1756-CPR Power Supply Cable | Allen-Bradley

Configured for redundant power distribution in ControlLogix chassis systems, the Allen-Bradley 1756-CPR (1756-CPR Power Supply Cable) provides direct physical/electrical execution of power interconnects between 1756 series power supply units.

Hardware Specifications

PLC and Drives: Backplane Bus Communication Velocity

The 1756-CPR cable assembly facilitates the synchronized operation of redundant power supplies within the 1756 ControlLogix architecture. The cable manages the primary-to-secondary power handshake, ensuring that the backplane bus communication velocity remains stable during power failover events. Electrical continuity must be maintained across the dual-connector interface to prevent transient voltage drops that could disrupt the backplane power rail, potentially affecting the deterministic execution of the control processor.

Frequently Asked Questions (FAQ)

Q: Is this cable compatible with all ControlLogix power supply modules?

A: The 1756-CPR is specifically designed for 1756 series redundant power supply configurations. Verify the specific revision of the power supply modules to ensure pinout compatibility, as incorrect cable usage may lead to improper power sharing between units.

Q: Can this cable be used for non-redundant power configurations?

A: No. The cable is designed strictly for the synchronization and power management of redundant supply sets. Utilizing this cable in a single-supply configuration does not provide any functional benefit and may leave open connectors exposed to potential short-circuit hazards.

Field Installation Guidelines

• Connector Seating: Ensure both connectors are fully inserted into their respective receptacles on the power supply modules. The locking mechanism must be engaged to prevent accidental disconnection due to chassis vibration.

• Cable Routing: Route the cable through the designated chassis cable management channels. Do not bundle the 1756-CPR with high-voltage AC input lines, as induced electromagnetic noise can potentially interfere with the DC output regulation logic.

• Redundancy Testing: After installation, verify the status indicators on both power supply modules to confirm that the redundant handshake has been established. If the fault indicator remains illuminated, inspect the cable for continuity and ensure the connectors are seated flush against the modules.