APC UPS's "Comm Event: To Pwr Off Press And Hold Pwr Button" after the electricity suddenly fluctuated for around 1 second

Electricity suddenly fluctuated for around 1 second.

 

Severs in normal.

APC UPS (Smart-UPS SRT 3000VA) showed "Comm Event: To Pwr Off Press And Hold Pwr Button".

 

Pressed & held the Power button, not power off the UPS, however.

Solved it by all cables disabled - power supply cables & usb console cable.

 

Then, turned it off & on back.

 

The UPS was back to normal.

 

1.

2. "Comm Event: To Pwr Off Press And Hold Pwr Button"

 

 

3. "No Logs Present Press Esc to go back" 

 

4. Disconnected all cables, which were USB Console cable & Power Supply cables, connecting to the UPS. Then, it (auto) changed to warning mode

 

 

5. "Turn Off Immediately", then "  Internal Power Off"

 

6. Powered it back on

 

7. Back to normal

Update