Overview
The Allen-Bradley 1746-IA8 is an 8-point AC input module from the SLC 500 discrete I/O family. It provides 8 grouped AC digital input channels within an operating range of 85–132V AC at 47–63 Hz, with nominal operation at 100–120V AC. This 8-channel digital AC input module is designed for general-purpose input applications in legacy and maintenance environments where SLC 500 platforms remain critical infrastructure.
Key Features
- 8 grouped AC digital input channels within an operating range of 85–132V AC at 47–63 Hz
- Nominal input current of 12 mA at 120V AC with response times of up to 35 ms ON and 45 ms OFF
- Isolation voltage of 500V DC at the communication circuit and 1500V AC at the back-plane
- Chassis-style mounting with 8 channels in a single slot
- North American Hazardous Location Approval rating for safe operation in certain types of hazardous environments
- Status display and open-style enclosure for easy diagnostics
Technical Specifications
- Input Voltage: 85–132V AC, 47–63 Hz
- Input Current: 12 mA nominal at 120V AC
- Response Time: Up to 35 ms ON, 45 ms OFF
- Heat Dissipation: 0.27 W per input point, 2.4 W maximum total
- Dimensions: 5″ × 2″ × 6″ (13 cm × 5 cm × 15 cm)
- Weight: 0.23 kg
- Operating Temperature: 32–140°F (0–60°C)
- Vibration Rating: 1G at 10–2000 Hz; Shock: 50G non-operating, 30G operating
- Backplane Current: 50 mA at 5V DC; 0 mA at 24V DC
Typical Applications
This module is suitable for general-purpose automation tasks, providing dependable signal acquisition from AC sources. Common applications include:
- Digital AC signal monitoring in legacy SLC 500 control systems
- Machine control and interlocking circuits
- Sensor and limit switch acquisition in manufacturing environments
- General-purpose industrial process monitoring
- Maintenance and upgrade of existing SLC 500 installations
Compatibility & Replacements
Compatible With
- SLC 500 processors via the 1746 I/O platform
- 1746-HT and 1746-HCA terminator connections
- SLC 500 discrete I/O chassis with 1746 backplane
- Allen-Bradley programming software (RSLogix 500)
Replaces / Drop-In Replacement For
The 1746-IA8 is the original equipment module for SLC 500 systems. The 1746-IA8 was officially discontinued by Allen-Bradley on August 19, 2018, but remains widely available through secondary market channels for maintenance and legacy system support. For legacy system maintenance, verify compatibility with your existing SLC 500 configuration before ordering.
Works With
- RSLogix 500 programming software
- Allen-Bradley SLC 500 architecture
- Standard 24V DC and 5V DC backplane supplies
- 1746 series I/O terminators and connectors
