Inductive Coupling - Siemens SINAMICS G130 Engineering Manual

SINAMICS G130 converter chassis units and SINAMICS S120 chassis units as well as SINAMICS G150 and S150
converter cabinet units, and S120 Cabinet Modules offer a range of shield bonding options:
•
Each SINAMICS device is supplied with shield clips to ensure an optimum shield connection of the signal
cables.
•
In addition the shields of the signal cables can also be bonded to comb-shaped shield bonding points by
means of cable ties.
Shield bonding options for SINAMICS chassis units and cabinet units
From the EMC point of view, the use of intermediate terminals should be avoided wherever possible because
interruptions in the shield reduce its effectiveness. If it is impossible to avoid the use of intermediate terminals in
certain cases, however, the signal cable shields must be properly bonded immediately before and after the
intermediate terminals on clamping rails. The clamping rails must be connected to the cabinet housing at both ends
with excellent electrical conductivity and with a large contact area.
Clamping rail
Housing
Shield connection of signal cables in the converter cabinet by means of clamping rails when using intermediate terminals

Inductive coupling

Inductive coupling occurs between different current-carrying circuits or between different conductor loops. If an AC
current is flowing in one conductor loop, this generates a magnetic alternating field, which penetrates the other
conductor loop and induces a voltage in this loop. The magnitude of the inductive coupling can be described in terms
of the counterinductance M
the conductor loops.
Shield
clips
, which depends on the geometry of the conductor loops and on the distance between
K
EMC Installation Guideline
Engineering Information
Cable
ties
Cable tie
Intermediate terminals
SINAMICS Engineering Manual - May 2008
© Siemens AG
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