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Fieldbarrier – VEGA FIELDBARRIER User Manual

Page 20

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FieldBarrier

Subject to reasonable modifications due to technical advances.

Copyright Pepperl+Fuchs, Printed in Germany

Pepperl+Fuchs Group • Tel.: Germany +49-621-776-0 • USA +1-330-4253555 • Singapore +65-67-799091 • Internet www.pepperl-fuchs.com

08/

2007 122329

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If the shield is only applied on one side, EMC protection is less reliable. In this case
as well, there is no need for the potential equalization conductor in the case of non Ex
applications.

Pepperl+Fuchs always recommends the use of shielded lines for the
fieldbus. The shield should be hard grounded on the segment coupler/
Power Repeater, FieldBarrier and on all field devices. Please note in
this regard chapter 4.6.
For intrinsically safe applications, a potential equalisation between the
hazardous and the safe area is required. Note in this regard the respec-
tive relevant setup requirements.
If there is no potential equalisation between the hazardous and the safe
area, there is a possibility of capacitive grounding on the segment cou-
pler/Power Repeater or FieldBarrier.
The capacitor used must have a fixed dielectric. For the capacitance of
the capacitor, the following applies: C < 10 nF. In addition, the capacitor
must be designed for a test voltage of > 1500 V.