inform ETR EVO Series, Installation And Operating Manual

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ETR EVO UPS User Manual (Ver. 1.0) Page 30
runs in Online Operation, then it can not switch to Bypass Operation even if a fault occurs. If the
batteries and the inverter are suitable to supply the loads, then UPS switches to Battery Operation.
Bypass Operation voltage tolerance limit can be adjusted in certain ranges, depending on the
customer’s request, in the factory as well as at the field by Technical Service Personnel.
To return to Bypass Operation; the mains voltage should turn back to +5V above of lower limit, -5V
down of upper limit of bypass limits. Default settings are 203V – 237V for 220V UPS.
5.2. Online Operation
Energy is drawn from the mains input. Loads are supplied through the rectifier and the inverter. The
AC voltage at the input is converted to a DC voltage by the rectifier. The inverter converts this DC
voltage to an AC voltage with a stable sinusoidal waveform, amplitude and frequency. Output voltage
and frequency can be set via front panel. Output voltage is sinusoidal and has a regulated amplitude
and frequency. It is independent from the input voltage. The loads are not affected by the negativities
of the mains.
If the mains voltage and frequency are in certain range, Online Operation is possible. For the mains
limits for Online Operation, please see
Appendix-3 Technical Specifications .
The upper limit of mains voltage is independent from the load percentage
and it is 270V. UPS switches
to Battery Operation mode when the mains is over 270V. The mains is required to decrease below
260V for UPS to return Online Operation.
Online Operation Conditions;

In case Online Operation is set as operation mode of UPS, the mains is within the limits and/or if
there is no abnormal condition (overheat, overload, failure…etc.) UPS operates in Online
Operation. Except for failures, as soon as the abnormal conditions are eliminated, UPS switches
to Online Operation automatically.

In case Bypass Operation is set as operation mode of UPS and the voltage and frequency is out of
the bypass limits but within the rectifier limits, UPS swithes to Online Operation.
5.3. Battery Operation
In this operation, energy is drawn from the batteries. The loads are supplied via inverter. Output
voltage is sinusoidal and has a regulated amplitude and frequency. It is independent from the battery
voltage. Battery voltage should be in acceptable limits and the inverter should be enabled for the
UPS to operate in this mode.
UPS operates in Battery Operation in the following cases:

While UPS is operationg in Onlne Operation; if frequency/waveform/rms value of mains voltage
go beyond the rectifier limits,

While UPS is operationg in Bypass Operation, if frequency/waveform/rms value of mains voltage
go beyond the rectifier and Bypass limits,

Inverter “ENABLE”, Rectifier “DISABLE” is selected through the front panel.