{"product_id":"omron-cj1m-cpu21-sysmac-cj-series-plc-cpu-module","title":"Omron CJ1M-CPU21 SYSMAC CJ Series PLC CPU Module","description":"\u003ch3\u003eDescription\u003c\/h3\u003e\n\u003cp style=\"color: #2d3748; margin-bottom: 1rem;\"\u003eExecuting high-speed logic and integrated motion control within a compact frame, the \u003cstrong\u003eOmron CJ1M-CPU21\u003c\/strong\u003e central processing unit provides standard automation solutions for small-to-mid-sized industrial architectures. As a core component of the SYSMAC CJ Series, this CPU combines high-speed processing capabilities with versatile built-in multi-function I\/O, allowing machine builders to execute complex positioning, pulse output, and interrupt functions without requiring external co-processors or dedicated expansion modules. Designed for high reliability in tight panel configurations, its modular, backplaneless structure simplifies hardware assembly and speeds up commissioning cycles.\u003c\/p\u003e\n\n\u003ch3\u003eFeatures\u003c\/h3\u003e\n\u003cul style=\"list-style-type: square; color: #2d3748; margin-bottom: 1.5rem; padding-left: 1.5rem;\"\u003e\n  \u003cli\u003e\n\u003cstrong\u003eEfficient Program Capacity:\u003c\/strong\u003e Features a 5 Ksteps program memory alongside 32 Kwords of dedicated Data Memory (DM area) for local data logging and recipe management.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHigh-Speed Instruction Execution:\u003c\/strong\u003e Operates at an execution speed of 100 ns for basic LD instructions and 0.3 microseconds for complex MOV instructions, ensuring fast response times.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDirect Built-In I\/O Interface:\u003c\/strong\u003e Integrated with 10 inputs (including quick-response interrupt inputs and high-speed counter inputs) and 6 outputs (supporting dual 100-kHz pulse outputs and a single PWM output).\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFlexible Expansion Capacity:\u003c\/strong\u003e Supports mounting up to 10 local CJ-series I\/O and functional units directly on the CPU rack for custom configuration options.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eEmbedded Communications:\u003c\/strong\u003e Built-in peripheral port and standard RS-232C serial interface enable concurrent connections to programming terminals, HMIs, or third-party serial devices.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRemovable Storage Support:\u003c\/strong\u003e Features an integrated Compact Flash card slot for seamless program backups, data logging, and firmware maintenance.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eApplications\u003c\/h3\u003e\n\u003cul style=\"list-style-type: square; color: #2d3748; margin-bottom: 1.5rem; padding-left: 1.5rem;\"\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHigh-Speed Labeling and Packaging:\u003c\/strong\u003e Driving stepper or servo systems using built-in high-speed pulse outputs.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eConveyor and Sorting Systems:\u003c\/strong\u003e Managing photo-eye sensors and divert gates via integrated high-speed interrupts.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eAssembly and Material Handling:\u003c\/strong\u003e Running distributed automation tasks with local fieldbus masters on the same rack.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDedicated OEM Machinery:\u003c\/strong\u003e Serving as the standalone master controller in compact machine frames requiring high-density local control.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cdiv style=\"overflow-x: auto; width: 100%; margin-bottom: 1.5rem;\"\u003e\n  \u003ctable style=\"border-collapse: collapse; width: 100%; color: #2d3748; text-align: left;\"\u003e\n    \u003cthead\u003e\n      \u003ctr style=\"border-bottom: 2px solid #1a365d;\"\u003e\n        \u003cth style=\"padding: 10px; font-weight: bold;\"\u003eParameter\u003c\/th\u003e\n        \u003cth style=\"padding: 10px; font-weight: bold;\"\u003eSpecification\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eManufacturer\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eOmron\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eModel\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eCJ1M-CPU21\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eSeries\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eSYSMAC CJ1M\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eProgram Capacity\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e5 Ksteps\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eData Memory Capacity\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e32 Kwords (DM Area only)\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eLD Instruction Speed\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e100 ns\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eBuilt-in Inputs\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e10 points (including 4 interrupt\/quick-response inputs)\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eHigh-Speed Counters\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e2 channels (50-kHz phase-differential or 100-kHz single-phase)\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eBuilt-in Outputs\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e6 points (including 2 pulse outputs and 1 PWM output)\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003ePulse Output Frequency\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e100 kHz (2 channels)\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eMaximum Connectable Units\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e10 units (local CPU rack only)\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eExpansion Rack Support\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eNot supported\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eCommunication Ports\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e1x Peripheral port, 1x RS-232C port\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eInternal Power Consumption\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e0.58 A at 5 VDC\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eShipping Weight (Calculated)\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e0.35 kg\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eCountry of Origin\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eJapan\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch3\u003eConnections and Interfaces\u003c\/h3\u003e\n\u003cdiv style=\"overflow-x: auto; width: 100%; margin-bottom: 1.5rem;\"\u003e\n  \u003ctable style=\"border-collapse: collapse; width: 100%; color: #2d3748; text-align: left;\"\u003e\n    \u003cthead\u003e\n      \u003ctr style=\"border-bottom: 2px solid #1a365d;\"\u003e\n        \u003cth style=\"padding: 10px; font-weight: bold;\"\u003ePort \/ Connector\u003c\/th\u003e\n        \u003cth style=\"padding: 10px; font-weight: bold;\"\u003eInterface Type\u003c\/th\u003e\n        \u003cth style=\"padding: 10px; font-weight: bold;\"\u003ePrimary Assignment \/ Function\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003ePeripheral Port\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eCustom Omron Peripheral Connector\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eCX-Programmer software upload, download, and online monitoring\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eRS-232C Port\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eD-Sub 9-pin Female\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eModbus RTU Master\/Slave, Host Link protocol, NT Link for HMI, or serial gateway\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eBuilt-in I\/O Connector\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eMIL 40-pin Connector\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003e10 high-speed\/interrupt inputs, 6 high-speed pulse\/PWM outputs, and reference ground\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr style=\"border-bottom: 1px solid #e2e8f0;\"\u003e\n        \u003ctd style=\"padding: 10px; font-weight: bold;\"\u003eMemory Card Slot\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eCompact Flash (CF) Type I\u003c\/td\u003e\n        \u003ctd style=\"padding: 10px;\"\u003eExternal system backup, parameter auto-loading, and data collection logs\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch3\u003eEmpirical Engineering Insights\u003c\/h3\u003e\n\u003ch4\u003eAlternative Models \u0026amp; Compatibility\u003c\/h4\u003e\n\u003cp style=\"color: #2d3748; margin-bottom: 1rem;\"\u003eThe CJ1M-CPU21 is a classic of the SYSMAC family. For modern installations requiring faster communication rates or integrated EtherNet\/IP, the \u003cstrong\u003eCJ2M-CPU31\u003c\/strong\u003e acts as a physical replacement candidate, though it utilizes option boards for extra communication interfaces instead of a fixed, built-in configuration. When transferring code from the CJ1M to the CJ2M, verify that address mapping in the CIO and DM areas matches, as some built-in I\/O registers have different default locations.\u003c\/p\u003e\n\n\u003ch4\u003eApplication Pitfalls \u0026amp; Engineering Notes\u003c\/h4\u003e\n\u003cp style=\"color: #2d3748; margin-bottom: 1rem;\"\u003eBecause this CPU does not support expansion racks (it lacks the internal bus transmitters required for expansion cables), you are strictly limited to the 10 slots on the local CPU rack. Adding high-current modules, such as multiple analog input cards or fieldbus masters, can quickly overwhelm standard CPU-rack power supplies like the CJ1W-PA201. Always calculate the total 5V\/24V power draw during the design phase to prevent erratic CPU drops or diagnostic watch-dog timer errors.\u003c\/p\u003e\n\n\u003ch4\u003eCommissioning \u0026amp; Wiring Tips\u003c\/h4\u003e\n\u003cp style=\"color: #2d3748; margin-bottom: 1rem;\"\u003eTo guarantee clean execution of the 100-kHz pulse outputs and 50-kHz high-speed counters, shield all MIL 40-pin connector cabling. Ground the shield at the cabinet ground plate, and never route these signal lines parallel to high-voltage lines or AC motor leads to avoid induction noise that can lead to position drifting.\u003c\/p\u003e\n\n\u003ch3\u003eInstallation Guidelines\u003c\/h3\u003e\n\u003cdiv style=\"background-color: #fff5f5; border-left: 4px solid #c53030; padding: 1rem; margin-bottom: 1.5rem; border-radius: 4px;\"\u003e\n  \u003cp style=\"color: #9b2c2c; font-weight: bold; margin: 0 0 0.5rem 0;\"\u003eCRITICAL WARNING\u003c\/p\u003e\n  \u003cp style=\"color: #9b2c2c; margin: 0; font-size: 0.95rem;\"\u003eAlways isolate all electrical power systems before attaching or detaching any module on the CJ-series rack. Removing or adding modules while the backplane is energized will trigger severe backplane communications faults, can instantly corrupt volatile data memory, and risks destroying the integrated CMOS drive circuitry within the CPU.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003cdiv style=\"display: flex; flex-direction: column; gap: 1rem; margin-bottom: 1.5rem;\"\u003e\n  \u003cdiv style=\"display: flex; align-items: flex-start; gap: 1rem;\"\u003e\n    \u003cdiv style=\"background-color: #2b6cb0; color: #ffffff; width: 28px; height: 28px; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-weight: bold; flex-shrink: 0;\"\u003e1\u003c\/div\u003e\n    \u003cdiv style=\"color: #2d3748;\"\u003e\n      \u003cstrong\u003eBackplane DIN Rail Mounting:\u003c\/strong\u003e Slide the CJ1M-CPU21 onto the DIN rail from the front. Secure the module to the backplane by hooking the top catch and pushing down until the bottom lock clicks firmly in place.\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n  \u003cdiv style=\"display: flex; align-items: flex-start; gap: 1rem;\"\u003e\n    \u003cdiv style=\"background-color: #2b6cb0; color: #ffffff; width: 28px; height: 28px; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-weight: bold; flex-shrink: 0;\"\u003e2\u003c\/div\u003e\n    \u003cdiv style=\"color: #2d3748;\"\u003e\n      \u003cstrong\u003eI\/O Terminal Wiring:\u003c\/strong\u003e Attach the 40-pin MIL connector cable securely to the front of the CPU module, ensuring that the locking tabs engage on both sides to prevent contact issues during vibration.\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n  \u003cdiv style=\"display: flex; align-items: flex-start; gap: 1rem;\"\u003e\n    \u003cdiv style=\"background-color: #2b6cb0; color: #ffffff; width: 28px; height: 28px; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-weight: bold; flex-shrink: 0;\"\u003e3\u003c\/div\u003e\n    \u003cdiv style=\"color: #2d3748;\"\u003e\n      \u003cstrong\u003eBattery and CF Card Check:\u003c\/strong\u003e Open the front compartment door, ensure the backup battery plug is firmly connected to its receptacle, and snap the Compact Flash card into the guide slots if loading parameters.\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n  \u003cdiv style=\"display: flex; align-items: flex-start; gap: 1rem;\"\u003e\n    \u003cdiv style=\"background-color: #2b6cb0; color: #ffffff; width: 28px; height: 28px; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-weight: bold; flex-shrink: 0;\"\u003e4\u003c\/div\u003e\n    \u003cdiv style=\"color: #2d3748;\"\u003e\n      \u003cstrong\u003eSystem Grounding:\u003c\/strong\u003e Connect a low-impedance ground conductor (minimum 2 mm squared) to the functional ground terminal on the adjacent power supply unit to minimize high-frequency electromagnetic interference.\n    \u003c\/div\u003e\n  \u003c\/div\u003e\n\u003c\/div\u003e","brand":"Omron","offers":[{"title":"Default Title","offer_id":53077920940395,"sku":"CJ1MCPU21","price":100.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0953\/3227\/0443\/files\/CJ1MCPU21-cuojal2yhsd.png?v=1775733485","url":"https:\/\/www.plcprotech.com\/id\/products\/omron-cj1m-cpu21-sysmac-cj-series-plc-cpu-module","provider":"PLC ProTech Ltd.","version":"1.0","type":"link"}