SMA SSM8-21-BS - Manual (Page 42)

9 Troubleshooting SMA Solar Technology AG
42 SSMxx-21-IA-BS-JP-en-20 Installation Manual
9 Troubleshooting
Symptom Cause and corrective measures
LED DIN1 is off. The surge arrester for the DC main cable has tripped.
Corrective measures:
• If the Sunny String-Monitor is equipped with a modular surge arrester, replace the
defective module in the surge arrester.
• Ensure that the surge arrester for overvoltage protection is functioning.
The LED Error is glowing. The String-Monitor Unit is defective.
Corrective measures:
• Contact the SMA Service Line.
The LED RS485 has been
off for more than five
minutes.
The data cable is damaged or not properly connected and terminated.
Corrective measures:
• Ensure that the data cable is connected correctly (see Section 6.7 "Connecting the
Data Cables", page 31).
• Ensure that the cabling between the Sunny Central and the Sunny String-Monitors is
OK.
• Ensure that the data cable in the last Sunny String-Monitor of a string is terminated (see
Section 7.2.2 "Terminating the Data Cable", page 38).
The serial interface is not correctly configured.
Corrective measures:
• Configure the serial interface correctly (see user manual of the inverter).