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4
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Operation
4.1 Operation Modes
The UPS is a double-conversion on-line UPS that may operate in the following alternative
modes
：
◆
Normal mode
The rectifier/charger derives power from the AC Mains and supplies DC power to the
inverter while floating and boosting charge the battery simultaneously. Then, the inverter
converts the DC power to AC and supplies to the load.
◆
Battery mode (Stored Energy Mode)
If the AC mains input power fails, the inverter, which obtains power from the battery,
supplies the critical AC load. There is no power interruption to the critical load. The UPS will
automatically return to Normal Mode when AC recovers.
◆
Bypass mode
If the inverter is out of order, or if overload occurs, the static transfer switch will be activated
to transfer the load from the inverter supply to bypass supply without interruption to the critical
load. In the event that the inverter output is not synchronized with the bypass AC source, the
static switch will perform a transfer of the load from the inverter to the bypass with power
interruption to the critical AC load. This is to avoid paralleling of unsynchronized AC sources.
This interruption is programmable but typically set to be less than an electrical cycle e.g. less
than 15ms (50Hz) or less than 13.33ms (60Hz).
◆
Maintenance mode (Manual Bypass)
A manual bypass switch is available to ensure continuity of supply to the critical load when
the UPS is out of order or in repair. This manual bypass switch is fitted for all UPS modules and
bears for equivalent rated load.
◆
Redundancy mode
Based on different demands, The UPS can be set as N+X redundancy mode to increase the
reliability to the load connected.
4.2 Turn on/off UPS
4.2.1
Restart procedure
CAUTION!
