{"product_id":"allen-bradley-1771-a4b-module-rack","title":"Allen-Bradley 1771-A4B Module Rack","description":"\u003cdiv\u003e\u003cp\u003eAllen-Bradley 1771-A4B Module Rack is a 16-slot I\/O chassis designed for 1771-series modules used in PLC-5 and SLC 500 control systems. The A4B designation identifies a 16-slot backplane that supports up to sixteen modules in a single chassis, integrating with the 1771 backplane and providing the electrical interconnections that let I\/O modules communicate with the controller. This module rack serves as the physical backbone for modular I\/O in legacy automation installations, enabling centralized mounting of digital and analog I\/O modules in a compact enclosure. It is listed in product catalogs and literature as the 1771-A4B I\/O chassis and is described as a 16-slot rack suitable for use with 1771-series components, making it a common choice for expanding PLC-5\/SLC 500 I\/O capacity. Typical applications include machine control, process automation, and general factory automation where modular I\/O expansion is needed in a single chassis. The 16-slot format supports scalable I\/O configurations in one enclosure, contributing to organized panel layouts and straightforward wiring in industrial environments.\u003c\/p\u003e\u003c\/div\u003e","brand":"Allen-Bradley","offers":[{"title":"Used Surplus - Excellent Condition","offer_id":46244003512554,"sku":null,"price":97.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0716\/8039\/3450\/files\/GTG-STOCK-079.png?v=1788727429","url":"https:\/\/gtghardware.com\/products\/allen-bradley-1771-a4b-module-rack","provider":"GTG Hardware","version":"1.0","type":"link"}