Connection To The Grid (Ac Supply) - Aros APPENDIX 1500 Manual De Instrucciones

5.4

Connection to the grid (AC supply)

1. The inverter contained in this box has been designed to operate connected to
low voltage grid. This grid must be TT, TN or TN-S. If the present inverter is
connected to a different kind of grid, as an example IT, it is possible to get the
following errors: "Isolation fault" or "Consistent fault"
2. Every country has a regulation about the maximum allowed phase unbalance
and the maximum allowed transformerless power. In case it is necessary to
connect this inverter to grid trough a low frequency transformer, it is necessary
to create locally the correct kind of grid: TT or TN. In order to do this, it is
necessary to connect the local neutral of the transformer to protection earth.
Some examples are available in appendix, in "Table 2". The numbers in the
table have the following meaning:
1.
2.
3.
In case of monophase transformers, the winding side connected to ground
becomes the neutral.
3. In case of PV plants connected to the grid trough a medium to low voltage
transformer, it is necessary to connect the center of the low voltage side star to
ground.
The ground reference is missing: IT system
There is no galvanic insulation between inverters and grid:
measurement errors are introduced.
The star center on grid side is not connected. The star voltage on
the inverter side heavily varies depending on the amount of power
fed to each line.
- ENGLISH -
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