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UPS for 400 Vac Grid, User Guide, doc. rev. 4
4.
Overview of Operating Modes
The UPS functions to supply AC electrical power to your load.
The UPS has five possible modes of operation:
1.
Normal mode
2.
Battery mode
3.
Bypass mode
4.
ECO mode
5.
Maintenance Bypass mode
The following sections provide a short summary of the function and purpose of each mode.
4.1.
Normal mode
The UPS is almost always in normal operation mode. The load receives its power from the
inverters that supply stabilized voltage, protected from spikes and irregularities from the AC
input. The rectifier feeds the inverter, and supplies DC power to charge the battery.
4.2.
Battery mode
During battery operation, the load continues to receive power from the inverters, but the DC
input to the inverter is taken from the batteries, instead of from the rectifier. Battery mode is used
whenever the grid power is faulty.
The duration of the battery operation is determined by the load demand and the battery capacity.
4.3.
Bypass mode
During bypass operation, the load receives power directly from the bypass AC input via the static
switch.
Whenever the inverters cannot provide power to the load, either due to an overload or a short-
circuit in the load, the load is automatically moved to the bypass AC input. The load is
automatically returned to the inverter when the problem has been corrected.
4.4.
ECO mode
ECO mode is an alternative mode of UPS operation.
In ECO mode, the UPS's normal state is bypass mode. In ECO mode the mains power directly
feeds the load via the static switch, while powering the rectifier and keeping the inverter in a
standby state. Meanwhile, the rectifier continues to charge the battery during ECO mode.
When the UPS in ECO mode detects an irregularity in the bypass input, the UPS transfers the load
to the inverter, and feeds the load conditioned power as in a "normal" UPS.
