AEG Protect B. 750 PRO Operating Instructions Manual page 10

Under continuous mains undervoltage or overvoltage within
defined ranges, the automatic voltage regulation (AVR) provides
additional stabilisation of the electrical load voltage. Voltage
fluctuations of the public mains are thus damped to a level
acceptable for the electrical loads. This occurs without accessing
the internal power reserves, which in turn has a positive effect on
battery availability.
Mains
Mains
AVR
filter
Load
~
~
Inverter
Rectifier
Battery
Block diagram of UPS Protect B. PRO
If a mains failure occurs, the switch device is activated. At this
point, the inverter takes over the supply of power to the
EN
connected electrical loads to avoid the risk of data loss or
electrical load damage. The Protect B. PRO continues to provide
power until the battery is discharged or until your IT system is
properly shut down and switched off.
This autonomy time is largely dependent on the connected
electrical load value. When the mains supply exhibits normal
values again, the UPS switches the electrical load back to the
mains. The battery charge rectifier then recharges the battery.
If a mains failure occurs, the mains input into the device is dis-
connected via both poles for safety reasons (VDE, German
Association for Electrical, Electronic & Information
Technologies). This securely prevents feeding back into the
mains and live voltage on the poles of the power plug.
Additional measures also ensure effective protection of the
data/network interface.
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