Grid Reconnection; Grid Operation - SMA Sunny Island 5048 Installation Instructions Manual

SMA
Technologie AG Connecting External Sources
As long as the battery has a sufficient charge level, the loads are powered. In stand-
alone operation, the AC feed-in generators (e.g. Sunny Boys) perform a charge
operation, if required.

14.2.4 Grid Reconnection

In stand-alone operation, the inverter constantly checks whether the gird has been
reconnected (see above). If the voltage and frequency of the main power grid are
within the permissible range of the "#250.01 GdVtgMin" and "#250.02 GdVtgMax"
parameters for the "#250.07 GdVldTm" time and the frequency is within the permissible
range of the "#250.05 GdFrqMin" and "#250.06 GdFrqMax" parameters (see also
section 14.2.1 "Conditions" (Page 110)), the stand-alone grid is synchronized with the
main power grid and then connected.

14.2.5 Grid Operation

In grid operation, the stand-alone grid and main power grid are connected. The inverter
is simultaneously connected along with the stand-alone grid to the main power grid. In
this case, the voltage and frequency in both grids are identical.
All grid failures that occur during grid operation affect the stand-alone grid.
In grid operation, the grid monitors whether the permissible limits for voltage and
frequency (see Grid Reconnection) are maintained or whether the grid fails to assume
powering the stand-alone grid. To do this, the main power grid is disconnected (grid
backup operation).
The battery is generally charged or its charge is maintained on the grid.
Charge Mode
Charge mode on the grid is indicated by energy flowing to the battery. The battery is
charged until the respective charge process (Boost, Full, Equalize) has been completed
and the system transitions into float charge (Float).
Silent Mode
In order to save energy, the silent mode can be activated using the "#224.01
SilentEna" parameter along with the enable setting (Default Disable). In this case, the
Sunny Island 5048 is set into the sleep mode if the charge has been completed and the
battery was in float charge for some time (see section 13.4.5 "Silent Mode" (Page 91)).
The silent mode is exited regularly to recharge the battery.
Grid Feeding
Whether energy is fed from the stand-alone grid into the main power grid is controlled
using the "#250.08 GdMod" parameter. If GridCharge (Default) is set, no energy is
fed into the grid. If GridFeed is set, energy is fed into the grid.
Technical Description SI5048-11:EE4206 Page 111