The Allen Bradley 1771-IBN is a PLC-5 series high-density DC digital input module designed for the 1771 I/O chassis platform. It is used to interface 24V DC field devices with PLC-5 controllers, converting external ON/OFF signals into internal PLC logic data.
Compared with standard 16-point input modules, the 1771-IBN provides a higher channel density (32 points), making it suitable for large-scale discrete control systems where cabinet space and I/O efficiency are critical.
Technical Specifications
| Parameter | Specification |
|---|---|
| Manufacturer | Allen Bradley (Rockwell Automation) |
| Catalog Number | 1771-IBN |
| Module Type | DC Digital Input Module |
| System Family | PLC-5 / 1771 I/O |
| Input Channels | 32 points (4 groups of 8) |
| Input Voltage Range | 10–30V DC (24V nominal) |
| Input Type | High-true DC input |
| On-State Current | ~4.7 mA @ 10V DC to ~15.6 mA @ 30V DC |
| Off-State Current | ≤ 1.7 mA @ 5V DC |
| Backplane Current Draw | ~280 mA @ 5V DC |
| Input Delay | ~6 ms (±2 ms typical) |
| Isolation | Optical isolation per group |
| Wiring Arm | 1771-WN |
| Mounting Type | 1771 chassis slot |
| Operating Temperature | 0°C to 60°C |
| Storage Temperature | -40°C to 85°C |
| Weight | ~0.40 kg |
| Dimensions (L×W×H) | 150 mm × 260 mm × 30 mm |
System Role Overview
The 1771-IBN module is responsible for reading multiple DC discrete signals simultaneously and transmitting them to the PLC-5 processor through the backplane.
Core functions include:
- High-density 32-point DC signal acquisition
- Interface for sensors and dry-contact devices
- Electrical isolation between field wiring and PLC system
- Noise filtering for industrial environments
- Efficient I/O expansion in PLC-5 racks
It is commonly used in systems requiring large numbers of sensor inputs in a compact hardware footprint.
Recommended Related Modules
| Model | Function |
|---|---|
| 1771-IAD | AC input module |
| 1771-IBD | Standard DC input module (16-point) |
| 1771-OBD | DC output module |
| 1771-OWNA | Relay output module |
| 1771-IFE | Analog input module |
| 1771-ASB | Remote I/O adapter |
Common PLC-5 System Modules
| Model | Role |
|---|---|
| 1785-L40B | PLC-5 processor |
| 1771-A4B | 16-slot I/O chassis |
| 1771-DMC | Data Highway communication module |
| 1771-SN | I/O scanner module |
| 1771-ALX | Local I/O adapter module |
