The Omron CJ1M-CPU12, also cataloged as the CJ1M-CPU12 CPU Unit, operates as a dedicated hardware component for centralized programmable logic execution and system sequencing within Omron CJ Series automation platforms. Configured for real-time control across local rack architectures, this processor executes high-speed instructions, manages system interrupts, and coordinates data transfer across up to 10 total connected modules via dedicated serial and peripheral interface ports.

Technical Identifier Matrix

Hardware Specifications

PLC Backplane Bus Velocity and Serial Determinism

The CJ1M-CPU12 provides precise backplane execution velocity with a basic LD instruction execution time of 100 ns (0.10 microseconds) and a MOV instruction execution time of 0.30 microseconds. System scan processing maintains a low overhead latency of 0.5 ms. The CJ1M-CPU12 supports local rack connectivity for up to 10 modules and manages an I/O capacity of up to 320 physical points. Serial communications via the built-in RS-232C port and peripheral port support Host Link, no-protocol, and FINS serial framing. An integrated CompactFlash slot facilitates non-volatile backup and restore operations for programs, setup parameters, and DM data memory contents without continuous battery reliance.

Package Contents & Ordering Information

• 1x Omron CJ1M-CPU12 CPU Unit

• 1x End Cover (CJ1W-TER01 required for backplane termination)

• 1x Quick Reference Manual Document

Field Installation Guidelines

• Mounting Configuration: Direct-mount the CPU unit onto a standard 35 mm DIN rail. Ensure the module is locked adjacent to the power supply unit on the leftmost position of the CPU rack.

• Expansion Restrictions: Expansion racks are not supported on this model. Hardware expansion is limited to a maximum of 10 units mounted directly on the local CPU rack.

• Backplane Bus Termination: Secure a CJ1W-TER01 End Cover to the rightmost unit on the local CPU rack to close the backplane communication circuit.

• Serial Cable Shielding: For RS-232C communication lines, use shielded twisted-pair cabling. Connect the shield braid to the shell of the D-sub connector and ground the frame ground (FG) terminal to an earth point with resistance under 100 ohms.

Frequently Asked Questions

• What is the maximum physical I/O capacity supported by the CJ1M-CPU12?

  The CPU supports up to 320 physical I/O points distributed across a maximum of 10 connectable I/O units on the CPU rack.

• How many expansion racks can be connected to the CJ1M-CPU12?

  Expansion racks are not supported on the CJ1M-CPU12. System configuration is strictly limited to 10 local rack units.

• What basic instruction execution speeds does this model achieve?

  The module executes basic LD (Load) instructions in 100 ns (0.10 microseconds) and MOV instructions in 0.30 microseconds.

• What built-in serial communication interface ports are provided?

  The CPU includes 1 built-in RS-232C port (D-sub 9-pin) and 1 dedicated peripheral port for programming and host communications.

• What memory card type is supported for external program storage?

  The CPU features an integrated card slot that accepts standard CompactFlash memory cards for data logging, parameter loading, and program storage.

• What is the user program capacity and data memory size?

  The CJ1M-CPU12 provides 10K steps of user program capacity and 32K words of Data Memory (DM). Extended Memory (EM) is not supported.

• Is hot-swapping allowed on the CJ1M-CPU12 backplane?

  No, main power to the rack power supply unit must be turned off before inserting or removing any CPU or I/O modules on the backplane.

• Why is the CJ1W-TER01 End Cover required?

  The CJ1W-TER01 terminates the backplane bus logic circuit. The CPU will flag a bus error and fail to execute logic if the end cover is absent.