Ground Fault Detector Interrupter (Gfdi) - SMA Sunny Boy SWR 1800U Technical Description

Sunny Boy 1800U Technical Description

2.3.6 Ground Fault Detector Interrupter (GFDI)

The GFDI is supposed to interrupt the connection to ground of the PV panel in case a
ground leakage current of 1 A is exceeded. This ground fault current is the result of a
ground fault of the PV panel. The inverter then has to indicate this condition and dis-
connect from the grid. The inverter has to be reset manually, it cannot restart auto-
matically.
In grid-feeding mode the ground current is continuously monitored by two independ-
ent systems, the sequential control system and the current control system. If the
maximum current intensity is exceeded the inverter switches to "permanent disable"-
"Earth-currentmax". This is indicated by the red and yellow LEDs.
In addition the voltage between the ground and PV-minus is monitored. If the voltage
exceeds the maximum value defined the failure "GFDI Fuse Open" is displayed and
the inverter stops feeding to the grid. This failure is indicated by the red LED. The
"GFDI Fuse Open" failure persists in case the GFDI fuse is defective.
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SB1800U-11:EE
SMA Regelsysteme GmbH