System issue: DCInj-FAULT
DC injection protection in a solar inverter is designed to detect and respond to the injection of direct current (DC) into the alternating current (AC) side of the system.
This alarm occurs mostly when detected high DC injection current.
- Sudden spikes or overvoltage conditions in the DC side can result in DC injection.
- Ground faults in the DC circuit can lead to the injection of DC into the AC side, triggering the DC injection protection.
- Breakdown or damage to insulation in the DC circuit can cause leakage currents and, subsequently, DC injection.
1. Power-cycle the inverter:
- Disconnect AC and DC connection.
- Restart the inverter after 1 hour and then check.
- If the inverter is not working work normally, then check below mentioned points.
2. PV String Voltage Checks:
- Verify the Open Circuit Voltage (VOC) of each PV string by measuring the voltage from the connector end after disconnecting the string from the inverter. This step ensures an accurate assessment of the individual VOC for each PV string.
- Utilize a multimeter to measure the voltages between PV+ and earth, as well as PV- and earth for all the PV strings. The voltages should exhibit a decreasing trend, falling within the range of 5% to 95% of the Voc (Open Circuit Voltage) of a single PV module. If the voltage remains constant at the Voc of a single module or increases during the decreasing conditions, it indicates a fault within the PV strings that needs to be addressed.
3. Voltage Checks:
- If system is three phase (Check AC side voltage Phase to Phase, phase to neutral and neutral to earthing.) Always check reading from inverter AC gland end.
- If system is single phase (Check AC side voltage Phase to neutral, phase to earthing and neutral to earthing.) Always check reading from inverter AC gland end.
- Take complete reading of information menu like DC1, DC2, DC3, DC4 then VA, VB, VC or VGrid then Status (Error) and Total energy.
4. Replace inverter
If you confirm that the inverter relay is defective, please contact Autarco Support support@autarco.com for a replacement.
This is an inverter-driven issue.
Issue Creation
If the inverter sends a single message with this type of alarm in a 24hr period an issue will be created.
Resolution:
If a 24hr period passes with good production, and not futher alarms, the issue will be automatically resolved.
Still need help? Please raise a case in Helios