Overview
The Allen-Bradley 1771-WHF is a fused field wiring swing arm designed for integration with Allen-Bradley PLC-5 processor systems. This modular wiring component provides safe, isolated power distribution to 1771 I/O modules in rack-based automation systems. The swing arm design allows technicians to remove or service modules without disconnecting field wiring, reducing downtime in production environments.
Key Features
- Fused protection: 3-amp maximum fuse current rating with built-in fuse holder
- Swing arm pivot design: Allows full module removal while maintaining field wiring connections
- 21-terminal configuration: Supports multiple I/O module connections and power distribution
- Conformal coating: Protects against moisture and contamination in harsh industrial environments
- Field-wirable terminals: Accepts standard crimp and screw-down wire connections
- Distributed I/O support: Works with PLC-5 networks for modular automation architectures
Technical Specifications
- Fuse Rating: 3 Amps maximum
- Terminal Count: 21 terminals
- Wiring Points: 16-point field-wirable configuration
- Coating: Conformal coating for environmental protection
- Dimensions: 4.5 inches (W) × 12.4 inches (H) × 6.3 inches (D)
- Weight: 0.3 pounds (0.1 kg)
- Revision: Rev F01
- Catalog Number: 1771-WHF
- System Compatibility: Allen-Bradley PLC-5 processor family
- Terminal Type: Screw-down and crimp compatible
Typical Applications
- PLC-5 distributed I/O rack assemblies in manufacturing plants
- Power distribution to remote I/O modules in production machinery
- Process control systems requiring modular, safe power distribution
- Industrial automation environments where module serviceability is critical
- Packaging, automotive, food processing, and semiconductor applications
Compatibility & Replacements
The 1771-WHF is a standard fused wiring arm for Allen-Bradley PLC-5 systems. This part integrates with the complete 1771 I/O family, including discrete input, discrete output, analog input, and analog output modules. The swing arm design is compatible with all 1771-series modules in single-slot or multi-slot configurations. For applications requiring unfused wiring distribution, Allen-Bradley offers the 1771-WH as an alternative. Always verify module slot compatibility and power budget requirements before installation. This discontinued but widely supported legacy component remains available through industrial surplus distributors and authorized resellers.












