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Safety -2, Safety – SMA SB 3800-U User Manual

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SMA America

SB3800U-12:SE2006

Note:

Policies vary from one utility company to another. Consult

with a representative of the local utility company before

designing and installing a PV system.

Safety

Anti-Islanding Protection

Islanding is a condition that can occur if the utility grid is disconnected while the
SB3800U is operating and the remaining load is resonant at 60 Hz and matches the
output of the SB3800U perfectly. This condition is highly unlikely and had never been
witnessed outside of a controlled laboratory. Nevertheless, the SB3800U 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
SB3800U 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 SB3800U is equipped with a ground fault detection device. If a ground fault current
greater than 1 Amp is detected, the SB3800U 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 SB3800U has been tested and certified by ETL 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 519 Standard Practices and Requirements for Harmonic Control in Electrical
Power Systems.

The SB3800U is also ETL listed under UL1741 for use in Canada.