Allen-Bradley 1771-A3B/B 12-Slot I/O Chassis – PLC-5 Programmable Controller Series
Imagine a critical production line suddenly halting because the I/O chassis holding your PLC-5 modules fails — no signal routing, no process control, no output. Conveyor belts stop, robotic arms freeze, and every second of downtime translates directly into lost revenue and missed delivery commitments. The Allen-Bradley 1771-A3B/B 12-Slot I/O Chassis is the structural backbone that prevents exactly this scenario, providing a robust, electrically sound housing for up to 12 I/O modules in demanding industrial environments.
Within the Allen-Bradley 1771 family — the cornerstone of Rockwell Automation’s legacy PLC-5 platform — the 1771-A3B/B occupies the mid-to-large capacity tier, offering 12 module slots that balance system density with installation flexibility. Deployed across tens of thousands of facilities worldwide in automotive, oil & gas, food & beverage, and heavy manufacturing, this chassis remains one of the most widely specified I/O racks in legacy PLC-5 installations globally.
Technical Specifications
- Part Number: 1771-A3B/B
- Brand: Allen-Bradley (Rockwell Automation)
- Series: 1771 PLC-5 I/O Chassis
- Number of Slots: 12
- Chassis Type: Single-slot addressing compatible
- Backplane: 1771 parallel I/O backplane
- Compatible Processors: PLC-5 family processors (1785 series)
- Power Supply Compatibility: 1771-P series power supplies
- Weight: Approx. 8.2 kg
- Mounting: Panel or rack mount
- Condition Available: Refurbished / Used / New Old Stock
Key Features & Benefits
- 12 Full-Width Module Slots — Accommodates a wide range of 1771 I/O modules including digital, analog, and specialty modules without compromise.
- Robust Backplane Architecture — The 1771 parallel backplane ensures reliable, high-speed communication between the processor and all installed I/O modules.
- Proven Industrial Durability — Engineered for continuous operation in harsh environments including high vibration, temperature extremes, and electrically noisy plant floors.
- Drop-in Replacement Compatibility — Direct replacement for existing 1771-A3B/B installations with no rewiring or software changes required.
- Scalable System Design — Supports multi-chassis configurations via 1771-SN Remote I/O Scanner for distributed control architectures.
- Long Service Life — Designed for 24/7 industrial duty cycles, making it ideal for facilities that cannot afford unplanned downtime.
Industry & Equipment Applications
- Automotive Manufacturing: Body welding lines, paint shop conveyors, assembly transfer systems
- Oil & Gas: Pipeline monitoring stations, compressor control panels, wellhead automation
- Food & Beverage: Bottling lines, pasteurization control, packaging machinery
- Pulp & Paper: Winder control systems, digester automation, conveyor management
- Water & Wastewater: Pump station control, SCADA-integrated treatment plant automation
- Heavy Manufacturing: Steel mill rolling lines, press control, material handling systems
System Integration & Compatible Parts
The 1771-A3B/B chassis is designed to integrate seamlessly within the Allen-Bradley PLC-5 ecosystem. Compatible and commonly paired components include:
- Processors: 1785-L20B, 1785-L40B, 1785-L60B, 1785-L80B (PLC-5 family)
- Power Supplies: 1771-P4S, 1771-P6S, 1771-P7
- I/O Modules: 1771-IAD, 1771-OAD, 1771-IFE, 1771-OFE (digital & analog)
- Remote I/O Scanner: 1771-SN for multi-rack distributed systems
- Adapter Modules: 1771-ASB Remote I/O Adapter
- Programming Software: RSLogix 5 (Rockwell Automation)
Our Quality Assurance Process
At Konmask.com, every Allen-Bradley 1771-A3B/B unit undergoes a rigorous multi-stage inspection before shipment:
- ✅ Visual Inspection: Chassis frame, backplane connectors, and slot guides checked for physical damage or corrosion
- ✅ Backplane Continuity Test: All backplane signal and power rails verified for electrical integrity
- ✅ Slot Alignment Check: Module guide rails inspected to ensure smooth, secure module insertion
- ✅ Functional Verification: Where applicable, units are powered and tested with compatible modules
- ✅ Secure Packaging: Anti-static packaging with foam cushioning for safe international shipping
How to Order
- Submit your inquiry via the Contact / Request a Quote form on this page
- Include your required quantity, delivery timeline, and destination country
- Our technical team will respond within 24 business hours with availability, lead time, and pricing
- Upon confirmation, we issue a proforma invoice and arrange secure international shipping
📧 Email: support@konmask.com | 📞 Phone/WhatsApp: +0086 19859288691
Why Choose Konmask.com?
- 🌐 Global B2B Supplier — Serving industrial buyers across 50+ countries with reliable sourcing of legacy and current-generation automation components
- 🔍 Specialist Expertise — Deep technical knowledge of Allen-Bradley, Siemens, Mitsubishi, Omron, and other leading PLC/DCS platforms
- 📦 Fast Fulfillment — In-stock items typically ship within 3–5 business days; expedited options available
- 🛡️ Quality Guaranteed — All units inspected and tested; warranty provided on refurbished stock
- 💬 Dedicated Support — Pre-sales technical consultation and post-sales support from our engineering team
Frequently Asked Questions
Q: Is the 1771-A3B/B compatible with all PLC-5 processors?
A: Yes, the 1771-A3B/B chassis is compatible with the full range of Allen-Bradley PLC-5 processors in the 1785 series, including L20B, L40B, L60B, and L80B variants, when used with the appropriate power supply.
Q: Can I mix digital and analog I/O modules in the same chassis?
A: Yes. The 1771-A3B/B supports any combination of 1771-series I/O modules across its 12 slots, including digital input/output, analog, and specialty communication modules.
Q: What is the difference between 1771-A3B and 1771-A3B/B?
A: The “/B” suffix denotes a hardware revision (Series B) of the original 1771-A3B chassis. The Series B revision incorporates minor manufacturing improvements but maintains full backward compatibility with all 1771 I/O modules and PLC-5 processors.
Q: Do you provide a warranty on refurbished units?
A: Yes. Refurbished 1771-A3B/B units sold through Konmask.com include a limited warranty. Please contact us for specific warranty terms applicable to your order.
Q: Can this chassis be used in a remote I/O configuration?
A: Yes. When equipped with a 1771-ASB Remote I/O Adapter module, the 1771-A3B/B can function as a remote I/O rack connected to a PLC-5 processor via the 1771-SN Remote I/O Scanner.
Q: What is the minimum order quantity?
A: We supply single units as well as bulk quantities. There is no minimum order requirement. Contact us with your specific needs.
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Original Source: https://Konmask.com
Contact: support@konmask.com | +0086 19859288691
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