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OTHER FEATURES
BACK-FEED PROTECTION
The UPS has an internal protection against back-feed. This protection acts by means of a sensing circuit which
turns off the inverter if a fault within the static switch is detected. In this condition, to avoid interrupting the supply to
the connected load, the UPS switches to bypass line.
If the bypass is not available, the connected load is switched off.
To avoid stopping the inverter, a dry contact can be configured to drive a disconnection device. This device must be
installed upstream of the bypass input to the UPS, in this case when a back-feed fault occurs, the system opens the
external disconnection device (for further information, refer to the configuration software manual).
The label supplied with the UPS must be affixed to all isolators installed in the electrical system upstream
of the UPS.
Latch-on-bypass function
The UPS has an internal device (redundant bypass power supply) which activates the bypass automatically when a
major failure occurs within the UPS; thus, keeping the load powered without any internal protection and without any
limitation to the power supplied to the load.
WARNING:
Under these emergency conditions, any disturbance present at the input supply will affect the load.
Power Walk-In
The Power Walk-In function can be activated through the configuration software. This function enables, upon
reconnection to the power supply (following a mains supply failure), a progressive absorption of power from the
incoming supply, in order to avoid stressing (due to the inrush current) a generator or a weak power supply which is
potentially installed upstream. The duration of the Power Walk-In mode can be set between 1 to 120 seconds. As
default configuration the Power Walk-In is disabled, however the maximum input current is limited. During this mode
the required power is partially taken from the batteries and partially from the power supply whilst maintaining a
sinusoidal power ramp-up. The battery charger is only switched on once the transition is complete.
