GE LP 33 Manuale Utente

Modifications reserved

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OPM_LPS_3UO_30K_40K_0US_V010.doc

Operating Manual LP 33 Series 30 & 40 kVA

Manual bypass operation

The manual bypass circuit consisting of Q1 and

Q2 manual switches, permits the transfer of the

load directly to the mains without interruption,
leaving the UPS galvanically separated from the

output load.

This type of operation is normally used when the

UPS system must be completely turned off for
maintenance or reparation.

Fig. 3.2-5 Energy flow in manual bypass operation

Mains failure operation

In the event of a mains power failure, the
rectifier and the battery-charger turn OFF,

while the inverter continues to supply the load
without interruption using the energy stored in
the battery.

During the battery discharge, the LCD screen

displays the remaining autonomy, based on the
battery capacity and the applied load.

Fig. 3.2-6 Energy flow during mains failure operation

In the event of an extended mains failure, before the battery is fully discharged, the alarm “stop

operation” warns the user that the UPS will start the shutdown procedures when the indicated time
expired (normally 3 minutes).

In case of parallel system

With parallel system for power capacity:

• With the bypass mains power available as the warning “battery low” occurs on one unit, after

timeout (selectable) the load is transferred to mains.

• With missing bypass mains power as the warning occurs on one unit, the system starts the

timeout (selectable) of “Stop operation” and then the output load shuts down.

With redundant parallel system:

• As the warning battery low occurs on one unit unnecessary to support the present load, after

timeout (selectable) this unit shuts down and the load is shared between the other units.
As the warning occurs on one unit necessary to support the present load, the system starts the

timeout (selectable) of “stop operation” and then the output load shuts down.