Brief Product Description

Allen-Bradley 1747-ASB is a remote I/O (RIO) adapter module for Rockwell SLC 500 PLC platform. Installed in slot 0 of a 1746 remote chassis, it acts as the slave adapter on the RIO link, bridging the remote 1746 I/O modules with the local SLC scanner module. It collects input signals from remote I/O cards and transmits output commands received from the main PLC scanner over the RIO network. It supports mixed discrete and analog 1746 I/O modules, long-distance field wiring and multiple baud rate options. Equipped with three 7-segment displays for status and fault diagnosis, it offers non-volatile memory for slot configuration. Fully tested surplus and refurbished Allen-Bradley 1747-ASB modules are available for legacy SLC500 remote I/O system maintenance, adapter replacement and plant automation retrofit projects

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Core Product Functions

• Remote I/O adapter gateway for SLC 500 RIO network, connecting remote 1746 I/O racks
• Transmit output data from the main scanner to remote output modules via RIO link
• Collect input signals from remote I/O modules and send data back to the PLC scanner
• Supports mixed 1746 digital and analog I/O modules across up to 30 slots total
• Multiple selectable baud rates: 57.6K, 115.2K, 230.4K for different cable distances
• Long-distance communication up to 3040 meters at 57.6K baud for distributed field I/O
• 7-segment LED display for real-time network status, fault code and diagnostic information
• Non-volatile memory to store slot configuration, I/O mapping and node address settings
• Hold-last-state option for outputs upon RIO communication failure to improve process safety

Application Scenarios

• Legacy SLC 500 distributed remote I/O control racks with RIO network
• Large factory production lines requiring I/O placed far away from main PLC cabinet
• Water & wastewater treatment plants with widely scattered field sensors and valves
• Mining, material handling and conveyor systems with distributed I/O stations
• Petrochemical and chemical plants where field I/O must be separated from main control room
• Legacy SLC500 remote I/O adapter replacement, maintenance and plant retrofits

FAQ (Frequently Asked Questions)

• Q: Loss of remote I/O communication or fault codes showing on 7-segment display after installing 1747-ASB?
  A: Verify RIO cable continuity, check DIP switch node address and baud rate match with scanner, inspect chassis backplane contacts, check cable shielding and grounding for EMI interference.
• Q: Does Allen-Bradley 1747-ASB support hot-swap replacement?
  A: Hot swap is not supported. Back up PLC program, power down the remote chassis and perform lockout-tagout before replacement to prevent unexpected field device operation.
• Q: What module works as the paired scanner for 1747-ASB?
  A: It works with the 1747-SN scanner module installed in the local SLC main rack.
• Q: What I/O modules can the 1747-ASB control?
  A: It supports the full range of 1746 series discrete input/output and analog I/O modules.
• Q: Is Allen-Bradley 1747-ASB available for new automation projects?
  A: This legacy SLC500 remote I/O adapter module is end-of-life for new installations. Only fully tested surplus and refurbished units are supplied for existing remote I/O system maintenance and retrofits.