{"product_id":"allen-bradley-1771-a4b-plc-5-universal-i-o-chassis","title":"Allen-Bradley 1771-A4B PLC-5 Universal I\/O Chassis","description":"\u003cp\u003eThe \u003cstrong\u003eAllen-Bradley 1771-A4B\u003c\/strong\u003e serves as the primary \u003cstrong\u003e1771-A4B\u003c\/strong\u003e Universal Input\/Output Chassis utilized to execute physical module mounting and backplane power distribution across PLC-5 platforms.\u003c\/p\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\u003e1771-A4B\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\u003e13.36 lbs (6.06 kg)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003e16-Slot 1771 Chassis Footprint\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 \/ Capacity\u003c\/td\u003e\n\u003ctd\u003eMax 24.0 A at 5.25 VDC backplane current\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Line\u003c\/td\u003e\n\u003ctd\u003ePLC-5\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Type\u003c\/td\u003e\n\u003ctd\u003eI\/O Chassis \/ Rack\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNumber of Slots\u003c\/td\u003e\n\u003ctd\u003e16 Slots\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRated Voltage\u003c\/td\u003e\n\u003ctd\u003e5.25 VDC (Backplane)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMounting Style\u003c\/td\u003e\n\u003ctd\u003ePanel Mount \/ 19-inch Rack Mount\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003ch3\u003eDeterministic Backplane \u0026amp; Power Scaling\u003c\/h3\u003e\n\u003cp\u003eThe hardware structure ensures backplane bus communication velocity and signal integrity across all 16 slot positions. Designed to handle backplane bus current loads up to 24 A at 5.25 VDC, the chassis provides low-impedance power routing and physical card guidance for a full array of I\/O, processor, and communication modules. The mechanical alignment slots enforce rigid connector mating, eliminating transmission attenuation and preserving backplane bus scanning speed across high-density I\/O configurations.\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003eQ: What is the maximum backplane current rating for the 1771-A4B chassis?\u003c\/p\u003e\n\u003cp\u003eA: The chassis backplane bus is rated to deliver up to 24 A at 5.25 VDC. Total combined current draw of all installed processor, adapter, and I\/O modules must not exceed this limit.\u003c\/p\u003e\n\u003cp\u003eQ: Can any module be placed in Slot 0 of the 1771-A4B?\u003c\/p\u003e\n\u003cp\u003eA: No. Slot 0 (the leftmost slot) is reserved specifically for local PLC-5 processors, Remote I\/O adapters (such as the 1771-ASB), or ControlNet interface modules that drive the backplane bus.\u003c\/p\u003e\n\u003ch3\u003eField Installation Guidelines\u003c\/h3\u003e\n\u003col\u003e\n\u003cli\u003eMount the chassis securely to a grounded panel or enclosure backplate using standard mounting hardware to prevent mechanical vibration and stress on card connections.\u003c\/li\u003e\n\u003cli\u003eConnect a heavy-gauge copper bonding jumper (minimum 10 AWG) from the dedicated enclosure ground lug directly to the central chassis grounding terminal.\u003c\/li\u003e\n\u003cli\u003eEnsure adequate clearance (minimum 2 inches \/ 50.8 mm) around the top, bottom, and sides of the rack to maintain proper thermal heat dissipation profile.\u003c\/li\u003e\n\u003cli\u003eVerify power supply voltage outputs (5.25 VDC nominal) before connecting external power supplies to the backplane wiring arm or power connectors.\u003c\/li\u003e\n\u003cli\u003eFully seat all 1771 I\/O cards into their respective slot guide rails and engage top\/bottom latching arms before applying system power.\u003c\/li\u003e\n\u003c\/ol\u003e","brand":"Allen-Bradley","offers":[{"title":"Default Title","offer_id":48784589881534,"sku":"1771-A4B","price":99.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0725\/1145\/5422\/files\/1771-A4B_6b61324c-603e-44cb-9248-fb0010896b0a.png?v=1787650384","url":"https:\/\/www.autooiltech.com\/products\/allen-bradley-1771-a4b-plc-5-universal-i-o-chassis","provider":"AutoOilTech Limited","version":"1.0","type":"link"}