Connections And Interference Suppression - Siemens SINAMICS G120D Getting Started

● Route all power cables (line supply cables, as well as motor cables) separately from
signal and data cables. The minimum distance should be approximately 25 cm.
Exception: hybrid motor cables with integrated shielded temperature sensor and brake
control wires are allowed.
● Shield the power cable between inverter and motor. We recommend shielded cables with
symmetrical three-phase conductors (L1, L2, and L3) and an integrated, 3-wire, and
symmetrically arranged PE conductor.
Cable shields
● Use shielded cables with finely stranded braided shields. Foil shields are not suitable
since they are much less effective.
● Connect shields to the grounded housings at both ends with excellent electrical
conductivity and a large contact area.
● Bond the cable shields to the plug connectors of the inverter.
● Don't interrupt cable shields by intermediate terminals.
● In the case of both, the power cables and the signal and data cables, the cable shields
should be connected by means of suitable EMC shield clips or via electrically conductive
PG glands. These must connect the shields to the shield bonding options for cables and
the unit housing respectively with excellent electrical conductivity and a large contact
area.
● Use only metallic or metallized connector housings for shielded data cables (e. g.
PROFIBUS cables).
3.7

Connections and interference suppression

All connections should be made so that they are permanent. Screwed connections on
painted or anodized metal components must be made either by means of special contact
washers, which penetrate the isolating surface and establish a metallically conductive
contact, or by removing the isolating surface on the contact points.
Contactor coils, relays, solenoid valves, and motor holding brakes must have interference
suppressors to reduce high-frequency radiation when the contacts are opened (RC elements
or varistors for AC currentoperated coils, and freewheeling diodes for DC current-operated
coils). The interference suppressors must be connected directly on each coil.
SINAMICS G120D converter
Getting Started, 07/2016, FW V4.7 SP6, A5E38556189B AA
3.7 Connections and interference suppression
Installation
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