RF600 system planning
4.10 Guidelines for electromagnetic compatibility (EMC)
SIMATIC RF600
System Manual, 06/2019, J31069-D0171-U001-A22-7618
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4.10.3
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
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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.
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Use metal connector housings to shield data conductors.
Wide-area ground connection
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Plan a meshed grounding concept.
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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.
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Always route power cables, signal cables and HF cables through separated ducts or in
separate bundles.
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Feed the cabling into the cabinet from one side only and, if possible, on one level only.
●
Route the signal cables as close as possible to chassis surfaces.
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Twist the feed and return conductors of separately installed cables.
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Routing HF cables:
avoid parallel routing of HF cables.
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Do not route cables through the antenna field.
Shielding for the cables
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Shield the data cables and connect the shield at both ends.
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Shield the analog cables and connect the shield at one end, e.g. on the drive unit.
●
Always apply large-area connections between the cable shields and the shielding bus at
the cabinet inlet and make the contact with clamps.
