Troubleshooting
SMA America, LLC
210
SI5048U-TUS121440
Technical Description
Why does the ”VAC-Low” error (output voltage too low) also occur when the
Sunny Island is started?
• A permanent short-circuit exists in the off-grid power system. Check the AC output connections
of the off-grid power system (see section 6.3 ”AC Connection” (page 46)).
• The loads connected to the off-grid power system are too heavy. The power/electrical energy
of the Sunny Island is not sufficient to supply the loads. Switch off some of the loads and restart
the Sunny Island.
Why is the off-grid frequency not at 60 Hz?
• The Sunny Boy inverter is controlled via the frequency (see section 17.5 ”Frequency Shift Power
Control (FSPC)” (page 147)).
• The ”AFC” function of the Sunny Island 5048U is activated (see section 12.6 ”Automatic
Frequency Control (AFC)” (page 104)).
• Power fluctuations cause frequency deviations.
What do I do when a battery cell can no longer be used?
• Remove the unusable cell from your battery bank. Start the Sunny Island and change the battery
voltage in the QCG under ”New Battery”.
What can I do when the QCG does not run?
• Switch off the Sunny Island (see section
9.3 ”Switching off” (page 74)
) and restart it (see
section 9.1 ”Switching on” (page 72)).
What happens when ”MMC operation failed” is displayed?
• You wanted to perform an action using the SD card, but it failed (see section 10.9 ”Display of
Warnings and Failures” (page 91)). Check the card (on your PC/laptop) and use a new SD
card, if necessary.
Why does my Sunny Island stay on even though I switched the DC circuit breaker
to Off?
• Your Sunny Island may be powered by the AC side. Switch off all AC loads and disconnect
them from the Sunny Island (see section 9.4 ”Disconnecting the Device from Voltage Sources”
(page 74)).
Why is my battery discharging even though the generator is running?
• The power produced by the generator does not reach the Sunny Island. Check the voltage and
frequency values. The fuses on the generator may have been triggered.
• The consumer power exceeds the generator power ”234.03 GnCurNom”.
– Check error messages Find the cause.
Why is the deactivation defined by the SOC in case of a full or equalization
charge and generator start in the second time zone?
• Equalization charge has a higher priority than silent time.
