Emc Guidelines; Avoiding Electromagnetic Interference; Connections And Interference Suppression; Cabling - Siemens SINAMICS G120P Hardware Installation Manual

Connecting

4.9 EMC guidelines

4.9 EMC guidelines
4.9.1

Avoiding electromagnetic interference

Only the concurrent use of filtering, grounding and shielding ensure an installation in
accordance with the EMC requirements.
The next sections cover all of the most important rules for the installation of inverter and
drive systems.
4.9.2

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.
4.9.3

Cabling

Cables
● All cable lengths must be minimized (excessive cable lengths must be avoided).
● Signal and data cables, as well as their associated equipotential bonding cables, must
● Spare wires for signal and data cables must be grounded at both ends to create an
● All power cables (line supply cables, as well as motor cables) must be routed seperately
● The power cable between inverter and motor must be shielded. A symmetrical, 3-wire,
● The shielded power cable to the motor must be routed separately from the cables to the
● Signal and data cables must be shielded to minimize coupled-in interference with respect
● Particularly sensitive signal cables, such as setpoint and actual value cables must be
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always be routed in parallel and with as short a distance as possible.
additional shielding effect.
from signal and data cables. The minimum distance should be approximately 25 cm.
three-phase cable should be used here. Shielded cables with symmetrical three-phase
conductors (L1, L2, and L3) and an integrated, 3-wire, and symmetrically arranged PE
conductor are ideal for this purpose.
motor temperature sensors (PTC/KTY), since the latter two are treated as signal cables.
to capacitive, inductive, and radiative coupling.
routed with optimum shield bonding at both ends and without any interruptions of the
shield.
Hardware Installation Manual, 2010-07-02, A5E02923635A AB
Power Module PM230 IP55