Overview
The Allen-Bradley 1771-OD16 /B is a 16-point isolated AC output module designed for use in PLC-5 systems within the 1771 I/O chassis family. This Series B module provides solid-state switching of AC loads and is optimized for controlling devices such as motor starters, pilot lights, and solenoids in industrial automation applications. The module features electrical-optical isolation and filter circuits for system protection and reliable troubleshooting.
Key Features
- 16 isolated outputs — each capable of 2A pilot duty switching
- 120V AC operating range — 74–138V AC nominal supply
- Electrical-optical isolation — protects PLC logic from field transients
- Long operational life — 20–100 million operations per output
- Built-in status indicators — red LED indicators show output state and blown-fuse conditions
- Series B I/O chassis compatible — plug-and-play installation with standard keying
Technical Specifications
- Part Number: 1771-OD16 /B
- Module Type: Isolated AC Output (120V)
- Output Channels: 16 points, individually isolated
- Output Voltage Rating: 120V AC, 74–138V AC operating range
- Output Current: 2A per point (pilot duty)
- Max Leakage (Off-State): 5 mA at 138V AC
- On-State Voltage Drop: ≤2.0V AC at 100 mA
- Chassis Compatibility: 1771 Series B I/O chassis
- Module Position: Any slot except leftmost (reserved for processor/adapter)
- Operating Life: 20–100 million operations
- Status Indicators: 16 red LEDs (output state + blown-fuse indication)
- Electrical Safety: CSA C22.2 No. 142
Typical Applications
- Motor starter control in manufacturing and process control systems
- Solenoid valve actuation for fluid and pneumatic control
- Pilot light and indicator lamp switching
- General-purpose load switching in industrial automation (up to 2A per point)
- Legacy PLC-5 system maintenance and expansion
Compatibility & Replacements
The 1771-OD16 /B is designed for direct installation in Series B 1771 I/O chassis. Common paired input modules include the 1771-ID16 (AC/DC isolated input module). Related output modules in the 1771 family include the 1771-OM, 1771-OMD, and 1771-OR, though the 1771-OD16 /B is the standard choice for isolated 120V AC switching. Note that module placement may require adjacent even/odd slot pairing depending on system configuration. Always consult your I/O chassis documentation and cross-reference module keying bands before installation.
