Siemens SIMATIC RF300 System Manual page 110

Planning the RF300 system
4.6 Guidelines for electromagnetic compatibility (EMC)
EMC measures usually consist of a complete package of measures, all of which need to be
implemented in order to ensure that the plant is immune to interference.
Note
Adherence to EMC directives
The plant manufacturer is responsible for the observance of the EMC directives; the plant
operator is responsible for radio interference suppression in the overall plant.
All measures taken when setting up the plant prevent expensive retrospective modifications and
interference suppression measures.
The plant operator must comply with the locally applicable laws and regulations. They are not
covered in this document.
4.6.3 Basic rules
It is often sufficient to follow a few elementary rules in order to ensure electromagnetic
compatiblity (EMC).
The following rules must be observed:
Shielding by enclosure
• Protect the device against external interference by installing it in a cabinet or housing. The
housing or enclosure must be connected to the chassis ground.
• Use metal plates to shield against electromagnetic fields generated by inductances.
• Use metal connector housings to shield data conductors.
Wide-area ground connection
• Plan a meshed grounding concept.
• Bond all passive metal parts to chassis ground, ensuring large-area and low-HF-impedance
contact.
• Establish a large-area connection between the passive metal parts and the central grounding
point.
• Don't forget to include the shielding bus in the chassis ground system. That means the actual
shielding busbars must be connected to ground by large-area contact.
• Aluminium parts are not suitable for ground connections.
Plan the cable installation
• Break the cabling down into cable groups and install these separately.
• Always route power cables, signal cables and HF cables through separated ducts or in
separate bundles.
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System Manual, 02/2021, C79000-G8976-C345-09
SIMATIC RF300