SMA SB 3300-11 Installation - Manual (Page 57)

SMA Solar Technology AG Troubleshooting
Installation Manual SB33-38-11-IA-en-62 57
4. Measure the voltages between the positive and
negative poles of each string.
☑ A ground fault exists if the measured voltages are stable and the sum of the voltages from
the positive pole to the ground potential and from the negative pole to the ground potential
of a string is approximately equal to the voltage between the positive and negative poles.
Result Measure
☑ You have found a ground fault. • The installer of the PV array 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 39).
☑ 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 58).