Siemens SINAMICS S120 Equipment Manual page 315

All cables inside the cabinet must be connected as closely as possible to parts connected
with cabinet ground, such as a mounting plate or cabinet wall. Ducts made of sheet steel or
routing cables between between steel sheets (e.g. between the mounting plate and back
wall) should provide adequate shielding.
Avoid, where possible, routing unshielded cables, connected to the drive line-up, in the
immediate vicinity of noise sources, e.g. transformers. Signal lines (shielded and unshielded)
connected to the drive line-up, must be routed as far as possible away from strong external
magnetic fields (e.g. transformers, line reactors). In both cases, a distance of ≥ 300 mm is
usually sufficient.
Caution
The Voltage Clamping Module conducts a high leakage current via the functional ground.
This means that a permanent PE connection must be provided for the cabinet (PE) rail.
Measures according to EN 61800-5-1 must be taken (e.g. PE conductor (≥10mm
an additional connection terminal for a PE conductor with the same cross-section as the
original PE conductor).
Signal and DC power supply cables
Operating unshielded signal and direct current supply cables (e.g. 24 V infeed with external
supply):
• Direct current supply cables: Max. permissible length: 10 m
• Unshielded signal cables: Max. permissible length: 30 m (without additional wiring)
For greater lengths, suitable wiring must be connected by the user to provide overvoltage
protection. For example:
Table 8-9
DC supply
Weidmüller
Type no.: PU DS 24V 16A
Weidmüller GmbH & Co. KG
An der Talle 89
D-33102 Paderborn
Tel. +49 (0)5252/960-0
Fax +49 (0)05252/960-116
http://www.weidmueller.com
Equipment Manual for Booksize Power Units
Equipment Manual, (GH2), 03/2006 Edition, 6SL3097-2AC00-0BP3
8.5 Information about electromagnetic compatibility (EMC) and cable routing
Recommendations for overvoltage protection
Cabinet Configuration and EMC Booksize
24 V signal cables
Weidmüller
Type no.: MCZ OVP TAZ
Cu) or fit
2
8-19