Njoy Ranger 60KR User Manual page 16

4) When the UPS is overload, please remove some loads immediately.
It is recommended to have the total loads connected to the UPS less than
80% of its nominal power capacity to prevent overload for system safety.
5) If the overload time is over acceptable time listed in spec in AC
mode, the UPS will automatically transfer to Bypass mode. After the
overload is resolved, it will return back to AC mode. If the overload time
is over acceptable time listed in spec in Battery mode, the UPS will enter
fault status. At this time, if bypass is enabled, the UPS will power to the
load via bypass. If bypass function is disabled or the input power is not
within bypass acceptable range, it will cut off output entirely.
4. Charge the batteries
1) After the UPS is connected to the mains and turned on in AC
mode, the charger will charge the batteries automatically except in battery
mode, during battery self-test, overload or when battery voltage is high.
2) It's recommended to charge batteries for at least 10 hours before
operation. Otherwise, the backup time may be shorter than expectation.
5. Battery mode operation
1) When the UPS is in Battery mode, the buzzer will sound according
to different battery capacity. If the battery capacity is more than 25%,
the buzzer will beep once every 4 seconds. If the battery voltage drops
to the alarm level, the buzzer will beep once every sec to remind users
that the battery is at low level and the UPS will shut down immediately.
Users could switch off some non-critical loads to disable the shutdown
alarm and prolong the backup time. If there is no more load to be switched
off, you have to prepare shutdown procedure to protect working data or
devices. Otherwise, there is a risk of data loss or load failure.
2) In Battery mode, users can press the Mute button to disable the
buzzer.
3) The backup time of the long-run model depends on the external
battery capacity.
4) The backup time may vary from different operating temperature
and load type.
5) When setting backup time for 16.5 hours (default value from LCD
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