SMA SB 1100 - Manual (Page 37)

SMA Solar Technology AG Troubleshooting
Installation Guide SB11_12_17-IEN100132 37
The approximate position of the ground fault can be determined from the ratio of the measured
voltages between plus against ground potential and minus against ground potential.
Example:
The ground fault is between the second and third module in this case.
3. Repeat step 2 for each string.
The table illustrated below shows the various results and corresponding measures.
☑ The ground fault check is finished.
Result Action
☑ You have found a ground fault. • The installer of the PV generator must
remedy the ground fault in the affected
string before you may reconnect the string
to the Sunny Boy.
• Do not reconnect the faulty string.
• Close and commission the Sunny Boy as
described in section 7.2 "Closing the
Sunny Boy" (page 33).
☑ You have found no ground fault. It is likely that one of the thermally monitored
varistors is defective.
• Check the varistors as described in section
9.1.2 "Checking the Function of the
Varistors" (page 38).