Siemens SINAMICS DCM Operating Instructions Manual page 393

Wiring example for a USS bus
1) The shields for the interface cables must be connected directly on the units (using a clamp, for example) to unit or
cabinet ground, with a low level of impedance.
2) Twisted cable, e.g. LIYCY 2×0.5 mm
that the difference in ground potentials between the link partners remains below 7 V.
Figure 10-32 USS bus
SINAMICS DCM DC Converter
Operating Instructions, 1.2012, C98130-A7066-A1-05-7619
; with longer cables, an equipotential bonding cable should be used to ensure
2
Descriptions of functions
10.5 Serial interface with USS protocol
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