Siemens SINAMICS G120C Operating Instructions Manual page 39

Measures for high frequency equipotential bonding
Proceed as follows, to ensure high-frequency equipotential bonding:
● Connect the metallic components in the control cabinet to the PE bar and the EMC bar
through a larger surface area so that a good electrical connection is established.
– Either through a large surface area between the metal contact surfaces of the cabinet
– Or, alternatively using short, finely stranded, braided copper wires with cross-sections
● In plants and systems with several cabinet elements, screw the frames of the individual
cabinet elements at several locations to one another using serrated washers to establish
a good electrical connection.
● In plants and systems with very long rows of cabinets, which are installed in two groups
back to back, connect the PE bars of the two cabinet groups at as many locations as
possible.
● Therefore, connect the protective ground conductor and the cable shield to the motor and
the inverter.
Additional measures for high frequency equipotential bonding
Route finely stranded or braided copper conductors in parallel to the motor cable with the
shortest possible distance between them:
● in older systems with already existing unshielded cables
● for cables with poor high-frequency properties of the shield
● for poor grounding systems
SINAMICS G120C converter
Operating Instructions, 07/2015, FW V4.7 SP3, A5E34263257B AC
components with a minimum cross-section of several cm² for each contact location.
≥ 95 mm² / 000 (3/0) (-2) AWG.
Installing
4.2 EMC-compliant installation
35