SMA America, LLC Displays and messages
Installation Guide SB30-40US-IUS103030 67
Control system fault
The yellow LED remains lit.
The Sunny Boy has detected a fault within the internal monitoring systems. When the inverter detects
a fault of this kind it will no longer connect to the utility grid. To correct this, the inverter must be
serviced by a qualified service technician. Contact SMA for assistance.
Grid failure
The yellow LED is on for 5 seconds, out for 3 seconds and then blinks twice. The code is repeated
3times. This code sequence will repeat as long as there is a grid fault condition.
This code can be caused by any of the following conditions:
• Low Grid Voltage (<Vac Min)
• High Grid Voltage (>Vac Max)
• Low Grid Frequency (< fac Min)
• High Grid Frequency (>fac Max)
• Rapid change in grid frequency or voltage
Check the condition of the grid at the AC terminal blocks within the Sunny Boy. Also inspect the AC
disconnect between the Sunny Boy and the grid.
DANGER
Risk of electric shock due to high voltages inside the inverter.
• Do not touch power cables and screw termnals.
• The checking must be done by qualified personnel only.