Start Up And Connection To The Grid - Power One AURORA Manual Del Usuario

9. Start up and connection to the grid

Once the pre-commissioning checks have been performed, it is possible to proceed to starting up the inverter and connecting
it to the grid, following the procedure shown below.
Put the built-in disconnecting switch (versions –S and –FS) to the ON position or close the external disconnecting
switches: if the input voltage applied to one of the two input channels is greater than the minimum default voltage, the
inverter will light up showing the "Initializing...please wait" message on the display.
Depending on the input voltage value, the inverter will show various messages on the display and change the behaviour
of the three LED:
Input voltage
Vin<Vstart
Vin>Vstart
Note: the inverter is powered ONLY by the voltage coming from the photovoltaic generator: presence of grid voltage alone IS NOT
SUFFICIENT to permit the inverter to start up.
Note: the inverter start-up voltage (Vstart) is the input voltage value though which the inverter connects to the grid. This
value avoids repeated connection and disconnection in periods of reduced radiation (typically in the morning). It is possible
to modify the start-up voltage within a set range via the display and the four keys (Ref. Par. 10 and the technical data table in
Appendix C).
Nevertheless, it is advisable to reduce the start-up voltage only when really necessary or when modifi cation of the parameter
is required by the confi gurer; this is to avoid repeated connection and disconnection to the grid which could lead to stress on
the parallel grid electromagnetic devices (relays). For more information in this respect refer to the user manual on the CD that
comes in the package.
Note: the start-up voltage also sets the minimum voltage for the inverter to operate in MPPT. The inverter turns itself off because of
input undervoltage when the input voltage (for each channel) drops below 70% of the start-up voltage (for the channel). For more
information in this respect refer to the user manual on the CD that comes in the package.
With the inverter in "No Vac" status, close the AC switch downstream the inverter so as to apply the grid voltage to the inverter: the inverter
performs the grid voltage check, measures the photovoltaic fi eld' s insulation resistance against earth and carries out other self-diagnosis
checks. During the checks before the parallel with the grid, the green LED keeps fl ashing, the others are off.
Note: during the grid voltage check and measurement of the insulation resistance, the values for the grid voltage and frequency and
the insulation resistance measured by the inverter are shown on the display. The inverter completes parallel with the grid SOLELY if the
grid parameters meet the ranges provided for by the regulations in force and if the insulation resistance is greater than 1Mohm.
If the preliminary checks for parallel to the grid are successful, the inverter connects to the grid and begins to export power to the
grid. At this stage, the display shows the inverter' s parameters in cycles. The green LED stays lit whereas the others are off.
Turning off the unit: follow the operations described for commissioning in reverse order. Opening the switch downstream the
inverter will light up the yellow LED and display message W003 and then "No Vac"; opening the built-in disconnection switch or
the external disconnection switches will completely turn off the unit (LED off and display off).
Note: during the night, or more generally when the input voltage (DC) is insuffi cient to turn on the internal auxiliary power supply,
the inverter will be completely off.
Photovoltaic Inverters
Display message
Green=FLASHING
Waiting sun Yellow=OFF
Red=OFF
Green=FLASHING
No Vac Yellow=ON
Red=OFF
LED status
The input voltage is not suffi cient to permit
connection to the grid.
There is suffi cient input voltage to permit
connection to the grid: the inverter waits until there
is grid voltage to carry out the parallel.
17 - EN
Description