Event 7703

Qualified person

Event message:

  • Self-diagnosis / SlfDiag

  • Interference device / DevFlt

Explanation:

Error during the relay test. An internal relay can no longer be opened or closed. This means that the inverter cannot connect to the utility grid. The cause may be a faulty relay. The relay contacts can be damaged by transient overvoltages in the AC grid or a ground fault in the DC installation. The event message may also occur temporarily in the event of fluctuations in the utility grid.

Corrective measures:

  • Ensure that the AC connection at the inverter and at the point of interconnection is correctly executed. Repair or replace defective terminal points and fuses.

  • Ensure that screw-type fuses are not used as load-break switches.

  • Check the system's AC grid. Do this by measuring the voltage between N and the individual line conductors. The voltage should be the same as the mains voltage and almost identical for all conductors. Also measure the voltage between N and PE. This should be less than 10 V.

    Greater voltage differences may indicate a displaced neutral point due to faulty or insufficient grounding measures.

  • If the event message persists after the corrective measures, the assembly or inverter needs to be replaced.

    Event 7702
    Event 7801