Overview
The Allen-Bradley 1746-IB32 is a discrete digital input module designed for the SLC 500 modular platform. This Series D device provides 32 sinking input channels at 24VDC nominal, allowing integration of sensors, switches, auxiliary contacts, and other binary or ON/OFF devices into your PLC system. The module is electrically fused per common group for protection against external wiring faults.
Key Features
- 32 sinking digital input points with 8 inputs per common group
- 24VDC nominal input voltage with wide operating range (15–30V DC @ 50°C; 15–26.4V DC @ 60°C)
- Standard 24V AC/DC LED indicators for visual status monitoring
- High-density design optimized for compact panel space
- Electrically fused protection (2.5A non-replaceable fuse per common) against external wiring damage
- Backplane current draw: 103 mA @ 5V DC
Technical Specifications
- Input Type: DC Sink (current sourced by external device)
- Nominal Input Voltage: 24VDC
- Operating Voltage Range: 15–30V DC @ 50°C (122°F) / 15–26.4V DC @ 60°C (140°F)
- Number of Input Points: 32
- Inputs per Common: 8
- Nominal Input Current: 5.1 mA @ 24V DC
- Heat Dissipation: 0.20W per point; 6.65W total
- Operating Temperature: 0 to 60°C (32 to 140°F)
- Humidity: 5 to 95% non-condensing
- Certifications: Class I, Groups A, B, C, and D, Division 2
- Weight: ~110–120 grams (0.14 kg)
- Dimensions: 4 × 13 × 15 cm
Typical Applications
The 1746-IB32 is widely used in manufacturing, process control, material handling, and general industrial automation where discrete sensor and switch signals must be monitored by the PLC:
- Manufacturing equipment control and status monitoring
- Pump and motor run-status indication
- Limit switch and proximity sensor integration
- Alarm and safety interlock inputs
- Multi-point production line signal acquisition
Compatibility & Replacements
Compatible With
- SLC 500 modular controllers (any SLC 500 processor)
- SLC 500 expansion I/O racks
- Remote I/O chassis with SLC 500 communication adapters
- Local installation in the main SLC 500 chassis
- Allen-Bradley RSLogix 500 programming software
Replaces / Drop-In Replacement For
The 1746-IB32 is a legacy discrete input module now discontinued (November 2022). It remains a drop-in replacement for earlier Series A, B, and C versions of the same part number when performing hardware swaps in existing SLC 500 systems. Verify compatibility with your system integrator before ordering to confirm fit in your control architecture.
Works With
- Allen-Bradley RSLogix 500 PLC programming
- SLC 500 discrete I/O addressing and ladder logic
- Local and Remote I/O communication networks
- 24VDC field wiring standards (IEC 61131)
