Allen-Bradley 1771-ASB/E Remote I/O Adapter Module

The Allen-Bradley 1771-ASB/E, also cataloged as the 1771-ASB Remote I/O Adapter Module, operates as a dedicated hardware component for distributed network communication management within PLC-5 platforms.

Hardware Specifications

Industrial Control & Drive Integration

The 1771-ASB/E coordinates discrete and block transfer data sequencing synchronized with the backplane bus communication velocity properties of the legacy 1771 chassis. By serving as an intermediate slave controller, the hardware executes comprehensive I/O density scaling routines across remote segments linked to higher-level Profinet / EtherNet/IP deterministic networks via network scanners. Maintaining specific firmware flash compatibility across the primary PLC-5 processor, host adapters, and the modular chassis infrastructure is necessary to verify exact input/output image mapping and prevent token-rotation transmission timeouts.

Frequently Asked Questions

Q: Does the 1771-ASB/E module support hot-swapping or card extraction while the chassis is powered?

A: No. The 1771 I/O chassis backplane design does not support Removal and Insertion Under Power (RIUP). The primary rack power supply must be completely de-energized before inserting or removing this communication adapter to prevent logic architecture damage or signal line corruption.

Q: How is the physical network speed configured on this remote adapter?

A: The communication baud rate (57.6, 115.2, or 230.4 kbaud) is configured via onboard hardware dual inline package (DIP) switch arrays located on the module housing. These switches must match the scanning master configuration to establish a synchronous data link.

Field Installation Guidelines

• Chassis Slot Insertion: Power down the 1771 assembly. Install the module into the leftmost slot (Slot 0) of the remote 1771 I/O chassis. Push the module firmly into the backplane connectors and clip the plastic chassis latches over the front edge to lock the unit.
• Network Wiring Layout: Connect the RIO twinaxial cable to the front-facing terminal connector block according to standard terminal designations (Terminal 1 to blue wire, Terminal 2 to shield drain, Terminal 3 to clear wire). Wiring inside explosive areas must conform to NEC Article 501-4(b).
• Line Termination Requirements: Install a physical termination resistor across the physical transmission lines at the final physical node of the RIO trunk link. Use a 150 Ohm or 82 Ohm resistor matched strictly to the specific baud rate and line length constraints of the implementation layout.