Product Overview

The Allen-Bradley 1768-PA3 is a high-performance power supply unit engineered exclusively for the 1768 CompactLogix™ controller system. This module provides the essential regulated DC backplane power required to operate high-speed 1768 controllers, such as the L43 and L45 series, along with their associated communication and I/O expansion modules. Unlike standard 1769-series supplies, the 1786-PA3 is designed to handle the higher current demands of 1768-based motion control and integrated safety applications.

This power supply is highly versatile, featuring a wide-range input that accepts both AC and DC voltages. It serves as the electrical foundation of the controller bank, ensuring that the processor and local I/O modules receive stabilized power even during fluctuations in the primary line source.

System Integration and Power Distribution

The 1768-PA3 is built to facilitate complex automation architectures while maintaining a compact footprint.

• Broad Input Compatibility: Supports a universal AC input range of 85–265V AC or a 120V nominal DC input (108–132V DC), allowing for global deployment in varied utility environments.

• 1768 Controller Support: Specifically designed to power the 1768-L43, L43S, L45, and L45S processors, which provide integrated Sercos motion and SIL-3 safety capabilities.

• I/O Expansion Capacity: Capable of supporting up to eight 1769 Compact I/O™ modules within a single bank, depending on the specific current draw of the selected modules.

• Efficient Energy Conversion: Features a typical efficiency rating of 75% with a maximum power output capacity of 120VA (AC) or 120W (DC).

• Flexible Installation: Supports standard 35mm DIN rail mounting for rapid assembly or traditional panel mounting for high-vibration environments.

Advanced Diagnostics and Protection

The module includes integrated monitoring tools to ensure system integrity and simplify maintenance.

• Tri-Color LED Status Monitoring: A multi-state LED provides instant visual feedback: Green indicates healthy operation; Red signifies invalid backplane power or a hardware fault; and No Light indicates a loss of input power.

• Integrated Safety Circuitry: Features built-in overcurrent protection including a non-replaceable internal fuse to prevent fire hazards and shield downstream electronics from power surges.

• Isolation and Compliance: Designed with an open-type enclosure and reinforced insulation, meeting stringent industrial standards for electrical separation and noise immunity.

Technical Specifications

• Manufacturer: Allen-Bradley (Rockwell Automation)

• Model Number: 1768-PA3

• Input Voltage (AC): 85V–265V AC (Selectable)

• Input Voltage (DC): 108V–132V DC

• Input Power: 120VA / 120W (Maximum)

• Backplane Output: Dedicated to 1768 System Bus

• Mounting: DIN Rail or Panel Mount

• Operational Temperature: 0°C to 60°C (32°F to 140°F)

• Weight: 0.9 kg (1.98 lbs)

• Dimensions: 13.0 x 14.5 x 3.5 cm