Overview
The Allen-Bradley 1747-ASB is a universal remote I/O adapter module designed for SLC 500 automation systems. The module functions as a slave on the RIO link and master of the remote chassis and expansion chassis it is installed in, acting as a gateway between the scanner and I/O modules residing in the remote and expansion chassis. The adapter is capable of controlling 30 slots, and when expansion chassis are used, it treats all I/O modules as if installed in a single chassis, with slots numbered from 0 to 30.
Key Features
- Compatible with all Allen-Bradley scanners, supporting both discrete and block transfer operations
- Supports all SLC 5/01 compatible I/O modules (class 0 and 1), including all discrete and analog I/O modules
- Flexible communication rates supporting 57.6 kbps, 115.2 kbps, and 230.4 kbps
- LED diagnostic indicators provide clear module and communication status for quick troubleshooting
- Supports distances up to 10,000 feet at 57.6 KBaud, 5,000 feet at 115.2 KBaud, and 2,500 feet at 230.4 KBaud
- DIP switch configuration for addressing mode, specialty I/O mode, and module keying
Technical Specifications
- Backplane Current Consumption: 375 mA at 5V DC
- Operating Temperature: 32°F to 140°F (0°C to 60°C)
- Storage Temperature: -40°F to +185°F (-40°C to +85°C)
- Humidity: 5% to 95% non-condensing
- Certifications: Class I, Groups A, B, C, D, Division 2
- Communication Rates: 57.6 kbps, 115.2 kbps, 230.4 kbps (selectable via DIP switch)
- Slot Capacity: 30 slots total across remote and expansion chassis
- Module Image Size: 2 to 32 logical groups (4 logical racks maximum)
Typical Applications
The module implements distributed I/O applications over a Remote I/O network, overcoming the limitations of SLC expansion buses which have limited cable length and chassis expansion capability. Common uses include:
- Distributed control systems requiring remote I/O racks across manufacturing facilities
- Machine integration with multiple remote sensor and actuator cabinets
- SCADA-based systems with remote data acquisition and supervisory control
- Multi-location production lines coordinated from a central SLC processor
Compatibility & Replacements
The 1747-ASB module is compatible with all Allen-Bradley scanners, though scanners that do not support RIO block transfers do not work with all I/O modules supported by the 1747-ASB, such as the 1747-SN Series A which does not support block transfer with the 1746-BAS BASIC module. This Series A version is a direct replacement for legacy installations and integrates with RSLogix 500 and Studio 5000 programming environments. Verify scanner capabilities for full I/O module compatibility before installation.
