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5
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8
6
4
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3-2
Section
Connecting Link Adapters
26
When using Host Link or 1:1 NT Link communications, set the RS-422A send
mode to “no RS/CS control” by turn OFF both SW1-5 and SW1-6.
When using 1:N NT Link communications (standard or high-speed), set the
communications mode to “RS/CS control” by turning ON either pin SW1-5 or
SW1-6.
Note
1. Do not turn ON both SW1-5 and SW1-6 at the same time. This may damage
internal circuits.
2. The power supply to the device sup5 V must be turned OFF before
starting wiring work.
3. Before connecting the RS-232C cable and turning ON the power to an
RS-232C device such as a PT (i.e., turning ON the power to the Link Adapt-
er), check that the cable is wired correctly and that the DIP switch settings
are correct. If the power is turned ON and there is a wiring fault, the internal
circuits of the Link Adapter or the RS-232C device may be damaged.
4. When the Link Adapter is connected to a C200HX/HG/HE (-ZE), CQM1H,
CS1G/H, CS1G/H-H, or CJ1G model of OMRON PC as an RS-422A device,
set pins SW1-5 and SW1-6 as indicated below.
5 6
SW1-5
OFF
SW1-6
ON
The NT-AL001-E Link Adapter has a terminal block for an RS-422A/485 inter-
face connection and a connector for an RS-232C interface connection.
The pin allocations for the RS-422A/485 terminal block and the RS-232C con-
nector are as follows.
RS-422A/485 Terminal Block
The CSB and CSA signals are for specialized applications.
Pin
Signal name
Code
Signal direction
(Link Adapter
⇔
Device)
8
Request to send (–)
CSA
Link Adapter
→
RS-422A/485 Device
7
Request to send (+)
CSB
Link Adapter
→
RS-422A/485 Device
6
Receive data (–)
RDA
Link Adapter
←
RS-422A/485 Device
5
Receive data (+)
RDB
Link Adapter
←
RS-422A/485 Device
4
Send data (–)
SDA
Link Adapter
→
RS-422A/485 Device
3
Send data (+)
SDB
Link Adapter
→
RS-422A/485 Device
2
Signal ground
SG (GND)
---
1
Functional ground
---
Compatible Crimp Terminals
Use crimp terminals for M3 screws.
Fork terminal
6.2 mm max.
Round terminal
6.2 mm max.
Manufacturer
Style
Model
Compatible wire
J.S.T. Mfg Co., Ltd.
Fork
V1.25-N3A
AWG22 to AWG16
(0 25
1 65
2
)
g
,
Round
V1.25-MS3
(0.25 to 1.65 mm
2
)
Molex
Fork
VSY1.25-3.5L
AWG22 to AWG16
(0 3
1 6
2
)
Round
RAV1.25-3
(0.3 to 1.65 mm
2
)
Terminal Pin Allocation