1771-ASB Ser B (PU)

Allen Bradley Bulletin 1771 | Remote I/O Adapter

Allen Bradley Bulletin 1771 | Remote I/O Adapter Module, Series B, connects 1771 chassis to RIO Link (Blue Hose) PLC-2,-3,-5, Series B

The Allen-Bradley 1771-ASB is a high-performance Remote I/O (RIO) adapter module designed for the 1771 Universal I/O platform. It serves as the critical communication link between a host controller—such as a PLC-5 scanner or a ControlLogix RIO scanner—and the I/O modules residing in a remote 1771 chassis. This allows for distributed control systems where I/O can be placed close to the field devices, significantly reducing long-distance wiring costs.

This Series B module interfaces with the host via the standard "Blue Hose" (Twinax) Remote I/O network. It supports reliable communication across varying distances with selectable baud rates of 57.6 kbps, 115.2 kbps, and 230.4 kbps. The adapter manages all data exchange between the host and the local 1771 backplane, ensuring that input and output data is refreshed accurately and deterministically within the control cycle.

The 1771-ASB features a set of front-panel status LEDs (Active, Adapter Fault, and I/O Rack Fault) that provide immediate diagnostic feedback for troubleshooting network or hardware issues. Configuration is handled through internal DIP switches, allowing users to set the starting rack address and baud rate without the need for specialized software. It is highly versatile, supporting 1/2-slot, 1-slot, and 2-slot addressing modes to accommodate various I/O densities.

Built for heavy industrial use, the module operates within a temperature range of 0–60°C (32–140°F) and 5–95% non-condensing humidity. It draws 1.0A of current at 5VDC directly from the chassis backplane. The 1771-ASB is designed to withstand the electrical noise and vibration common in factory environments and is UL listed, CSA certified, and CE compliant for global industrial deployment.

Key Specifications:

- Function: Remote I/O Adapter
- Network: Allen-Bradley Remote I/O (RIO) "Blue Hose"
- Baud Rates: 57.6k, 115.2k, 230.4k bps
- Addressing Support: 1/2, 1, and 2-Slot
- Backplane Current: 1.0A @ 5VDC
- Platform: 1771 Universal I/O (PLC-5)
- Series: B