Smart-UPS 1500 turned off output power

[Anonymous user]

Hi,

I have Smart-UPS 1500 (SMT1500I) with Firmware Revision UPS 09.3 (ID18). AP9630 v6.5.0.

All devices connected to the UPS have been rebooted due to a power failure. But why did it happen? There is no ethernet access to the UPS interface from servers/devices. UPS is connected only via USB cable and monitored with apcupsd service.

08/06/2021 12:15:29 apc Web user 'xyz' logged in from xyz. 0x0015
08/06/2021 05:07:08 Device UPS: The power for switched outlet group 1, Outlet Group 1, is now turned on. 0x0134
08/06/2021 05:07:07 Device UPS: The power for switched outlet group 1, Outlet Group 1, is now turned off. 0x0135
08/06/2021 05:07:07 Device UPS: The power for the main outlet group, UPS Outlets, is now turned on. 0x0134
08/06/2021 05:07:06 Device UPS: The output power is now turned on. 0x0113
08/06/2021 05:07:05 Device UPS: The output power is turned off. 0x0114
08/06/2021 05:07:05 Device UPS: The graceful shutdown period has ended. 0x014F
08/06/2021 05:07:05 Device UPS: Switched outlet group 1, Outlet Group 1, has been commanded to shutdown, sequenced. 0x0174
08/06/2021 05:07:05 Device UPS: Main outlet group, UPS Outlets, has been commanded to shutdown with on delay. 0x0174
08/06/2021 05:07:05 Device UPS: The power for the main outlet group, UPS Outlets, is now turned off. 0x0135
08/05/2021 12:17:26 System NTP update successful. 0x004A

Could you please help understand why?

Martin