Local PSU Failure Indicators
If two PSUs are fitted to provide redundancy and there is a single PSU failure, a loud, continuous,
audible alarm sound will be heard coming from the appliance. The alarm can be switched off by
pressing the red button located to the right of the PSUs. This button is indicated on the image
shown below.
Figure 4.2. The Alarm Reset Button
In normal operation there is a green LED light that is illuminated on the back of each PSU. This
LED will not be illuminated if its PSU has failed. This LED is indicated on the image shown below.
Figure 4.3. The PSU Status LED
Swapping a PSU
To swap a failed PSU:
1.
Switch off the power source to the faulty PSU. This may be done by simply unplugging the
power cable from a wall socket.
2.
Remove the power supply cord from the PSU.
3.
Firmly put two fingers around the PSU handle while using another finger to push the
locking switch horizontally to one side. This is shown in the image below.
4.
Once the locking switch is moved to the side and the lock disengaged, gently pull out the
failed PSU until it is clear of the appliance and place it to one side.
5.
After grasping the replacement PSU's handle with two fingers, gently slide it into the now
empty PSU slot until it clicks into place. The locking switch need not be pushed. Inward
Chapter 4: Product Maintenance
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