Product Introduction
The Allen-Bradley 1756-PA75 is a standard AC power supply engineered for ControlLogix automation platforms. This Industrial Automation Module converts external 85-265VAC line power into the regulated DC voltages that ControlLogix backplanes require, ensuring stable operation of all connected I/O, communication, and controller modules.
Designed for the leftmost slot of any 1756 chassis, the 1756-PA75 delivers 75W of output power at 0 to +60 °C, with triple-output current capacity: 4A at 3.3VDC, 13A at 5.1VDC, and 2.8A at 24VDC. Its wide input range and robust construction make it a dependable choice for demanding industrial environments.
Technical Specifications
The following table lists the key specifications of the Allen-Bradley 1756-PA75:
| Parameter |
Value |
| Manufacturer |
Rockwell Automation / Allen-Bradley |
| Series |
ControlLogix |
| Module Type |
Standard DC Power Supply |
| Input Voltage Range |
85-265VAC |
| Nominal Input Voltage |
120/240VAC |
| Input Frequency |
47-63 Hz |
| Input Power |
100 Watts |
| Output Power |
75 Watts at 60 °C |
| Current Capacity |
4A at 3.3VDC; 13A at 5.1VDC; 2.8A at 24VDC |
| Isolation Voltage |
250 Volts Continuous |
| Max Inrush Current |
30 Amperes |
| Hold-Up Time |
2 cycles @ 85VAC, 60 Hz; 6 cycles @ 120VAC, 60 Hz; 20 cycles @ 220VAC, 60 Hz |
| Operating Temperature |
0 to +60 °C (32 to 140 °F) |
| Weight |
0.95 kg (2.10 lb) |
| Dimensions (H x W x D) |
14.0 x 11.2 x 14.5 cm (5.51 x 4.41 x 5.71 in.) |
| Chassis Compatibility |
1756-A4/A/B/C, 1756-A7/A/B/C, 1756-A10/A/B/C, 1756-A13/A/B/C, 1756-A17/A/B/C |
| UNSPSC |
32151706 |
| Enclosure |
None |
Industry Applications
The 1756-PA75 is ideal for applications requiring reliable backplane power in discrete and process control systems. Common uses include:
- Manufacturing assembly lines where ControlLogix controllers manage robotic cells and conveyors.
- Oil and gas facilities that rely on redundant PLC architectures for critical safety interlocks.
- Water treatment plants using ControlLogix for SCADA and batch processing.
With its wide input range, the 1756-PA75 adapts to global power grids, reducing inventory complexity for OEMs and system integrators.
Installation & Setup Guidance
Mount the 1756-PA75 in the dedicated power supply slot at the leftmost position of the 1756 chassis. Ensure the chassis is properly grounded and that the input power source matches the rated voltage and frequency. The power supply requires hardware configuration before operation—refer to the ControlLogix installation manual for jumper or switch settings. Always disconnect power before installing or removing the module.
Maintenance & Reliability
Regularly inspect the 1756-PA75 for dust accumulation and ensure adequate airflow around the chassis. The unit has a non-replaceable fuse that protects against short-circuit hazards; if the fuse blows, replace the entire power supply. Operating within the specified temperature range (0-60 °C) extends service life and maintains output accuracy. Periodic checks of input voltage and output currents help detect early signs of degradation.
Compatibility & Integration
The 1756-PA75 is fully compatible with all ControlLogix chassis models listed above, including Series A, B, and C revisions. It provides backplane power to any combination of ControlLogix modules, including controllers, I/O, and communication interfaces. Ensure the total backplane power consumption does not exceed the 75W rating.
Selection Guide & Purchasing Advice
Before purchasing, verify your chassis model and required power budget. The 1756-PA75 is a standard AC power supply; if your control panel uses DC power, consider the DC version (1756-PB75). For reliable sourcing, PLC Source PRO offers genuine Allen-Bradley 1756-PA75 modules with fast worldwide shipping.