The Omron CJ2H-CPU68, also cataloged as the CJ2H-CPU68 Programmable Logic Controller, operates as a dedicated hardware component for high-speed logic processing and large-scale memory execution within Omron CJ2 Series automation platforms.

Technical Identifier Matrix

• Base Part Number: CJ2H-CPU68
• Series Platform: CJ2 Series (CJ2H)
• Product Classification: Central Processing Unit Module
• Internal Execution Architecture: Parallel execution hardware engine for basic and special instructions

Hardware Specifications

Backplane Bus Throughput and High-Density Memory Execution

The Omron CJ2H-CPU68 connects directly to the CJ-Series backplane bus to deliver high-velocity instruction cycles across connected Special I/O Units, CPU Bus Units, and local digital I/O modules. Featuring a dedicated logic execution hardware core, the processor maintains execution speeds down to 0.016 us min. for basic instructions and 0.048 us min. for special instructions across an expanded 400K-step program capacity.

System instruction determinism is preserved via a fixed 100 us overhead processing period. Power draw is regulated to 0.42 A on the internal 5 VDC bus line supplied directly from the CPU rack power supply. Extended force-setting/resetting capabilities across EM Area Banks 0 to 18 hex allow extensive real-time testing of expanded data registers without interruption to backplane bus velocity.

Package Contents & Ordering Information

• 1x Omron CJ2H-CPU68 Central Processing Unit
• 1x CJ1W-BAT01 Backup Lithium Battery
• 1x Serial Port Protective Cap
• 1x Hardware Installation Sheet

Field Installation Guidelines

• Panel Mounting: Secure the processor onto a standard 35 mm DIN rail or directly to a panel backplate using M4 hardware inside an IP54 enclosure. Maintain a minimum vertical spacing of 20 mm above and below the module to allow passive thermal ventilation.
• Rack Assembly: Align the module side connectors with adjacent CJ-Series power supply and expansion units. Slide top and bottom locking levers until a firm click confirms total backplane bus engagement.
• Grounding Protocol: Connect a dedicated conductor (minimum 2.0 mm sq.) from the power supply functional ground (FG) terminal to earth ground. Ensure the total ground resistance path measures under 100 ohm.
• Serial Interface Wiring: Attach RS-232C serial communication cables with maximum lengths restricted to 15 m. Isolate communication conduits from high-voltage motor or AC distribution wiring.
• Shielding Standard: Ground cable braid shields to the metallic connector housing to ensure 360-deg braid shielding against industrial high-frequency electromagnetic interference.

Frequently Asked Questions

• What current load does the CJ2H-CPU68 draw from the internal 5 VDC backplane bus?

  The module draws 0.42 A at 5 VDC from the rack power supply unit via the backplane bus connection.

• What basic instruction speed is achieved by the internal logic engine?

  Basic ladder instructions execute in a minimum processing time of 0.016 us, while special instructions process in 0.048 us min.

• What sizes of CompactFlash memory cards are compatible with the integrated memory card slot?

  The unit supports industrial CompactFlash memory cards with capacities of 128 MB, 256 MB, or 512 MB.

• What EM Area Banks are allocated for bit force-setting and resetting?

  Force-setting/resetting covers EM Area Banks 0 through 18 hex, or Banks 11 through 18 hex under automatic address allocation specifications.

• What is the maximum physical cable distance supported by the built-in serial port?

  The RS-232C serial communication port supports a maximum cable run of 15 m operating in half-duplex start-stop mode.

• How many total program steps and function block instances are supported in memory?

  The CPU provides 400K steps of user memory capacity and supports up to 2048 function block instances and 2048 definitions.

• Can the CJ2H-CPU68 module be hot-swapped while the CJ rack power supply is energized?

  No, input power to the rack power supply module must be disconnected before installing or removing the CPU unit to protect the backplane pins.

• What is the maximum ground loop resistance allowed for system earth grounding?

  The functional ground connection must maintain an electrical grounding resistance of less than 100 ohm.