{"product_id":"allen-bradley-1756-l55-controllogix-processor-module","title":"Allen-Bradley 1756-L55 ControlLogix Processor Module","description":"\u003cp\u003eThe \u003cstrong\u003eAllen-Bradley 1756-L55\u003c\/strong\u003e, also cataloged as the \u003cstrong\u003e1756-L55\u003c\/strong\u003e Processor Module, operates as a dedicated hardware component for central logic processing within ControlLogix chassis platforms. The base unit features no integrated user memory onboard, requiring the installation of an optional 1756-Mxx series nonvolatile memory board to store application routines and system tag databases. The processor executes multi-tasking control routines, managing real-time cyclic I\/O polling and deterministic data transfer across the chassis backplane without relying on external coprocessor assemblies.\u003c\/p\u003e\n\u003ch3\u003eSuffix Breakdown \u0026amp; Model Matrix\u003c\/h3\u003e\n\u003cfigure class=\"table\"\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003e\u003cstrong\u003eBase Model\u003c\/strong\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cstrong\u003eMemory Board Extension\u003c\/strong\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cstrong\u003eCombined Catalog Number\u003c\/strong\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cstrong\u003eTotal User Memory\u003c\/strong\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e1756-L55\u003c\/td\u003e\n\u003ctd\u003eNone\u003c\/td\u003e\n\u003ctd\u003e1756-L55\u003c\/td\u003e\n\u003ctd\u003eNo User Memory\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e1756-L55\u003c\/td\u003e\n\u003ctd\u003e1756-M12\u003c\/td\u003e\n\u003ctd\u003e1756-L55M12\u003c\/td\u003e\n\u003ctd\u003e1.5 MB\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e1756-L55\u003c\/td\u003e\n\u003ctd\u003e1756-M13\u003c\/td\u003e\n\u003ctd\u003e1756-L55M13\u003c\/td\u003e\n\u003ctd\u003e1.5 MB\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e1756-L55\u003c\/td\u003e\n\u003ctd\u003e1756-M14\u003c\/td\u003e\n\u003ctd\u003e1756-L55M14\u003c\/td\u003e\n\u003ctd\u003e3.5 MB\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e1756-L55\u003c\/td\u003e\n\u003ctd\u003e1756-M24\u003c\/td\u003e\n\u003ctd\u003e1756-L55M24\u003c\/td\u003e\n\u003ctd\u003e3.5 MB\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\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\u003e1756-L55\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eAllen-Bradley \/ Rockwell Automation\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\u003e0.75 lbs (0.34 kg)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003eControlLogix Single-Slot Standard Module\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\u003e4.5 W (Backplane dependent)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCPU Architecture\u003c\/td\u003e\n\u003ctd\u003eLogix5555 Controller Series\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUser Memory\u003c\/td\u003e\n\u003ctd\u003eNo User Memory (Requires 1756-Mxx expansion board)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCurrent Draw\u003c\/td\u003e\n\u003ctd\u003e6.31 mA at 5.1 VDC, 14 mA at 24 VDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMounting Configuration\u003c\/td\u003e\n\u003ctd\u003eChassis Mount (1756 ControlLogix I\/O Chassis)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003ch3\u003eControlLogix Deterministic Networks \u0026amp; Firmware Synchronization\u003c\/h3\u003e\n\u003cp\u003eThe module communicates over the local ControlLogix backplane using EtherNet\/IP deterministic networks and CIP interface logic. Backplane bus communication velocity guarantees deterministic, high-speed data exchanges between the CPU card and local or remote I\/O chassis. Firmware flash compatibility via RSLogix 5000 \/ Studio 5000 enables non-destructive system updates, ensuring firmware synchronization across chassis expansion slots without physical alterations to module memory boards.\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003eQ: Can the 1756-L55 base processor execute application programs without a 1756-Mxx memory expansion board?\u003c\/p\u003e\n\u003cp\u003eA: No, the 1756-L55 base unit contains no onboard user memory. It requires a compatible 1756-Mxx expansion card (such as 1756-M12, 1756-M13, 1756-M14, or 1756-M24) to store program logic and system tag configurations.\u003c\/p\u003e\n\u003cp\u003eQ: Does the 1756-L55 processor support Removal and Insertion Under Power (RIUP)?\u003c\/p\u003e\n\u003cp\u003eA: Yes, the 1756-L55 supports Removal and Insertion Under Power (RIUP) within a powered ControlLogix rack. However, removing an active processor immediately stops controller task execution and transitions connected field output modules into their configured fault states.\u003c\/p\u003e\n\u003ch3\u003eField Installation Guidelines\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eEnsure backplane chassis grounding strictly complies with IEEE 1100 standards by establishing a direct low-impedance connection between the rack ground lug and enclosure star ground point.\u003c\/li\u003e\n\u003cli\u003eEnsure any 1756-Mxx memory expansion board is fully seated and mechanically locked onto the 1756-L55 main board prior to inserting the processor into the chassis slot.\u003c\/li\u003e\n\u003cli\u003eAlign the circuit board edges with top and bottom chassis guides, sliding the controller unit firmly into the chassis slot until both upper and lower latches click into place.\u003c\/li\u003e\n\u003cli\u003eMaintain a minimum vertical clearance distance of 50 mm (2 inches) above and below the ControlLogix chassis frame to facilitate thermal convection across module cooling vents.\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Allen-Bradley","offers":[{"title":"Default Title","offer_id":48786283528382,"sku":"1756-L55","price":99.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0725\/1145\/5422\/files\/1756-L55_61ec06d5-ec5a-48c3-8c06-22047b4219f8.png?v=1787710377","url":"https:\/\/www.autooiltech.com\/products\/allen-bradley-1756-l55-controllogix-processor-module","provider":"AutoOilTech Limited","version":"1.0","type":"link"}