Allen-Bradley 1756-PA72 ControlLogix AC Power Supply

Product Overview

The Allen-Bradley 1756-PA72 is a high-efficiency standard AC power supply module designed for the ControlLogix® 5570 and 5580 chassis platforms. Manufactured by Rockwell Automation, this module mounts directly to the left side of any standard 1756 ControlLogix chassis, regulating and distributing multi-rail DC backplane power to drive automation controllers, specialized communication bridges, and local digital or analog I/O modules.

Core Technical Specifications

Environmental and Operating Thresholds

Engineered to endure the electrical and environmental challenges of industrial control environments, the 1756-PA72 meets the following standard operational parameters:

• Operating Temperature: 0°C to 60°C (32°F to 140°F)
• Storage Temperature: -40°C to 85°C (-40°F to 185°F)
• Relative Humidity: 5% to 95% non-condensing
• Enclosure Style: Open-style, chassis-side mounted configuration
• Regulatory Compliance: CE marked, c-UL-us listed, Class I Division 2 (Zone 2) Hazardous Locations, C-Tick, and KC certifications.

System Integration and Industrial Applications

The 1756-PA72 acts as the primary power lifeline across centralized and distributed ControlLogix control architectures. It is heavily utilized within:

• Heavy Manufacturing Equipment: Supplying clean backplane power to multi-axis motion controllers and industrial communication networks.
• Oil & Gas Refineries: Powering dense control loops, hazardous-area input modules, and SCADA uplink modules.
• Water Treatment Control Skids: Running continuous chemical monitoring loops and localized pump station PLCs.

Operational Characteristics and Functional Advantages

• Multi-Rail DC Power Distribution: Consistently yields exact multi-voltage configurations ($5.1\text{V}$, $3.3\text{V}$, $1.2\text{V}$, and $24\text{V}$ DC) to fulfill the diverse internal hardware requirements of complex logix processing systems.
• Ride-Through and Hold-Up Performance: Features built-in hold-up time mechanics. This capability filters minor line sags and temporary brownouts, ensuring the CPU has adequate time to perform orderly memory flushes or transition into fault-safe states without data corruption.
• Diagnostic Status Indicators: Equipped with a prominent front-panel green LED matrix to provide immediate, real-time confirmation of incoming AC mains supply status and active DC bus output health.
• Direct Chassis Interfacing: Designed for screwless, side-car integration into the 1756 chassis structure, saving valuable DIN-rail footprint inside the primary electrical enclosure.