Cabinet Configuration - Siemens SIMATIC Ident System Manual

Planning the RF300 system
4.5 Guidelines for electromagnetic compatibility (EMC)
4.5.5

Cabinet configuration

The influence of the user in the configuration of an electromagnetically compatible plant
encompasses cabinet configuration, cable installation, ground connections and correct
shielding of cables.
Note
For information about electromagnetically compatible cabinet configuration, please consult
the installation guidelines for SIMATIC PLCs.
Shielding by enclosure
Magnetic and electrical fields and electromagnetic waves can be kept away from the
interference sink by using a metal enclosure. The easier the induced interference current can
flow, the greater the intrinsic weakening of the interference field. All enclosures and metal
panels in the cabinet should therefore be connected in a manner allowing good
conductance.
Figure 4-13
If the control cabinet panels are insulated from each other, a high-frequency-conducting
connection can be established using ribbon cables and high-frequency terminals or HF
conducting paste. The larger the area of the connection, the greater the high-frequency
conductivity. This is not possible using single-wire connections.
Prevention of interference by optimum configuration
Good interference suppression can be achieved by installing SIMATIC PLCs on conducting
mounting plates (unpainted). When setting up the control cabinet, interference can be
prevented easily by observing certain guidelines. Power components (transformers, drive
units, load power supply units) should be arranged separately from the control components
(relay control unit, SIMATIC S7).
106
Shielding by enclosure
System Manual, 07/2016, C79000-G8976-C345-0x
SIMATIC RF300