1771-WH (PU)

Allen Bradley Bulletin 1771 | Field Wiring Arm

Allen Bradley Bulletin 1771 | 12-Terminal Field Wiring Arm, allows module replacement without rewiring, 1771 Platform

The Allen-Bradley 1771-WH is a standard 12-terminal field wiring arm designed for the 1771 Universal I/O platform. It serves as the primary physical interface between field-side wiring and 1771 I/O modules, providing a secure and organized method for terminating sensors, switches, and actuators. It is a critical component for maintaining the "removable terminal block" functionality that is a hallmark of the PLC-5 system.

This wiring arm is engineered for use with low-to-medium density 1771 modules, such as the 1771-IA, 1771-IB, and 1771-OA. By providing a detachable termination point, the 1771-WH allows maintenance personnel to replace faulty I/O modules in seconds without the need to disconnect or re-label individual field wires. This design significantly reduces system downtime and eliminates the risk of wiring errors during module swaps.

Constructed with high-quality, impact-resistant plastic and heavy-duty screw terminals, the 1771-WH is built to withstand the rigors of industrial environments. It features a hinged design that snaps securely onto the front of the I/O module, ensuring a consistent and vibration-resistant electrical connection. The arm includes space for a custom wiring label, allowing for clear identification of signal paths for each of the 12 termination points.

The 1771-WH is rated for use across the full standard industrial temperature range (0–60°C) and is designed to handle the typical voltages associated with discrete and analog I/O control. Its robust mechanical locking mechanism ensures that the arm remains firmly seated under operational vibration. It meets UL and SA standards, providing a safe and reliable termination solution for global industrial automation installations.

Key Specifications:

  - Function: Field Wiring Arm (Removable Terminal Block)
  - Terminals: 12 Screw Terminals
  - Module Compatibility: Standard 1771 I/O (IA, IB, OA, etc.)
  - Mounting: Hinged (Front of Module)
  - Wire Size: Up to 14 AWG
  - Platform: 1771 Universal I/O (PLC-5)