{"product_id":"1747-l20c-allen-bradley-slc-500-processor-unit","title":"1747-L20C Allen-Bradley SLC 500 Processor Unit","description":"\u003cp\u003eConfigured for discrete logic execution and input\/output control within fixed-configuration architecture, the \u003cstrong\u003eAllen-Bradley 1747-L20C\u003c\/strong\u003e (\u003cstrong\u003e1747L20C\u003c\/strong\u003e Processor Unit) provides direct physical\/electrical execution across onboard digital channels and DH-485 network loops.\u003c\/p\u003e\n\u003ch3\u003eModel Suffix Nomenclature Analysis\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e1747-L20C: Base catalog designation representing a fixed hardware style controller containing 1 K words of memory and AC line power circuitry.\u003c\/li\u003e\n\u003cli\u003e1747L20C: Alternative spare parts tracking nomenclature referencing the identical physical processor hardware without embedded license modifications.\u003c\/li\u003e\n\u003cli\u003eFixed Hardware Style: Indicates non-modular backplane layout where processor, power supply, and fixed I\/O terminals reside on a single integrated printed circuit assembly.\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\u003e1747-L20C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eAllen-Bradley\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOrigin\u003c\/td\u003e\n\u003ctd\u003eUSA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e1.8 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eShipping Dimensions\u003c\/td\u003e\n\u003ctd\u003e17.8 x 15.2 x 15.2 cm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Temp\u003c\/td\u003e\n\u003ctd\u003e0 to 60 deg C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Consumption\u003c\/td\u003e\n\u003ctd\u003e85-265 VAC, 47-63 Hz\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDigital Inputs\u003c\/td\u003e\n\u003ctd\u003e12 channels, 24 VDC Sink\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDigital Outputs\u003c\/td\u003e\n\u003ctd\u003e8 channels, AC\/DC Relay\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMemory Capacity\u003c\/td\u003e\n\u003ctd\u003e1 K words\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003ch3\u003eController Logic Architecture and I\/O Scaling\u003c\/h3\u003e\n\u003cp\u003eThe processor handles real-time machine automation by executing user ladder logic programs stored within 1 K words of memory. I\/O density scaling is fixed to 12 sinking 24 VDC inputs and 8 relay outputs, operating synchronously with firmware routines. DH-485 communication ports facilitate peer-to-peer data exchange and programming terminal connectivity across industrial networks.\u003c\/p\u003e\n\u003ch3\u003ePackage Ordering Information\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e1 x Allen-Bradley 1747-L20C fixed hardware controller unit\u003c\/li\u003e\n\u003cli\u003e1 x Integrated terminal block barrier strip assembly\u003c\/li\u003e\n\u003cli\u003e1 x Factory configuration data sheet and jumper documentation\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003ePhysical Installation and Wiring Guidelines\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eEnclosure Mounting: Secure the controller unit to a flat vertical panel using standard mounting holes, ensuring adequate surrounding air clearance for thermal dissipation.\u003c\/li\u003e\n\u003cli\u003eAC Power Supply Wiring: Connect line power across the designated 120-240 VAC terminals, ensuring an inline fuse protection limit of 1.25 A is maintained.\u003c\/li\u003e\n\u003cli\u003eDigital Input Routing: Route 24 VDC sink input wiring separately from high-voltage AC power cables to prevent electromagnetic noise coupling.\u003c\/li\u003e\n\u003cli\u003eRelay Output Isolation: Adhere strictly to maximum contact rating limits when driving inductive loads, applying suppression diodes or RC snubbers across output terminals.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eDoes this processor support hot-insertion and removal under power?\n\u003cul\u003e\n\u003cli\u003eNo, the 1747-L20C features a fixed hardware architecture and must be completely de-energized before performing any wiring or mechanical maintenance.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003eWhat is the native communication protocol used by this controller?\n\u003cul\u003e\n\u003cli\u003eThe unit utilizes the DH-485 proprietary network protocol for programming downloads and peer-to-peer data transmission.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003eCan additional I\/O modules be expanded onto this fixed controller?\n\u003cul\u003e\n\u003cli\u003eNo, fixed hardware style controllers possess a non-expandable base architecture restricted strictly to their onboard 12 inputs and 8 outputs.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003eWhat type of input signal configuration do the digital terminals accept?\n\u003cul\u003e\n\u003cli\u003eThe 12 digital input channels are configured specifically for 24 VDC sinking device connections.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003eWhat is the maximum line power voltage tolerance for the power supply?\n\u003cul\u003e\n\u003cli\u003eThe integrated power supply accepts an operational voltage range spanning from 85 to 265 VAC at 47 to 63 Hz frequencies.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003eHow is user program memory retained when power is removed?\n\u003cul\u003e\n\u003cli\u003eUser programs are stored in non-volatile memory or backed up via internal battery configurations to prevent data loss during power cycles.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003eWhat current protection is built into the AC power line input?\n\u003cul\u003e\n\u003cli\u003eThe unit incorporates a power supply fuse protection rating specified at 1.25 A to safeguard internal power circuits.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003eIs the controller hardware still actively manufactured by the vendor?\n\u003cul\u003e\n\u003cli\u003eNo, this unit was officially discontinued by the manufacturer on September 30, 2009, and requires legacy support considerations.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Allen-Bradley","offers":[{"title":"Default Title","offer_id":46066409537709,"sku":"1747-L20C","price":88.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0733\/1613\/9181\/files\/1747-L20C_1.jpg?v=1785927990","url":"https:\/\/www.maxwellplc.com\/ru\/products\/1747-l20c-allen-bradley-slc-500-processor-unit","provider":"Maxwell PLC Ltd","version":"1.0","type":"link"}