dI-Bfr / dI-Srr — Drastic change in differential current (grounding fault)

What does dI-Bfr / dI-Srr mean?

The inverter has detected a significant change in the differential current. This fault typically occurs in transformerless inverters and is crucial for personal safety, often indicating a sudden grounding fault, residual current, or an internal device fault. The inverter will disconnect from the grid.

• Sudden grounding fault.
• Residual current.
• Actual fault in the device.
• Plant insulation might have a ground fault.

Click steps to track your progress.

1. 1

   Note the specific message displayed (dI-Bfr or dI-Srr) and any other symptoms.

2. 2

   If the message appears for no obvious reason, contact your installer.

3. 3

   Your installer will verify whether the plant insulation might have a ground fault, as described in the inverter installation guide.