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(2) Upon failure of commercial power
When a fault or an outage occurs in the commercial power source, the rectifier and
charger cease operating while inverter operation continues, now using the batteries
as a DC source, to ensure stable power supply to the loads without even a
momentary power dropout. At this time, the battery operation beeper sounds and
the green INPUT indicator lamp blinks. Pressing CLEAR silences the beeper.
Also, because each UPS Unit has its own CLEAR button, it must be pressed on
every unit.
Power supply route upon failure of commercial power
Indicator status upon failure of commercial power
(3) When battery voltage becomes low
If the commercial power abnormality or outage persists, the BATT.LOW (low battery
voltage) indicator on the panel lights when battery voltage falls below 1.85 volts per
cell.
(4) Upon recovery of commercial power
When normal commercial power recovers, rectifier and charger operations resume
automatically, returning to the normal operating state described in (1).
(5) Extended power outage
If a power outage persists and the battery voltage reaches the final discharge level,
a protective circuit shuts off the inverter to prevent overdischarging the batteries.
When normal commercial power recovers after the inverter has been stopped
automatically, operation is automatically resumed, returning to the normal
operating state described in (1).
Rectifier
(Converter)
Inverter
Battery
Charger
AC power
source
(commercial)
Output
Output
Selector
switch
Note: The on/off state of the F.T. LED
and LOAD LEVEL LED depends
on the load level.
