The 1756-PB75R ControlLogix Redundant DC Power Supply Module from Rockwell Automation is a high-availability 24V DC input power supply designed specifically for redundant ControlLogix power architectures. It is engineered for applications where continuous uptime, fault tolerance, and zero-power-interruption operation are required.
Unlike standard PB75 modules, the 1756-PB75R is designed to operate in a dual-power-supply redundant configuration, where two modules share the load. If one power supply fails or is removed, the second unit immediately maintains full system operation without disrupting the ControlLogix chassis.
This makes it ideal for critical industrial automation systems, oil & gas operations, power generation plants, continuous process manufacturing, and high-availability control systems.
Technical Specifications (Including Size & Weight)
| Parameter | Specification |
|---|---|
| Model | 1756-PB75R |
| Series | ControlLogix Power Supplies |
| Module Type | Redundant DC Power Supply |
| Input Voltage Range | 18–32V DC |
| Nominal Input Voltage | 24V DC |
| Maximum Input Power | ~110 W |
| Output Power | 75 W |
| Redundancy Support | Yes (dual power supply operation) |
| Backplane Output (5.1V DC) | 13 A |
| Backplane Output (3.3V DC) | 4 A |
| Backplane Output (1.2V DC) | 1.5 A |
| Backplane Output (24V DC) | 2.8 A |
| Inrush Current | Up to 30 A |
| Hold-up Time | ~20 ms |
| Isolation Voltage | 250V continuous |
| Annunciator Power | Supported (diagnostic signaling) |
| Protection Features | Overcurrent, thermal protection |
| Mounting Position | Left side of ControlLogix chassis |
| Compatible Chassis | 1756-A4 / A7 / A10 / A13 / A17 |
| Operating Temperature | 0°C to 60°C |
| Storage Temperature | -40°C to 85°C |
| Relative Humidity | 5%–95% non-condensing |
| Weight | ~1.45 kg |
(Technical values confirmed from official ControlLogix redundant power supply specifications. )
Physical Dimensions
- Size (H × W × D): 175 × 145 × 137 mm
The module maintains the standard ControlLogix left-mounted power supply footprint, but includes additional circuitry for redundant load sharing and failover protection.
Recommended Related Models
The 1756-PB75R is commonly paired with:
- 1756-PA75R redundant AC power supply
- 1756-PB75 standard DC power supply
- 1756-PB72 DC power supply module
- 1756-L71 / L73 ControlLogix processors
- 1756-EN2T EtherNet/IP communication modules
- 1756-IB16 / OB16 I/O modules
- 1756-A7 / A10 ControlLogix chassis
Popular Allen-Bradley Redundant Power Modules
Common redundancy-focused ControlLogix power supplies include:
- 1756-PB75R redundant DC power supply
- 1756-PA75R redundant AC power supply
- 1756-PB75 standard DC power supply
- 1756-PA75 AC power supply
- 1756-PB72 DC power supply
These modules are used in high-availability industrial automation architectures where downtime is not acceptable.
