{"product_id":"1771-a1b-allen-bradley-plc-expansion-chassis-4-slots","title":"1771-A1B Allen-Bradley PLC Expansion Chassis 4 Slots","description":"\u003ch3\u003eProduct Overview\u003c\/h3\u003e\n\u003cp\u003eThe\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eAllen Bradley 1771-A1B\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eserves as the structural and electrical foundation for modular PLC-5 systems. This 4-slot universal I\/O chassis houses and interconnects various 1771-series digital, analog, and specialty modules. It facilitates high-speed data communication across the backplane, ensuring seamless integration between the processor and field devices. Designed for compact footprints, it provides a rugged environment for critical automation control in demanding industrial settings.\u003c\/p\u003e\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cp\u003eWe provide only\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003e100% Brand New and Original\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eunits to ensure maximum uptime for your control architecture.\u003c\/p\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr class=\"firstRow\"\u003e\n\u003ctd\u003e\u003cstrong\u003eSpecification\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003eDetails\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003e\u003cstrong\u003eNumber of Slots\u003c\/strong\u003e\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003e4 Module Slots\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003e\u003cstrong\u003eBackplane Current\u003c\/strong\u003e\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003e8 Amps at 5V DC\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003e\u003cstrong\u003eChassis Type\u003c\/strong\u003e\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003eUniversal I\/O Rack\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003e\u003cstrong\u003eMounting Options\u003c\/strong\u003e\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003ePanel or 19-inch Rack Mount\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003e\u003cstrong\u003eOperating Temp\u003c\/strong\u003e\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003e0 to 60 degrees C (32 to 140 degrees F)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003e\u003cstrong\u003eStorage Temp\u003c\/strong\u003e\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003e-40 to 85 degrees C (-40 to 185 degrees F)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003e\u003cstrong\u003eCompatible Power Supplies\u003c\/strong\u003e\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003e1771-P4, 1771-P7, 1771-PS7\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003e\u003cstrong\u003eRelative Humidity\u003c\/strong\u003e\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003e5 to 95 percent (non-condensing)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan\u003e\u003cstrong\u003eWeight\u003c\/strong\u003e\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan\u003e7.69 lbs (3.5 kg)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eEngineering Advantages\u003c\/h3\u003e\n\u003cp\u003eThe 1771-A1B offers specific mechanical and electrical benefits that resolve common installation pain points:\u003c\/p\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eSpace Optimization:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eThe 4-slot form factor solves space constraints in small control cabinets or remote junction boxes where a full-sized 16-slot rack proves impractical.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eRobust Signal Integrity:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eThe gold-plated backplane connectors resist oxidation and maintain high-conductivity paths even in high-vibration environments.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eThermal Management:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eThe chassis design incorporates specific airflow channels. When users maintain the required 102 mm horizontal and 153 mm vertical clearance, the unit dissipates heat efficiently, preventing module derating.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eSimplified Troubleshooting:\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eThe chassis includes an integrated ground bus. This simplifies wiring and reduces electromagnetic interference (EMI), which often causes intermittent signal drops in analog modules.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eFAQs\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eCan I use 1\/2 slot, 1-slot, or 2-slot addressing with this chassis?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eYes. The 1771-A1B supports all standard PLC-5 addressing modes. You configure the addressing via the DIP switches located on the backplane to match your software's I\/O configuration.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the difference between the 1771-A1B and the 1771-A1B\/B?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe \"\/B\" designation refers to Series B. Series B units often include minor mechanical refinements or updated backplane components for better noise immunity compared to the original Series A, though they remain functionally interchangeable.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes this chassis require a separate power supply?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eYes. The chassis does not generate its own power. You must install a compatible 1771 power supply module (like the 1771-P4) or use a standalone power supply wired to the backplane terminals.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I mix different types of modules in these 4 slots?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eAbsolutely. You can mix digital, analog, and intelligent modules (such as counters or flow meters) within the same chassis, provided the total current draw does not exceed the 8A backplane limit.\u003c\/p\u003e","brand":"Allen Bradley","offers":[{"title":"Default Title","offer_id":43377637851226,"sku":"1771-A1B","price":99.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0710\/5957\/0778\/files\/19._671bf688-f726-43c2-a0f6-f1517dcc1ad6.jpg?v=1778811445","url":"https:\/\/www.spareoil.com\/products\/1771-a1b-allen-bradley-plc-expansion-chassis-4-slots","provider":"SpareOil Automation","version":"1.0","type":"link"}