I recently experienced a power outage for just a few seconds, and despite my PC being connected to a UPS, it shut down. I've checked the UPS and it seemed fine, with the battery life above 80%. I even tested it by unplugging the UPS while my PC was connected, and the PC stayed on without any issues. This is the first power outage since I bought the UPS, and I usually only run it at 65% load. Should I be worried that the UPS isn't properly protecting my PC, and what could have caused it to shut off?
4 Answers
Double-check that any UPS software isn’t set to shut down the PC when it’s on battery. You mentioned your battery is at 90%, so it shouldn’t be a low charge issue.
Is your UPS plugged into the right outlets? Make sure it's using the ones labeled "MAIN" for battery backup. If it's on the "Non-critical" side, it only provides surge protection, not battery support.
I’ve had similar issues with UPS during very brief outages. Some units can’t handle quick power flickers because of a delay in switching over to battery, which can make it seem like the power just cut off.
Sometimes, UPS units have a delay when switching to battery power. If the power interruption is too quick, the UPS might not engage fast enough, leading to a shutdown.

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