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smoothly in order to obtain the greatest efficiency. Irregularities can be detected in less
than a second and the on-line mode can be reactivated immediately. Switching back to
online mode occurs when the input voltage exceeds ±10% (or ±15% selectable), when
the input frequency exceeds ±3Hz, or when no input line is available.
Although high efficiency is standard , the defa ult oper ation is t he on-line mode. From
the LCD display panel, Bypass can be activated as required or On-line operation can be
run permanently if preferred.
2.3 Auto-Restart
In the event that a po wer fail ure las ts longer than the UPS backup time, the UPS will
shut down. Upon power restoration, the UPS will restart automatically in On-Line mode,
which includes output power being restored to the load and the start of battery recharge.
2.4 Free Run Mode
Free run mode is a mode of operation in which the UPS outputs a pre-set frequency (50
or 60 Hz) regardless of the input frequency. The UPS operates in free run mode when
the input frequency is outside of the selected input fr eque nc y ra nge. W he n start in g the
UPS, the targeted frequency is 50 or 60 Hz ±0.25 Hz.
2.5 Diagnostic Tests
When the UPS is started, a diagnostic test is executed automatically that checks the
electronics and battery, and reports any problems on the LCD display.
The advanced battery management syst em monitors the performance of the battery and
will indicate if battery replacement is required. The battery management system tests
the battery every 30 days of normal mode operation. A battery discharge test is
performed and reports any problems on the LCD display.
Except during the first 24 hours after s tartup while the UPS is in c harging mode,
diagnostic tests can be performed manually from the front panel when required.