Allen Bradley 1771-OAD PLC 5 Digital AC Output Module

Product Overview

The Allen Bradley 1771-OAD serves as a high-density digital AC output interface for the Universal I/O chassis in PLC-5 systems. This module provides 16 independent outputs to control various 120V AC loads such as motor starters, solenoids, and indicators. We offer this unit as 100% Brand New, original factory stock, ensuring the high-amperage switching capability and backplane compatibility required for mission-critical industrial automation.

Technical Specifications

The 1771-OAD delivers robust power handling across its 16 channels, utilizing zero-crossing switching to minimize electrical noise.

Engineering Advantages

• High-Amperage Switching: This module supports a maximum continuous current of 2 Amps per output. This high rating allows the module to drive larger contactors and actuators directly, often eliminating the need for interposing relays and reducing overall cabinet wiring complexity.

• Zero-Crossing Technology: The 1771-OAD synchronizes output activation with the AC voltage zero-crossing point. This method drastically reduces Electromagnetic Interference (EMI) and inrush current spikes, extending the mechanical life of connected field devices and protecting sensitive nearby electronics.

• Optimized Thermal Management: While handling 2A per point, the module manages heat dissipation across a total module limit of 8A. The 1771 rack-mount design facilitates natural convection cooling, maintaining stable operation even when controlling high-duty cycle loads in industrial enclosures.

• Simplified Field Maintenance: The module utilizes the 1771-WH wiring arm, which detaches from the module housing. This allows for rapid hardware replacement without disconnecting any field-side wiring, ensuring that the 16-point configuration remains intact and error-free during maintenance swaps.

FAQs

• Can the 1771-OAD control DC loads?

  No. The 1771-OAD utilizes Triac switching components specifically designed for AC cycles. Attempting to switch DC loads will prevent the output from turning off, as Triacs require an AC zero-crossing to reset the circuit.

• What is the maximum total current I can pull from the 1771-OAD?

  The module supports a total of 8 Amps across all 16 channels. While individual points handle up to 2 Amps, you must ensure the aggregate load does not exceed the 8A module limit to prevent overheating or internal fuse failure.

• Does this module require a specific wiring arm?

  Yes, the 1771-OAD requires the 1771-WH wiring arm for field-side terminations. This arm provides the secure interface needed to handle the high-current demands of 120V AC applications.

• How does the signal delay affect high-speed applications?

  The zero-crossing turn-on delay (8.3ms at 60Hz) ensures clean activation but introduces a slight latency. For applications requiring microsecond response times, consider DC output modules; however, for standard motor control and industrial sequencing, this delay remains well within acceptable parameters.