Allen-Bradley 1771-OGD Series B TTL Output Module 16-PT

Allen-Bradley 1771-OGD Series B PLC-5 Digital DC TTL 16-Point Output Module

Product Description

The Allen-Bradley 1771-OGD (Part Number: 1771-OGD/B) is a 16-point Transistor-Transistor Logic (TTL) digital output module engineered for the legacy PLC-5 / 1771 I/O platform. This module is specifically designed for high-speed, low-voltage applications where interfacing with logic-level electronics is required. It provides precise digital signaling to drive TTL-compatible devices such as solid-state relays, integrated circuit logic gates, and LED indicators.

Utilizing an open-collector transistor design with internal 1 kΩ pull-up resistors, the 1771-OGD ensures reliable switching performance and noise immunity through optical isolation between the field-side circuits and the controller backplane. As a mature product within the Rockwell Automation lifecycle, the 1771-OGD/B remains a critical component for maintaining and expanding existing PLC-5 systems, offering a ruggedized solution for high-speed digital control without the need for interposing relays in low-power logic environments.

Technical Specifications

The following technical parameters define the operational limits of the 1771-OGD module:

Key Features

• TTL Compatibility: Designed to interface directly with 5V logic circuits without additional signal conditioning.

• High-Speed Switching: Optimized for rapid digital signaling in precise timing applications.

• Optical Isolation: Protects the PLC-5 processor and backplane from field-side electrical noise or transients.

• Open-Collector Design: Provides flexible integration with various pull-up configurations for diverse logic-level requirements.

• Diagnostic LEDs: Immediate visual verification of output state for simplified troubleshooting.

Industrial Application Scenarios

• Logic Interfacing: Connecting PLC-5 systems to custom-built TTL electronic control boards.

• High-Speed Signaling: Triggering fast-acting solid-state devices in packaging or material handling.

• Display Systems: Driving logic-level annunciators and specialized LED display panels.

• Legacy Maintenance: Critical replacement part for existing manufacturing lines utilizing 1771 I/O architecture.