Endress+Hauser Proline Promass A 100, Руководство по эксплуатации

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Proline Promass A 100 Electrical connection
Hauser 29
To comply with both requirements, the fieldbus system allows three different types of
shielding:
• Shielding at both ends.
• Shielding at one end on the feed side with capacitance termination at the field
device.
• Shielding at one end on the feed side.
Experience shows that the best results with regard to EMC are achieved in most cases
in installations with one-sided shielding on the feed side (without capacitance
termination at the field device). Appropriate measures with regard to input wiring must
be taken to allow unrestricted operation when EMC interference is present. These
measures have been taken into account for this device. Operation in the event of
disturbance variables as per NAMUR NE21 is thus guaranteed.
Where applicable, national installation regulations and guidelines must be observed
during the installation!
Where there are large differences in potential between the individual grounding points,
only one point of the shielding is connected directly with the reference ground. In
systems without potential equalization, therefore, cable shielding of fieldbus systems
should only be grounded on one side, for example at the fieldbus supply unit or at
safety barriers.