Hardware Installation and Maintenance Guide, Version 11.50.3 - Requirements for replacing a power supply

If you plan to replace a power supply, keep the following requirements in mind.

You must have a replacement power supply (power-fan canister) that is supported for your controller shelf or drive shelf model.
You have an ESD wristband, or you have taken other antistatic precautions.
You can replace a power supply (power-fan canister) while your storage array is powered on and performing host I/O operations, as long as the following conditions are true:
- The second power supply (power-fan canister) in the shelf has an Optimal status.
- The OK to remove field in the Details area of the Recovery Guru in ThinkSystem System Manager displays Yes, indicating that it is safe to remove this component.
  Attention: If the second power supply (power-fan canister) in the shelf does not have Optimal status or if the Recovery Guru indicates that it is not OK to remove the power-fan canister, contact technical support.