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3-2
Section
Connecting Link Adapters
20
Communications Specifications (RS-422A/485 Interface)
Item
Specification
Baud rate
115.2k bps max. (depends on the RS-232C baud
rate)
Transmission distance
500 m max.
Terminal block configuration
8-terminal detachable terminal block, M3.0
Insulation
Non-insulated (See note.)
Note The RS-422A/RS-485 connector is not insulated from the RS-232C connector.
The NS-AL002 Link Adapter has a 4-pin DIP switch that sets the RS-422A/
RS-485 communication conditions. Set the DIP switch before connecting the
communications cable.
ON
OFF
The following table shows the functions of the DIP switch pins. The factory de-
faults are OFF for all 4 pins.
Pin(s)
Function
ON
OFF
1
Communications mode
RS/CS control
No RS/CS control
2 and 3
Communications method
2-wire (RS-485)
4-wire (RS-232C)
4
Terminating resistance
Terminator ON
Terminator OFF
When using 1:1 NT Link communications, set the communications mode to “No
RS/CS control” by turning OFF pin 1.
When using 1:N NT Link communications (standard or high-speed), set the
communications mode to “RS/CS control” by turning ON pin 1.
The Link Adapter has an RS-232C connector and a terminal block for an
RS-422A/485 interface connection. The pin arrangements for the RS-232C con-
nector and the RS-422A/485 terminal block are as follows.
RS-232C Connector
Pin
Signal name
Code
Signal direction
(Link Adapter
⇔
NT21)
1
Not used
---
---
2
Receive data
RD
Link Adapter
←
NT21
3
Send data
SD
Link Adapter
→
NT21
4
Clear to send
(shorted to RS internally)
CS
Link Adapter
←
NT21
5
Request to send
(shorted to CS internally)
RS
Link Adapter
→
NT21
6
+5 V (30 mA) input for
Link Adapter
+5 V
Link Adapter
←
NT21
7 and 8
Not used
---
Pins 7 and 8 are shorted
internally
DIP Switch Settings
Pin Allocation
Содержание NT21
Страница 1: ...Cat No V068 E1 01 Programmable Terminal NT21 Setup Manual ...
Страница 2: ...NT21 Programmable Terminal Setup Manual Produced October 2001 ...
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Страница 222: ...Cat No V068 E1 01 Note Specifications subject to change without notice Printed in Japan Authorized Distributor ...