Overview
The Allen-Bradley 1771-OG is a discrete TTL output module designed for legacy PLC-5 systems. This module controls eight TTL outputs and interfaces directly with TTL-compatible devices. The 1771-OG version features a 1ms output filter, enabling precise timing control in industrial automation and process control applications. This module is essential for systems requiring direct TTL-level output switching without additional signal conditioning.
Key Features
- Eight TTL outputs per module
- 1ms output filter for signal conditioning
- TTL voltage ranges: 0–0.5V DC (low), 2.7–5.25V DC (high)
- Sourcing current 1mA; sinking current 20mA
- Configurable positive/negative logic via DIP switches
- Nine red LED indicators on front panel; eight LEDs indicate output status
Technical Specifications
- Power requirement: 168mA @ 5V DC (backplane)
- Output voltage range: 2.0–5.25V DC (ON); -0.2–0.8V DC (OFF)
- Maximum output current source: 1mA; sink: 20mA
- Output signal delay: <1ms
- Power dissipation: 2.2W (max), 0.8W (min)
- Operating temperature: 0–60°C (32–140°F); humidity 5–95% non-condensing
- Storage temperature: -40–85°C (-40–185°F)
Typical Applications
- PLC-5 systems requiring TTL output control
- Legacy industrial automation and process control
- Equipment interfaces with TTL input requirements
- Real-time discrete output switching with minimal latency
Compatibility & Replacements
Compatible With
- Allen-Bradley Universal I/O Chassis: 1771-A1B, 1771-A2B, 1771-A3B, 1771-A4B
- PLC-5 processor-based systems
- 1771 series I/O backplane
Replaces / Drop-In Replacement For
The Allen-Bradley 1771-OG is the 8-point predecessor to the 1771-OGD (16-point). It is not directly interchangeable with the 1771-OGD due to different output counts and keying requirements. Verify compatibility with your system integrator before ordering.
Works With
- Allen-Bradley PLC-5 programming software
- Ladder logic editors and RSLogix 5
- TTL input devices meeting voltage specification (-0.2V to +0.8V low, 2.0V to 5.25V high)
- 1771-WC field wiring arm (included or sold separately)
