SMA SB 700U - Manual (Page 11)

SB700U-11:SE3207 SMA America 1-3
Safety
Anti-Islanding Protection
Islanding is a condition that can occur if the utility grid is disconnected while the
Sunny Boy is operating and the remaining load is resonant at 60 Hz and matches
the output of the Sunny Boy perfectly. This condition is highly unlikely and had never
been witnessed outside of a controlled laboratory. Nevertheless, the Sunny Boy
incorporates an advanced active islanding protection algorithm to insure that the
system will not export power into a balanced 60 Hz resonant load while the utility
is disconnected. The Sunny Boy periodically injects both leading and lagging
reactive current into the utility grid. This method has been proven by U.S. regulatory
agencies to effectively destabilize and disconnect from a balanced island condition.
PV Ground Fault Detection and Interruption
The Sunny Boy is equipped with a ground fault detection device. If a ground fault
current greater than 1 Amp is detected, the Sunny Boy will shut down and display
the fault condition on the user interface display. Once the ground fault is located
and corrected, the ground fault error will need to be manually cleared and the
inverter will then resume normal operation.
PV Series Fusing
Series fusing may be required depending on the type of PV module used in the
system. See NEC 690.9
Interconnection Code Compliance
The Sunny Boy has been tested and certified by UL to meet the requirements of
UL1741 Static Inverters and Charge Controllers for use in Photovoltaic Power
Systems as well as IEEE-929-2000 Recommended Practice for Utility Interface of
Photovoltaic Systems and IEEE 1547 Standard for Interconnecting Distributed
Resources with Electric Power Systems. The Sunny Boy is also UL listed under
UL1741 for use in Canada.