Allen‑Bradley 1771‑IBDB Digital Input Module

The Allen‑Bradley 1771‑IBDB is a digital input module developed for Rockwell PLC‑5 programmable controller systems. It collects 24V DC discrete switch signals from field sensors, limit switches and relay contacts, converting on‑off status into digital data transmitted to the PLC‑5 controller for logic judgment and interlock control.

This plug‑in chassis module is compatible with the 1771 I/O rack backplane. It provides channel status indication and built‑in surge suppression, widely stocked as spare parts for maintenance and upgrade of legacy PLC‑5 automation systems in traditional manufacturing and water treatment plants.

Main Specifications

• Brand: Allen‑Bradley (Rockwell Automation); Model: 1771‑IBDB; Type: DC Digital Input Module
• Applicable System: PLC‑5 programmable controller, 1771 series I/O rack system
• Core Tasks: 24VDC discrete signal acquisition, signal conditioning, digital data upload, channel status indication
• Signal Interface: Field wiring terminal assembly, 1771 backplane connector
• Installation: Plug‑in slot‑mount on standard 1771 I/O chassis rack
• Signal Type: 24V DC sink/source discrete input for field switches and sensors
• Operating Environment: 0℃ ~ +60℃, 5%‑95% RH non‑condensing, industrial anti‑vibration grade
• Mechanical: Standard 1771 series module form‑factor, IP20 cabinet‑mount installation
• Certifications: CE, meets Rockwell legacy automation EMC requirements

Core Functions

• Capture 24VDC switch state signals from field limit switches, proximity sensors and relay auxiliary contacts for PLC‑5 control logic processing.
• Complete signal filtering and surge suppression to avoid false triggering caused by transient voltage interference in industrial field circuits.
• Front‑panel LED indicators display real‑time on/off status of each channel for convenient on‑site wiring verification and fault troubleshooting.
• Transmit collected discrete data to PLC‑5 controller through 1771 rack backplane bus to realize equipment interlock and sequence control.
• Adopt chassis plug‑in structure for quick assembly and disassembly inside the 1771 I/O cabinet during maintenance work.
• Industrial‑grade circuit design supports long‑term continuous operation for retrofitting projects of legacy PLC‑5 automation equipment.

Application Scenarios

• Spare‑part replacement for legacy PLC‑5 automation cabinets in manufacturing, water treatment and old petrochemical industrial sites.
• Discrete input hardware for collecting field switch and sensor signals of 1771 I/O rack control systems.
• Maintenance backup inventory for renovation and after‑sales maintenance projects of end‑of‑life Rockwell PLC‑5 automation equipment.
• Matching digital input module cooperating with PLC‑5 CPU, 1771 chassis, terminal arms and output modules.
• Retrofit replacement for aged input modules with channel loss, signal misjudgment and indicator failure faults.

• Global aftermarket spare supply for automation maintenance teams maintaining Rockwell legacy industrial‑control equipment worldwide.