{"product_id":"omron-cj1w-scu31-v1-serial-communications-unit-cj-series","title":"Omron CJ1W-SCU31-V1 Serial Communications Unit CJ Series","description":"\u003cp\u003eThe \u003cstrong\u003eOmron CJ1W-SCU31-V1\u003c\/strong\u003e, also cataloged as the \u003cstrong\u003eCJ1W-SCU31-V1\u003c\/strong\u003e Serial Communications Unit, operates as a dedicated hardware component for multi-protocol serial communication execution within Omron CJ-series PLC networks.\u003c\/p\u003e\n\u003ch3\u003eTechnical Identifier Matrix\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBase Part Number:\u003c\/strong\u003e CJ1W-SCU31-V1\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Omron\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eClassification:\u003c\/strong\u003e CPU Bus Unit\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRevision Identifier:\u003c\/strong\u003e Unit Ver. 1.2 \/ Unit Ver. 1.3\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSerial Ports:\u003c\/strong\u003e Port 1 (RS-422A\/485), Port 2 (RS-422A\/485)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eHardware Specifications\u003c\/h3\u003e\n\u003cfigure class=\"table\"\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003e\u003cstrong\u003eParameter\u003c\/strong\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cstrong\u003eSpecification\u003c\/strong\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel\u003c\/td\u003e\n\u003ctd\u003eCJ1W-SCU31-V1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eOmron\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOrigin\u003c\/td\u003e\n\u003ctd\u003eJapan\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.11 kg Max.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003e3.1 cm x 6.5 cm x 9.0 cm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eShipping Dimensions\u003c\/td\u003e\n\u003ctd\u003e15.0 cm x 10.0 cm x 5.0 cm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Temp\u003c\/td\u003e\n\u003ctd\u003e0 to 55 deg C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Consumption\u003c\/td\u003e\n\u003ctd\u003e1.90 W (380 mA at 5 VDC)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCurrent Consumption\u003c\/td\u003e\n\u003ctd\u003e380 mA Max.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePort 1 Interface\u003c\/td\u003e\n\u003ctd\u003eRS-422A\/485\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePort 2 Interface\u003c\/td\u003e\n\u003ctd\u003eRS-422A\/485\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePort 1 Protocols\u003c\/td\u003e\n\u003ctd\u003eHost Link, Protocol Macro, NT Link, Loopback Test\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePort 2 Protocols\u003c\/td\u003e\n\u003ctd\u003eHost Link, Protocol Macro, NT Link, Loopback Test, Serial Gateway, No-protocol, 1:1 Host Link, Modbus-RTU Slave (Ver. 1.3+)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMountable Units Count\u003c\/td\u003e\n\u003ctd\u003eUp to 16 Units per CPU Rack \/ Expansion Rack\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCIO Area Allocation\u003c\/td\u003e\n\u003ctd\u003e25 words (software switches and status refresh)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDM Area Allocation\u003c\/td\u003e\n\u003ctd\u003e20 words total (10 words per serial port)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSimple Backup Function\u003c\/td\u003e\n\u003ctd\u003eCompatible with CJ1-H and CJ1M CPU Units\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003ch3\u003eBackplane Bus Velocity \u0026amp; Firmware Compatibility\u003c\/h3\u003e\n\u003cp\u003eThe \u003cstrong\u003eOmron CJ1W-SCU31-V1\u003c\/strong\u003e interfaces directly with the CJ-series high-speed backplane bus, operating as a CPU Bus Unit to achieve cyclic data exchange across 25 allocated CIO words and 20 DM words. CPU refresh timing transfers status flags and software switches constantly without interrupting ladder execution cycles. Runtime configuration shifts are executed via the ladder instruction STUP (237) or by triggering the Port Settings Changing Flag in the Auxiliary Area.\u003c\/p\u003e\n\u003cp\u003eFirmware revisions expand interface routing capability without hardware retrofits. Unit Version 1.2 introduces the integrated Serial Gateway engine, which automatically converts incoming FINS commands over the backplane bus into serial protocol frames (including protocol macro execution). Unit Version 1.3 adds native Modbus-RTU slave mode to Port 2, enabling direct connectivity to standard industrial master devices without custom ladder frame parsing.\u003c\/p\u003e\n\u003ch3\u003ePackage Contents \u0026amp; Ordering Information\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e1x Omron CJ1W-SCU31-V1 Serial Communications Unit\u003c\/li\u003e\n\u003cli\u003e2x Terminal Block Connectors (RS-422A\/485)\u003c\/li\u003e\n\u003cli\u003e1x Hardware Installation Sheet\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eField Installation Guidelines\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eRack Mounting:\u003c\/strong\u003e Secure the module onto the CJ-series CPU Rack or Expansion Rack DIN rail until the upper and lower locking mechanisms engage. No slot location restrictions apply within the 16-unit total CPU Bus Unit allocation.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRS-422A\/485 Wiring:\u003c\/strong\u003e Utilize twisted-pair shielded cable for differential signaling on Port 1 and Port 2. Maintain uniform polarity across all network nodes.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShield Grounding:\u003c\/strong\u003e Connect cable shielding to the functional ground (FG) terminal using a 360-deg braid clamp at a single grounding node to suppress high-frequency electro-magnetic interference.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBus Termination:\u003c\/strong\u003e Enable the built-in terminating resistance via the DIP switch on the front panel for units positioned at the physical ends of an RS-422A\/485 transmission line.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003eWhat is the maximum backplane current draw for the CJ1W-SCU31-V1?\u003c\/p\u003e\n\u003cp\u003eThe unit draws a maximum current of 380 mA at 5 VDC directly from the CJ-series CPU backplane bus power supply.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eHow many CJ1W-SCU31-V1 units can be installed on a single CPU Rack?\u003c\/p\u003e\n\u003cp\u003eUp to 16 CPU Bus Units, including all CJ1W-SCU31-V1 modules, can be mounted on a single CPU Rack or Expansion Rack.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eWhich instruction forces a reload of the serial port setting words from the DM area?\u003c\/p\u003e\n\u003cp\u003eExecuting the ladder instruction STUP (237) forces an immediate reload of the 10 DM configuration words allocated to each serial port.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eIs hot-swapping supported for the CJ1W-SCU31-V1 module on a CJ-series rack?\u003c\/p\u003e\n\u003cp\u003eNo, power to the CPU Rack and Expansion Racks must be completely turned OFF before inserting or removing the CJ1W-SCU31-V1 unit.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eDoes the CJ1W-SCU31-V1 support Modbus-RTU slave mode on both ports?\u003c\/p\u003e\n\u003cp\u003eModbus-RTU slave mode is supported on Port 2 only, requiring Unit Version 1.3 or later firmware.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eHow does the Simple Backup Function interact with the CJ1W-SCU31-V1 protocol macro data?\u003c\/p\u003e\n\u003cp\u003eThe Simple Backup Function backs up internal Protocol Macro data to a Memory Card installed in CJ1-H or CJ1M CPU Units for restoration or comparison.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eWhat memory areas are allocated to the CJ1W-SCU31-V1 in the CPU Unit?\u003c\/p\u003e\n\u003cp\u003eThe module receives 25 words in the CPU Bus Unit CIO Area and 20 words in the CPU Bus Unit DM Area (10 words per port).\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eWhat grounding practice is required for long-distance RS-485 serial runs?\u003c\/p\u003e\n\u003cp\u003eField cabling requires 360-deg braid shielding connected to a low-impedance protective earth terminal to eliminate ground potential loops and signal noise.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Omron","offers":[{"title":"Default Title","offer_id":47306629808301,"sku":"CJ1W-SCU31-V1","price":173.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0733\/1613\/9181\/files\/CJ1W-SCU31-V1_2.jpg?v=1788157066","url":"https:\/\/www.maxwellplc.com\/ga\/products\/omron-cj1w-scu31-v1-serial-communications-unit-cj-series","provider":"Maxwell PLC Ltd","version":"1.0","type":"link"}