Remove Or Replace A Redundant Power Supply; Remove Or Replace A Chassis Adapter - Allen-Bradley 1756-PA75R Installation Instructions Manual

Remove or Replace a Redundant Power Supply

WARNING: EXPLOSION HAZARD
Remove or replace power supplies only when backplane and power supply power are removed or the area is known to be nonhazardous. Removal or replacement
of a power supply in a hazardous area can cause an electric arc across the contacts if backplane power is still applied.
IMPORTANT You can replace one redundant power supply while the other supply is operating in nonredundant mode without any affect on chassis operation.
If you must only replace a redundant power supply cable, we recommend that you do this replacement when the conditions permit the removal of all
system power.
Remove a Redundant Power Supply
Follow these steps to remove the redundant power supply.
1. Turn the redundant power supply OFF.
2. Disconnect the line power source voltage from the redundant power supply and annunciator.
3. Remove the wiring terminal blocks.
4. Unscrew and disconnect the 1756-CPR2, 1756-CPR2D, or 1756-CPR2U cable at the power supply.
5. Remove the bottom mounting screws.
6. Loosen the top mounting screws and slide the supply up and off the mounting screws.
Replace a Redundant Power Supply
Follow these steps to replace a redundant power supply.
1. Slide the redundant power supply over the top mounting screws and tighten them.
2. Install the bottom mounting screws.
3. Reconnect the 1756-CPR2, 1756-CPR2D, or 1756-CPR2U cable at the power supply.
4. Install the wiring terminal blocks.
5. Connect the line power source voltage to the redundant power supply and annunciator.
6. Turn the redundant power supply ON.
When you turn ON the replacement redundant power supply, the connected chassis automatically draws power from the redundant power
supplies.

Remove or Replace a Chassis Adapter

Use this information to remove or replace a chassis adapter.
Remove a Chassis Adapter
Follow these steps to remove a chassis adapter.
1. Turn the redundant power supplies OFF.
2. Disconnect the power cable at the chassis adapter.
3. Push the top and bottom locking tabs on the chassis adapter to the side and pull the module off the chassis.
Replace a Chassis Adapter
1. Align the circuit board of the adapter with the card guides on the left side of the chassis.
2. Slide the adapter back until it is flush with the front of the chassis.
Rockwell Automation Publication 1756-IN620D-EN-P - October 2018
ControlLogix Redundant Power Supply
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