Allen Bradley 1756-PA72

The Allen Bradley 1756-PA72 power supply module offered by Hanyite is a Rockwell Automation ControlLogix series power supply module. It is primarily used with the 1756 rack, providing 1.2V, 3.3V, 5V, and 24V DC power to the rack backplane. It is installed on the left side of the rack and plugs directly into the backplane. The module's choice will influence the choice of rack type. This module is a standard AC power module manufactured by Allen-Bradley/Rockwell Automation and is part of the ControlLogix power module product line. It has received positive customer feedback.

Q: Allen Bradley 1756-PA72 power module technical specifications

A: Input characteristics: Input voltage is 120/240 V AC, operating voltage range is 85-265 V AC; input power is 100 VA/100 W; input power frequency is 47-63 Hz. It has a wide range of applications. Excellent environmental adaptability and safety.

Output Characteristics: Can provide 1.2V, 3.3V, 5V, and 24V DC power; current capability is 1.5A @ 1.2VDC. Enterprise technicians should pay special attention to this aspect.

Other Specifications: Power consumption rating is 25W within the range of 0 to 60°C, with a power consumption rating of 85.3 BTU/hour; maximum inrush current is 20A; maximum current is 15A, with a maximum transformer load of 100VA; continuous voltage isolation is 250V; reinforced insulation type has been tested to 3500VDC for 60 seconds. Enterprise operators are welcome to contact Hanyite personnel at any time.

Q: What are common fault types and symptoms?

A: Abnormal power output

This is manifested by abnormal module indicators (such as no power light or a steady alarm light), which may cause downstream equipment to shut down or restart. Check that the input voltage is within the rated range and that the output is not overloaded or short-circuited.

Communication Interruption

If the module loses communication with the main controller, it may be due to a loose communication interface or a faulty optical isolation circuit. Diagnostics can be performed via the RS-232 interface (25-pin male D-type connector) at 9600 baud. Technicians should pay special attention to this aspect.

Diagnostic Alarms

The module has built-in fault detection circuitry that continuously monitors the power rails, regulators, and internal buses. If a transient fault occurs, the fault code can be read using the Diagread diagnostic tool; for permanent faults, the hardware majority voting circuit status must be checked. Enterprise technicians are welcome to contact Hanyite personnel at any time.

Troubleshooting and Troubleshooting Steps

1. Preliminary Inspection

Confirm that the module is securely installed in the physical slot and that the dual power rails are properly connected.

Measure the input voltage stability to rule out power grid fluctuations or loose connections.

2. Diagnostic Tool Application

Connect to the Diagread software via the Triconex diagnostic interface (RS-232) to read logs of memory access and communication bus status.

If "Communication Processor Fault" is displayed, check the operating status of the Motorola MPC860 processor (32-bit, 50MHz) and the integrity of the Flash ROM data.

3. Hardware Replacement and Fault-Tolerant Operation

If a permanent fault is diagnosed, online module replacement is supported, and the system will automatically switch to fault-tolerant mode (relying on fault detection circuitry and redundant design).

Before replacement, configuration data must be backed up to ensure the new module firmware version is compatible with the original system. Operators can contact Hanyite at any time.

Q: What kind of after-sales service does Hanyite provide?

A: We offer a 24/7 technical hotline, free parts replacement service within the two-year warranty period, and customized program development support. Please feel free to contact us with any questions. For purchasing, please identify Hanyite in China. We provide 24-hour consulting services.