GE LP 33 Series Operating Manual page 16

Automatic bypass operation
In VFI (Voltage Frequency
operation mode, the load is permanently
supplied by the inverter but, in case of trouble
on the inverter, or when overload or short-
circuit on the output occur, if the mains
voltage do not exceed the admitted tolerances,
the load is instantly transferred to the mains
through the automatic
advantage of the higher short circuit power.
When the inverter recovers, the load will be re-transferred automatically to the inverter.
In case of Parallel System
Each unit has its own bypass.
All the bypasses in the system work together, their control being managed in the same manner by
all units.
The units are continuously exchanging information before taking such decision.
In case the inverter of one unit fails, its bypass remains operating.
It is excluded only if the unit is separated from the common bus by opening its output switch Q1.
Mains recovery operation
As soon as the mains recovers, the rectifier
starts up automatically supplying the inverter
and the battery-charger
battery.
In case the inverter has been shut down
following a complete discharge of the battery,
when the mains recovers the system start up
automatically.
When the energy stored in the battery is sufficient to ensure a minimum time of operation with the
actual load, in case of a future mains failure, the load will be retransfered to inverter (if selected VFI
Mode).
In case of Parallel System
When the AC input power recovers, the rectifiers will start up sequentially according to their
number in the Parallel System in order to avoid an initial inrush current.
The inverters will start up automatically, but only when the battery has recharged enough for a
minimum runtime with the present load.
When enough inverters to supply the load have been restarted, the load will be transferred from the
automatic bypass back to the inverter bus-bars.
Modifications reserved
OPM_LPS_33E_60K_M12_2GB_V010.doc
Independent)
bypass, taking
recharges the
Fig. 4.2-3 Energy flow in automatic bypass operation
Fig. 4.2-4 Energy flow at mains recovery operation
Operating Manual LP 33 Series 60-80-100-120 kVA / S2
Page 16/103