An uninterruptible power supply (UPS) system provides temporary power to critical devices when the main source of power goes out. The battery of the UPS provides this temporary power, which is enough to allow users to save important files and shut down their devices properly.
The UPS typically charges the battery when the main power source comes back.
But, there may be some rare instances when the UPS would give out a notice showing the battery voltage exceeds the battery voltage rating. The issue may be due to a defective battery, which will require the replacement of the battery. It may also be that the unit is defective, which means it should be sent back to the manufacturer if it is still under warranty. Another possible reason for the warning to come is a glitch in the system.
To check the reason behind the issue, it is necessary to perform a self-test on the unit. If no issues are noted after the self-test, the next thing to do is to reboot the UPS using the Brain Dead procedure.
The Brain Dead procedure in rebooting a UPS is a reset of the microprocessor without resetting any preferences saved by the user. The Brain Dead procedure depends on the type of UPS involved:
For SU, SUM, SUA and SURT unit, it will be necessary to turn off and unplug the unit. The OFF button should be pressed and held until the LEDs emit a flash and a click can be heard from the UPS. After this, the UPS can be plugged into an outlet and turned on.
For SMX, SMC and SMT units, the UPS is turned off and unplugged before the battery is disconnected. At this point a click should be heard before the battery is reconnected. The UPS can be plugged into an outlet and turned on.
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