Overview
The Allen-Bradley 1771-RTP4 is a remote termination panel (RTP) designed for use with 1771-N series high-resolution isolated analog I/O modules in PLC-5 automation systems. This general-use termination block provides a simplified wiring interface between field devices and distributed I/O racks, eliminating the need for complex terminal strips and wiring arms while maintaining system integrity during hot swaps.
Key Features
- Supports up to 8 I/O modules simultaneously
- Straight-through wiring for straightforward field connections
- Compatible with current and voltage input devices
- DIN rail mountable (1 or 3-rail compatible)
- Two 25-pin D-Sub female connectors for 1771-NC6 cables
- Allows I/O module removal without disrupting active current loops
Technical Specifications
Physical:
- Dimensions: 75 mm × 138 mm × 58 mm (3.0 in × 5.3 in × 3.0 in)
- Weight: 0.2 kg (0.44 lbs)
- Screw Terminals: 38
- Connectors: 2 × 25-pin female D-Sub
Environmental:
- Operating Temperature: 0–60°C (32–140°F)
- Relative Humidity: 0–95% (non-condensing)
- Mounting: DIN rail (standard 1 or 3-rail)
Functional:
- I/O Channels: 8
- Wiring Type: Straight-through
- Cable Length: Two 1.8 m (6 ft) 1771-NC6 pre-fabricated cables
- Series: PLC-5 1771-N High-Resolution Isolated Analog
Typical Applications
The 1771-RTP4 is widely used in:
- Distributed analog signal termination in process control systems
- Remote sensor and transducer interface in industrial plants
- Temperature and pressure monitoring (RTD and voltage input)
- Multi-module I/O expansion without field rewiring
- Legacy PLC-5 retrofit and modernization projects
Note: Not suitable for thermocouple applications unless junction compensation is provided.
Compatibility & Replacements
The 1771-RTP4 is a PLC-5 era component and has been discontinued by the manufacturer. It is designed exclusively for use with 1771-N series high-resolution analog input/output modules and connects via two pre-fabricated 1771-NC6 cables. Modern equivalents in current-generation Rockwell Automation systems include CompactLogix and ControlLogix with integrated analog I/O or remote adapter modules, but direct pin-for-pin replacement is not possible due to platform differences. For legacy system support, the 1771-RTP4 remains the standard interface panel. Refurbished and surplus units are widely available through industrial automation distributors.
