QLS250, QLS450, QLS650, and QLS800

The appliances have a redundant Power Supply Unit (PSU). They support AC PSUs.

If necessary, you can replace a PSU. Note that all PSUs on an appliance must be of the same type (AC).

Warning: To protect yourself and the appliance PSUs from electrostatic discharge, make sure that you are electromagnetically grounded before you install, uninstall, or replace a PSU. We recommend that you use an ESD grounding wrist strap. Connect the grounding plug on the wrist strap to the appliance grounding point.

Warning - All work related to the AC power must be performed by trained and certified service personnel only.

QLS250 Rear Panel

QLS450, QLS650, and QLS800 Rear Panel

Legend

Item	Description
1	LED indicator for each PSU Off - No power supply cable is connected to any of the PSUs in the system Green - System is on Blinking green - Power supply cables are connected to all PSUs, but system is off Amber - No power supply cable is connected to the PSU, but other PSUs in the system are connected to a power supply cable Blinking amber - Warning that a hardware issue (high temperature, high power, high current, slow fan) might lead to an issue with the PSU Blinking fast green - PSU undergoing Firmware update
2	Restraint strip slot
3	Extractor handle
4	ESD grounding point
5	Alarm off button for PSUs
6	Release lever
7	QLS250 - Two AC PSUs QLS450, QLS650, and QLS800 - Three AC PSUs

Removing an AC Power Supply Unit

Before you remove a Power Supply Unit, we recommend that you make sure that:

• In QLS250 - A second AC power supply is installed and connected to a working power source.

• In QLS450, QLS650, and QLS800 - Two other AC power supplies are installed and connected to a working power source.

  Or

• The appliance is shut down.

To remove an AC Power Supply Unit:

1. Remove the power supply cable from the AC PSU.

2. If the alarm sounds, press the Alarm Off button to the right of the AC PSU.

3. Press and hold down the PSU release lever.

   

4. While holding the PSU release lever, pull the extraction handle to remove the AC PSU.

Note - Remove the PSU only with the extraction handle to prevent any possible damage.

Installing an AC Power Supply Unit

To install a replacement AC Power Supply Unit:

1. Insert the AC PSU into the power supply slot.

2. Push in the AC PSU until the release lever clicks.

   

3. Insert the AC power supply cable into the power supply socket.

4. Make sure that the power LED on the AC PSU is lit up.

Installing the AC Power Supply Cable Restraint

Use the power supply cable restraint to prevent accidental removal of the power supply cable.

Legend

Item	Description
1	Restraint anchor
2	Cable loop
3	Restraint strip tab
4	Restraint strip

Legend

Item	Description
1	Restraint strip slot
2	Power supply socket

To install the AC power supply cable restraint:

1. If a power supply cable is connected to the power supply socket, disconnect it.

2. Locate the restraint strip slot above the power supply socket.

3. Make sure that the cable loop on the restraint faces the power supply socket.

4. Insert the restraint strip anchor into the slot until it fastens and locks.

5. Connect the power supply cable to the power supply socket.

6. Pull the restraint tab to the side to move the cable loop on the restraint strip.

7. Move the cable loop until you can position it around the power supply cable.

8. Insert the open side of the cable loop into the loop slot until it fits tightly against the power supply cable.

9. Make sure the cable loop is secured and the power supply cable cannot be removed.

Restraint strip anchor inserted into the slot

Cable loop secured around the power supply cable