{"product_id":"1747-l542-allen-bradley-slc-500-slc-5-04-cpu-module-32k","title":"1747-L542 Allen-Bradley SLC 500 SLC 5\/04 CPU Module 32K","description":"\u003ch3\u003e\u003cstrong\u003eOverview\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe \u003cstrong style=\"color: #0056b3;\"\u003eAllen-Bradley 1747-L542\u003c\/strong\u003e serves as a high-performance central processing unit within the \u003cstrong style=\"color: #0056b3;\"\u003eSLC 500\u003c\/strong\u003e modular hardware family. Engineered by \u003cstrong style=\"color: #0056b3;\"\u003eRockwell Automation\u003c\/strong\u003e, this \u003cstrong style=\"color: #0056b3;\"\u003eSLC 5\/04 Processor\u003c\/strong\u003e delivers fast execution speeds and reliable control for complex industrial automation systems. The controller manages extensive I\/O configurations while providing native dual-protocol network integration.\u003c\/p\u003e\n\u003cp\u003eEquipped with 32KB of battery-backed user memory, the \u003cstrong style=\"color: #0056b3;\"\u003e1747-L542\u003c\/strong\u003e handles up to 4,096 discrete inputs and 4,096 discrete outputs effortlessly. Built-in Data Highway Plus (DH+) and RS-232 communication ports allow direct connection to HMI displays, SCADA packages, and peer-to-peer PLC networks without requiring extra communication modules.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eTechnical Specifications\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe engineering specifications below group performance metrics logically across operational categories using MECE principles.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e \u003cstrong style=\"color: #0056b3;\"\u003eAllen-Bradley\u003c\/strong\u003e \/ \u003cstrong style=\"color: #0056b3;\"\u003eRockwell Automation\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCatalog Number:\u003c\/strong\u003e \u003cstrong style=\"color: #0056b3;\"\u003e1747-L542\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Series:\u003c\/strong\u003e \u003cstrong style=\"color: #0056b3;\"\u003eSLC 500\u003c\/strong\u003e (\u003cstrong style=\"color: #0056b3;\"\u003eSLC 5\/04\u003c\/strong\u003e Platform)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProcessor Memory:\u003c\/strong\u003e 32KB Words (28K program words, 4K data words)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDiscrete I\/O Capacity:\u003c\/strong\u003e 4096 Inputs \/ 4096 Outputs\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAnalog I\/O Support:\u003c\/strong\u003e Up to 480 local analog points\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMax Expansion Capacity:\u003c\/strong\u003e 3 local chassis \/ 30 total module slots\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProgram Scan Time:\u003c\/strong\u003e 0.9 ms per Kword (typical)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eI\/O Scan Time:\u003c\/strong\u003e 0.225 ms\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBit Execution Speed:\u003c\/strong\u003e 0.37 microseconds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIntegrated Communication Ports:\u003c\/strong\u003e DH+ (Data Highway Plus) and RS-232\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOperating Temperature:\u003c\/strong\u003e 0 to 60 °C (32 to 140 °F)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStorage Temperature:\u003c\/strong\u003e -40 to 85 °C (-40 to 185 °F)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAmbient Relative Humidity:\u003c\/strong\u003e 5% to 95% non-condensing\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVibration Tolerance:\u003c\/strong\u003e 2.5G at 57 to 2000 Hz\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOperating Shock Rating:\u003c\/strong\u003e 30G peak\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eElectromagnetic Immunity:\u003c\/strong\u003e Industrial noise rejection via backplane shielding\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMemory Backup Type:\u003c\/strong\u003e Battery-backed RAM with optional 1747-M13 Flash EPROM\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBackplane Current Draw:\u003c\/strong\u003e 1.0A at 5V DC \/ 175mA at 24V DC\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePower Hold-up Time:\u003c\/strong\u003e 20 milliseconds to 3 seconds following power loss\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cstrong\u003eInstallation Guide\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eFollow these standard engineering procedures to ensure safe installation of your controller.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eTurn off power to the system chassis before inserting or removing the unit.\u003c\/li\u003e\n\u003cli\u003eInsert the \u003cstrong style=\"color: #0056b3;\"\u003e1747-L542\u003c\/strong\u003e strictly into Slot 0 (leftmost position) of any \u003cstrong style=\"color: #0056b3;\"\u003eSLC 500\u003c\/strong\u003e chassis.\u003c\/li\u003e\n\u003cli\u003eAlign the circuit card with the chassis guide rails inside chassis like the 1746-A7 or 1746-A10.\u003c\/li\u003e\n\u003cli\u003ePress the module firmly into the backplane connector until top and bottom latches secure it.\u003c\/li\u003e\n\u003cli\u003eConnect the 1747-BA lithium battery module to preserve user program memory during main power shutdown.\u003c\/li\u003e\n\u003cli\u003eConnect communication cables to the DH+ or 9-pin RS-232 ports before energizing the power supply.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cstrong\u003eDiagnostics \u0026amp; Maintenance Convenience\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe front panel includes diagnostic LEDs that provide immediate status feedback during operation. Maintenance engineers can quickly assess processor health without connecting a computer.\u003c\/p\u003e\n\u003cp\u003eClear status indicators display system states for RUN, CPU FAULT, FORCED I\/O, BATTERY LOW, DH+, and RS-232. A three-position key switch lets operators easily select RUN, PROG, or REM mode for safe program modifications on site.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eSystem Compatibility\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThe \u003cstrong style=\"color: #0056b3;\"\u003e1747-L542\u003c\/strong\u003e processor maintains broad hardware and software compatibility across legacy and modern platforms.\u003c\/p\u003e\n\u003cp\u003eIt mounts in standard 1746 chassis including 1746-A2, 1746-A7, 1746-A10, and 1746-A13 models. The integrated DH+ port supports pass-through messaging to ControlLogix, CompactLogix, and PLC-5 controllers across multi-tier networks.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eCertification \u0026amp; Compliance\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eThis controller meets global industrial control standards for safety and operational reliability.\u003c\/p\u003e\n\u003cp\u003eIt carries UL approval, CE mark compliance, and C-Tick certification for industrial electromagnetic compatibility. Universal industry codes include UPC 10662468417454 and UNSPSC 32151705.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eTypical Application Scenarios\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eEngineers deploy the \u003cstrong style=\"color: #0056b3;\"\u003e1747-L542\u003c\/strong\u003e in medium to large industrial automation systems requiring fast network execution.\u003c\/p\u003e\n\u003cp\u003eCommon applications include automotive assembly lines, municipal water treatment facilities, material handling systems, and packaging machinery. Its high-speed DH+ networking capability makes it ideal for distributed control architectures with remote I\/O nodes.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003ePackaging Details \u0026amp; 12-Month Warranty\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eEach unit ships in protective static-shielding packaging inside a heavy-duty industrial carton. The box contains the \u003cstrong style=\"color: #0056b3;\"\u003e1747-L542\u003c\/strong\u003e module, a factory key, and an installation instruction sheet.\u003c\/p\u003e\n\u003cp\u003eWe provide a full 12-month warranty covering operational performance and hardware function. Orders process rapidly with dispatch within 24 to 48 hours via express carriers like FedEx, UPS, or DHL.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eGlobal PLC Spare HUB's Insight \u0026amp; Field Experience\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eOur automation specialists routinely evaluate legacy control hardware in live field environments. The \u003cstrong style=\"color: #0056b3;\"\u003e1747-L542\u003c\/strong\u003e remains one of the most resilient workhorses in industrial control history due to its robust DH+ communication throughput.\u003c\/p\u003e\n\u003cp\u003eIn a recent field installation at a bottling plant, an engineer reported recurring CPU FAULT errors after a facility power outage. Our team identified that the onboard 1747-BA battery had drained below its operational voltage threshold. Installing a fresh battery alongside a 1747-M13 EEPROM backup module saved the client days of production downtime by automatically restoring logic during unexpected outages. Always pair high-memory \u003cstrong style=\"color: #0056b3;\"\u003eSLC 5\/04\u003c\/strong\u003e controllers with non-volatile EEPROM modules for complete operational security.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eBuying Guide \u0026amp; Selection Advice\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003eSelecting the correct \u003cstrong style=\"color: #0056b3;\"\u003eSLC 500\u003c\/strong\u003e processor depends on your network infrastructure and system memory needs.\u003c\/p\u003e\n\u003cp\u003eIf your application relies on Data Highway Plus (DH+) networks, choose the \u003cstrong style=\"color: #0056b3;\"\u003eSLC 5\/04\u003c\/strong\u003e series like the \u003cstrong style=\"color: #0056b3;\"\u003e1747-L542\u003c\/strong\u003e. If your architecture uses DH-485 instead, consider the SLC 5\/03 series such as the 1747-L532. Ensure your program memory fits within 32KB words before selecting this unit over higher-capacity processors.\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003eFrequently Asked Questions (FAQ)\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the main difference between an SLC 5\/03 and an SLC 5\/04 processor?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe SLC 5\/03 processor utilizes a DH-485 network port, whereas the SLC 5\/04 processor like the \u003cstrong style=\"color: #0056b3;\"\u003e1747-L542\u003c\/strong\u003e features a high-speed Data Highway Plus (DH+) network interface.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow do I resolve a red BATT LED on the front panel?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eReplace the 1747-BA lithium battery while system power remains turned on to prevent losing program data stored in volatile RAM.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I install the 1747-L542 in any slot of an SLC chassis?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNo, you must install the processor exclusively into Slot 0 of the local chassis.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat happens if the main power fails and the battery is dead?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe processor loses user program logic stored in RAM unless a non-volatile memory module like the 1747-M13 Flash EPROM is present.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow fast does order dispatch take after placing an order?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eOrders ship within 24 to 48 hours via fast express services including FedEx, UPS, or DHL.\u003c\/p\u003e","brand":"Allen-Bradley","offers":[{"title":"Default Title","offer_id":45014018752694,"sku":"1747-L542","price":164.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0722\/7863\/8774\/files\/1747-L542_473e7ad4-5157-4577-99df-c18716ea3157.jpg?v=1784701750","url":"https:\/\/www.plcsparehub.com\/products\/1747-l542-allen-bradley-slc-500-slc-5-04-cpu-module-32k","provider":"Global PLC Spare Hub","version":"1.0","type":"link"}