1747-SN/B Allen-Bradley RIO Scanner Module | SLC 500 DH+

When Remote Chassis Data Stalls: The 1747-SN/B Solution

A production line expands, and the SLC 500 processor must reach I/O racks 3000 meters away. Without a dedicated scanner, the processor cannot poll remote chassis or exchange block data. The Allen-Bradley 1747-SN/B solves this exact problem. As a Remote I/O (RIO) scanner and DH+ network interface module, it lets an SLC processor communicate with remotely located 1746 I/O chassis and other RIO-compatible devices. The /B suffix denotes Series B firmware.

1747-SN/B Key Features and Verified Specifications

• Function: Remote I/O scanner plus Data Highway Plus interface.
• RIO baud rates: 57.6, 115.2, or 230.4 Kbps.
• Logical racks: Up to 4 racks (32 in/32 out words) discrete.
• Block transfer: Up to 64 words on Series B.
• Max RIO distance: 3048 m.
• DH+ addressing: Node address set via DIP switch.
• Backplane draw: 600 mA at 5V DC; 90 mA at 24V DC.
• Operating temperature: 0 to 60 C.
• Mounting: Single SLC 500 chassis slot.

The 3048 m RIO distance is the standout parameter. It allows remote chassis placement far from the main control cabinet, reducing field wiring runs. Every value above traces to the official Rockwell per-model product page.

Integrating the 1747-SN/B into SLC 500 Systems

The module occupies one slot in a 1746 chassis. Slot 0 stays reserved for the processor or a 1747-ASB adapter. The 1746 backplane supplies 5.1V DC at 10A and 24V DC at 2.88A to all modules. Field-side load power requires an external supply. Because the 1747-SN/B is not hot-swappable, do not install, remove, or wire it with power applied. For DH+ networks, set the node address with the DIP switch before commissioning. Integration Note: wiring into DH+ may require an external gateway or connection module; confirm cables and gateways with the supplier.

Reliability and Maintenance for the 1747-SN/B

Inspect the module and terminal blocks periodically. Verify backplane seating and DIP switch settings after any panel work. Keep ambient temperature within 0 to 60 C and humidity within 5-95% RH non-condensing. Since the unit is discontinued (2024-03-31), spare-part planning matters. The engineering replacement is the 5069-AENTR. Contact AutoDCSTech with your exact requirements for precise matching.