Siemens SINAMICS S210 Operating Instructions Manual page 43

Neutral conductor fire caused by high currents
If you connect the converter without an isolation transformer to a supply system with 400 V
3 AC between the N-conductor and a line conductor (L1, L2 or L3), the harmonic currents in
the N-conductor can add up to values that are greater than the currents in the line conductors.
This heats up the N-conductor and can cause a fire.
● Take the harmonic currents into account when dimensioning the power supply cables.
SINAMICS S210 servo drive system
Operating Instructions, 12/2017, A5E41702836B AA
WARNING
3.2 Permissible line supplies and connection options
Configuring
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