Danfoss FC 300 Profibus Manual page 15

FC 300 Profibus
Earth Connection
It is important that all stations connected to the PROFIBUS network are connected to the same earth
potential. The earth connection must have a low HF (high frequency) impedance. This can be achieved by
connecting a large surface area of the cabinet to earth, for example by mounting the FC 300 series on a
conductive rear plate. Particularly when there are long distances between the stations in a PROFIBUS
network, it can be necessary to use additional potential equalizing cables, connecting the individual stations
to the same earth potential.
Cable Routing
The PROFIBUS communication cable must be kept away from motor and brake resistor cables to avoid
coupling of high frequency noise from one cable to the other. Normally a distance of 200 mm is sufficient,
but maintaining the greatest possible distance between cables is generally recommended, especially where
cables run in parallel over long distances.
If the PROFIBUS cable must cross a motor cable or brake resistor cable, the cables must cross at an angle
of 90°.
How to Install
MG.33.C2.02 - VLT is a registered Danfoss trademark
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