Features
• Mount a total of up to 16 CPU Bus Units, including these Serial Communications Units, to the CPU Rack or Expansion Racks to create systems with up to 32 serial communications ports.
• Connect an NT-AL001 RS-232C/RS-442A Link Adapter to the RS-232C port to enable 1:N communications.
• With the CJ1W-SCU[]2, you can use a faster baud rate (up to 230.4 kbps) and faster data transfer to the CPU Unit to enable connecting to high-speed external devices.
Specification
| Item | Description |
| Device name | Serial Communications Unit |
| Classification | CPU Bus Unit |
| Model number | CJ1W-SCU22 | CJ1W-SCU32 | CJ1W-SCU42 | CJ1W-SCU21-V1 | CJ1W-SCU31-V1 | CJ1W-SCU41-V1 |
Serial
ports | Port 1 | RS-232C | RS-422A/485 | RS-422A/485 | RS-232C | RS-422A/485 | RS-422A/485 |
| Port 2 | RS-232C | RS-422A/485 | RS-232C | RS-232C | RS-422A/485 | RS-232C |
| Protocol | Port 1 | Host Link, protocol macro, Serial Gateway, No-
protocol, NT Link, Modbus-RTU Slave, loopback
test , or 1:1 Host Link can be selected for each
port. *1, *2 | Host Link, protocol macro, NT Link, or loopback test can be
selected for each port.
Unit Ver. 1.2 or later also supports Serial Gateway, no-
protocol, and 1:1 Host Link modes. (Note: The Serial Gateway
can also be executed in protocol macro mode.) *1
Unit Ver. 1.3 or later also supports Modbus-RTU slave mode. |
| Port 2 |
Number
of
mountable
Units | CPU Unit | None |
| CPU Rack | A total of up to 16 Units, including all other
CPU Bus Units. No
restrictions on the mounting location.
However, if an external interrupt task is used,
the Unit must be mounted in one of the
following slots on the CPU Rack.
CJ2H-CPU6[]-EIP CPU Unit: Slots 0 to 3
CJ2H-CPU6[], CJ2M-CPU[][] or CJ1G/H-
CPU[][]H CPU Unit: Slots 0 to 4
CJ1M-CPU[][] CPU Unit: Slots 0 to 2
External interrupt tasks will not be started if
the Unit is mounted to any other slot. | A total of up to 16 Units, including all other CPU Bus Units.
No restrictions on the mounting location. |
Expansion
Rack |
Data
exchange
with the
CPU Unit | Ordinary
refreshing
of software
switches
and status | Allocated 25 words of the 25 words in the CPU Bus Unit CIO Area (constant data exchange with the CPU Unit) |
Transfer
from the
CPU Unit
set by the
system | Of the CPU Bus Unit DM Area, each serial port is allocated 10 words (total 20 words).
Data is transferred from the CPU Unit at the following times:
Startup or restart
Ladder instruction: STUP (237)
Port Settings Changing Flag turns ON (Auxiliary Area) |
| Simple Backup Function | The CPU Unit's Simple Backup Function can be used to backup the Protocol Macro data in the Serial
Communications Unit to the CPU Unit's Memory Card. The backed-up data can be restored or compared.
(The Simple Backup Function can be used with the CJ1-H and CJ1M CPU Units only.) |
Current consumption
*3 | 280mA+x | 400mA | 360mA+x | 280mA+x | 380mA | 380mA+x |
| Weight | 160g Max. | 120g Max. | 140g Max. | 110g Max. | 110g Max. | 110g Max. |
| General specifications | Conforms to general specifications for CJ Serise. |
*1. Serial Gateway: The Serial Gateway can also be executed in protocol macro mode.
*2. No-protocol: An external interrupt task can be executed when data is received in No-protocol Mode. If the CJ2H CPU
Units with unit version 1.1 or later and CJ2M CPU Units is used, the high-speed communications instructions
(DRXDU(261) and DTXDU(262)) can also be used.
*3. The current consumption is for one Serial Communications Unit. When an NT-AL001 Link Adapter is connected to the
Serial Communications Unit, power is supplied to the Link Adapter from the Unit. A current consumption of 0.15A
must be added for each Link Adapter that is connected. In the above specifications, “x” indicates that 0.15A must be
added for each port to which an NT-AL001 Link Adapter is connected to provide the required 5-V power supply
