RS
CS
+5V
–
–
SG
Pin number
Connector
hood
1
2
3
4
5
6
7
8
9
(9-pin
connector)
Link Adapter
NT21
RS-232C
connector
RS-232C
terminal
block
Pin number
Connector
hood
1
2
3
4
5
6
7
8
9
Abbreviation
FG
–
SD
RD
RS
CS
+5V
–
–
SG
(9-pin
connector)
When an NT-AL001 Link Adapter is being used, the RS-232C cable can be con-
nected to either serial port A or B on the NT21.
When an NS-AL002 Link Adapter is being used, the Link Adapter connects di-
rectly to serial port B on the NT21, so an RS-232C cable is not required.
Connecting the NT21-side Link Adapters to the Host-side Link Adapter (RS-422A)
NT21
Host
NT-AL001
RS-422A
(Total length
500 m max.)
Link Adapters
(NT-AL001 or
NS-AL002)
Shield
NS-AL002
NT-AL001
Pin number
Abbreviation
F. Ground
SG
SDB
SDA
RDB
RDA
CSB
CSA
DIP Switch Settings
NT-AL001:
Pins 1 and 6 ON
Pins 2 to 5 OFF
NS-AL002:
Pin 1 ON
Pins 2 to 4 OFF
RS-422A
terminal
block
NT-AL001
1
2
3
4
5
6
7
8
NS-AL002
1
---
3
7
2
6
---
---
Pin number
1
2
3
4
5
6
7
8
Abbreviation
F. Ground
SG
SDB
SDA
RDB
RDA
CSB
CSA
DIP Switch Settings
Pins 1, 2, and 6 ON
Pins 3 to 5 OFF
RS-422A
terminal
block
NT-AL001 or NS-AL002 Link
Adapter (NT21)
NT-AL001 Link Adapter
(Host)
To next PT
7
5
3
1
8
6
4
2
To avoid an FG ground loop, do not connect the functional ground of the Link
Adapter at the NT21 to the RS-422A cable shielding.