{"product_id":"allen-bradley-1756-l55-controllogix-controller","title":"Allen-Bradley 1756-L55 ControlLogix Controller","description":"\u003cdiv\u003e\u003cp\u003eThe Allen-Bradley 1756-L55 ControlLogix Controller is a high-performance Logix5555 CPU designed for Rockwell Automation's ControlLogix systems, intended to govern large, deterministic I\/O and process control within a 1756 backplane chassis. The 1756-L55M14 variant includes 1.5 MB of nonvolatile user memory for programs and data, supporting larger control projects while preserving data across power cycles. Catalog numbers in this family include 1756-L55, 1756-L55M12, 1756-L55M13, 1756-L55M14, and 1756-L55M16, giving options for different memory needs, firmware, and I\/O configurations. This CPU is compatible with Rockwell's Studio 5000 \/ RSLogix 5000 software environments, with a maximum supported firmware\/revision around v16 (and cannot be upgraded to newer v20+). In typical installations it acts as the central controller, executing ladder, function block, and structured text logic while coordinating communication with I\/O modules and network devices via supported interfaces such as Ethernet-based controllers and backplane connections. For reliability in applications requiring nonvolatile memory retention, many configurations use the 1756-BA1 battery module to preserve critical data between power cycles. The L55 fits standard ControlLogix racks, relying on a 1756 backplane and compatible I\/O modules to deliver scalable, modular control for manufacturing lines, packaging systems, and automated machinery that demand robust, long-term operation with a proven ecosystem.\u003c\/p\u003e\u003c\/div\u003e","brand":"Allen-Bradley","offers":[{"title":"Used Surplus - Excellent Condition","offer_id":51657301164334,"sku":null,"price":83.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0940\/0818\/1038\/files\/Ebay_website_image_650dd9d5-f964-4b0d-a489-8059c94f6857.jpg?v=1769467675","url":"https:\/\/plgautomation.com\/products\/allen-bradley-1756-l55-controllogix-controller","provider":"PLG Automation ","version":"1.0","type":"link"}