Siemens SINAMICS S120 Manual page 124

Line Modules
3.3 Smart Line Modules
High leakage current
Smart Line Modules discharge a high leakage current to the protective ground conductor.
Due to the high leakage current associated with Smart Line Modules, they or the relevant
control cabinet must be permanently connected to PE.
According to EN 61800-5-1, Section 6.3.6.7, the minimum cross-section of the protective
ground conductor must conform to the local safety regulations for protective ground
conductors for equipment with a high leakage current.
122
DANGER
Manual, (GH3), 01/2013, 6SL3097-4AE00-0BP3
Chassis power units