SMA SUNNY BOY 3800 - Page 59

SMA Solar Technology AG Troubleshooting
Installation Guide SB33_38-IEN111851 59
4. Measure the voltages between the plus pole and
the minus pole of each string.
☑ If the voltages measured are stable and the total of the voltages from the plus pole against
ground potential and the minus pole against ground potential of a string roughly
corresponds to the voltage between the plus pole and minus pole, then there is a ground
fault.
Result Measure
☑You have found a ground fault. • The installer of the PV generator must
remedy the ground fault in the affected
string. You can determine the location of the
ground fault as described below.
•Do not reconnect the faulty string.
• Commission the inverter as described in
section 6.1”Commissioning the Inverter”
(page37).
☑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
9.3.2”Checking the Function of the
Varistors” (page60).