9 troubleshooting, 1 the red led is continuously on, 1 checking the pv generator for ground fault – SMA SB 1100 User Manual
Page 36: Troubleshooting, The red led is continuously on, Checking the pv generator for ground fault
Troubleshooting
SMA Solar Technology AG
36
SB11_12_17-IEN100132
Installation Guide
9 Troubleshooting
If the Sunny Boy displays other blink codes or display messages than those described in
section 6 "Commissioning the Sunny Boy" (page 26), refer to the associated user manual in order to
obtain the precise meaning of the display messages or the blink codes and, if necessary, the error
correction.
Do not undertake any repairs that are not described here, but rather use the 24-hour replacement
service (the Sunny Boy will be sent within 24 hours) and the repair service of SMA Solar Technology.
9.1 The red LED is continuously on
If the red LED of the status display is continuously on during operation, there is either a ground fault
in the PV generator or at least one of the varistors for the overvoltage protection is defective.
9.1.1 Checking the PV Generator for Ground Fault
1. Disconnect the Sunny Boy from both the DC and AC connections, as described in
section 7.1 "Opening the Sunny Boy" (page 32).
2. Measure the voltages between the plus and minus
pole of a string against the ground potential.
☑ If voltage is found, there is a ground fault in the
corresponding string.
NOTICE!
Excessive voltages can destroy the measuring device!
• Only use measuring devices with a DC input voltage range up to at least 500 V.
DANGER!
Risk of lethal electric shock!
In case of a ground fault, the PV generator may carry high voltages.
• Do not touch the frame of the PV generator.
• Wait until no voltage can be measured.
• Do not connect strings with ground faults to the Sunny Boy.