SMA SC 500CP-US-10 600V - Manual (Page 41)

SMA America, LLC 3 Product Description
Operating Manual SCCP-US-BE-US_en-52 41
3.8 Islanding Detection
Stand-alone grids form when the following conditions occur simultaneously:
• The medium-voltage grid fails.
• The inverter feeds in an amount x of power. There is an electrical load on the same branch of the grid with a load
equal to that of power x.
There are two methods for islanding detection:
• Active Islanding Detection*
• External Islanding Detection
Active Islanding Detection
The inverter detects the formation of stand-alone grids during a grid failure and disconnects the inverter from the utility
grid.
This function is set via the parameter EnaAID and cannot be active at the same time as the "FRT" function.
External Islanding Detection
In the event of a grid failure, the formation of stand-alone grids is detected at the farm level. If a stand-alone grid is formed,
a signal is transmitted to the fast stop input of the inverter.
If the signal appears at the fast stop input of the inverter while the inverter is in the "MPP load operation" operating state,
the inverter switches to the operating state "Shutdown". Once shutdown is complete, the AC contactor and the DC
switching device open automatically and the inverter switches to the operating state "Stop".
For external islanding detection, a suitable cable must be connected to the inverter fast stop input during installation.
3.9 Schematic Diagram
Schematic diagrams in PDF format contain jump marks. By double clicking a jump mark, the display will change to the
corresponding current path or the referenced place in the equipment list.
SMA recommends using schematic diagrams in PDF format during troubleshooting. The schematic diagrams in PDF
format are available on request. Contact the SMA Service Line.
* Not with SC 850CP-US and SC 900CP-US