Checking the Function of the Surge Arresters
Qualified person
Surge arresters are wearing parts. Their functionality diminishes with age or following repeated exposure to overvoltage. It is therefore possible for the surge arresters to lose their protective function over time.
Check the function of the surge arresters as described in the following.
Procedure:
- Disconnect the inverter from all voltage sources ( > Disconnecting the Inverter from Voltage Sources).
- Wait 20 minutes before removing the DC protective cover.
- Release the screws on the DC protective cover using an Allen key (AF 3), lift the DC protective cover upwards from below and remove it.
- Check whether one of the surge arresters is defective.
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Order new surge arresters.
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If new surge arresters are available, replace all surge arresters ( > Replacing the Surge Arrester).
- Tighten all four screws on the DC protective cover with an Allen key (AF 3) in the sequence 1 to 4 (torque: 3 Nm ± 0.3 Nm).
- Recommission the inverter ( > Recommissioning the Inverter).
DANGER
Danger to life due to electric shock


If no stripe is visible next to the type designation in the inspection window of the surge arrester, the surge arrester is in good condition.
If a red stripe is visible next to the type designation in the inspection window of the surge arrester, the surge arrester is defective.
