User manual

3-3-1. Normal operation, ()
With the mains present, the rectifier transforms the AC input voltage into DC raising the DC voltage to a
suitable level for supplying the inverter and to charge the batteries. The inverter deals with transforming the
voltage of the DC bus into AC, providing a sine wave alternating output, stabilized in voltage and frequency to
supply the loads connected to the output (figures 17 and 18).
3-3-2. Operation with mains failure, ()
In the event of mains failure or should a micro cut occur, the group of batteries supplies the power needed
to supply the inverter. The inverter continues working normally without appreciating the lack of mains and
the back-up time of the device depends only on the capacity of the group of batteries (figures 17 and 18).
When the battery voltage reaches end of back-up time, the control blocks the output as protection against a
deep battery discharge. When the mains returns and following the first seconds of analysis, the UPS
operates once more as in section «Normal operation».
3-3-3. Operation with inverter not active, ()
The inverter is inactive due to the existence of alarm conditions such as overloads, overheating, end of
back-up time, etc… In that cases the rectifier continues charging the batteries to maintain their optimal
charge state.
The inverter is also inactive if the unit has not been started up with the keyboard. In that case, the rectifier
will be inactive.
In all these cases the output voltage of the UPS is supplied by the emergency bypass line through the static
bypass commuter switch (figures 17 and 18), provided that the EPO is inactive
3-3-4. Operation in manual bypass, ()
When we wish to perform some maintenance check on the device, it may be disconnected from the mains
without any need to cut the power supply to the system and affect the critical load. The UPS may be
intervened, only by technical or maintenance personnel, by means of the maintenance bypass (following
specific instructions for that purpose).