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Connecting
6.5 Grounding of the Ethernet cable
SENTRON PAC4200
Manual, 09/2008, A5E02316180B-01
83
Design
Ground the Ethernet cable at both ends. To do this, expose the foil shield of the Ethernet
cable. Connect the exposed shield to a suitable grounding point on the control cabinet,
preferably a shielding bus.
Figure 6-22 Grounding of the Ethernet cable
● Be careful not to damage the foil shield of the cable when removing the cable jacket.
● Fasten the exposed shield with a metal cable clamp or alternatively with a hose tie. The
clamp must clasp around a large portion of the shield and provide good contact.
● To allow good contact, a tin-plated or galvanically stabilized surface is ideal. With
galvanized surfaces, the contact should be achieved using suitable screws. A painted
surface at the contact point is not suitable.
CAUTION
Loss of contact if the shield connection is incorrectly used for strain relief
If the shield connection is used for strain relief, the grounding contact can deteriorate or
be completely lost.
Don't use the contact point on the cable shield for strain relief.
CAUTION
Illegally high compensating current if there is a potential difference between grounding
points
If there is a potential difference between grounding points, an illegally high
compensating current can flow through the shield grounded at both ends.
Never interrupt the shield of the Ethernet cable! Install an additional bonding conductor
that takes over the shield current.