Allen-Bradley 1771-OB Digital DC Output Driver Module

The Allen-Bradley 1771-OB functions as a high-reliability digital DC output module within the legendary PLC-5 I/O architecture. This driver module provides eight independent channels designed to interface directly with various DC-powered field devices such as solenoids, motor starters, and indicator lights. By utilizing a sourcing output configuration, the module supplies power from the user-side DC source to the connected load, ensuring a robust electrical interface for heavy-duty industrial applications.

Technical Specifications

Key Operational Characteristics

• High-Current Sourcing Capability: Each of the eight channels supports a continuous current of up to 2A. This high power density allows the module to drive larger inductive loads directly without the immediate need for interposing relays, which simplifies the overall circuit design.
• Universal Chassis Compatibility: The 1771-OB fits into any slot of a 1771 I/O chassis. Consequently, maintenance teams can easily swap modules or expand existing systems without requiring specialized hardware adapters or rack modifications.
• Efficient Signal Processing: The module features a rapid signal response time of approximately 1 millisecond for both activation and deactivation. This low latency ensures that high-speed machinery responds accurately to the PLC’s logic commands.
• Onboard Diagnostic Feedback: Individual status indicators on the front panel display the state of each output channel in real-time. These visual cues significantly reduce the time required for field-side troubleshooting and signal verification during routine maintenance.
• Thermal and Electrical Durability: The design incorporates robust internal circuitry capable of withstanding the heat and electrical surges common in dense control cabinets. This industrial-grade construction ensures reliable performance throughout a long service life in unconditioned environments.