Beijer Electronics EXTER T100 bl - Ethernet Connection in the Panel

Additional Installation Tips
6.2 Ethernet Connection in the Panel
1
2
3
4
5
1-1
2-2
3-3
8-8
RJ45
RJ45
RJ45
RJ45
RJ45
RJ45
RJ45
RJ45
Industrial Ethernet
Operator panel
Operator panel
Operator panel
Operator panel
Shielded
Short and
unshielded
0.1 uF
250 V
5351
In some industrial units for Ethernet, the RJ45 contact’s shield is connected to the
chassis via a capacitor, see 1 in drawing above.
The operator panel’s Ethernet shield is directly
connected to the chassis, see 2 in
drawing above.
1.
Check whether the other Ethernet unit has its shield directly grounded or
grounded via a capacitor.
Note:
In many cases, connecting the shielded Ethernet cabling to the chassis at both ends is
inappropriate. Hum or grounding loops can occur. Unshield ed cabling may even result
in fewer communication errors.
A good solution may be to use a shielded Ethernet cable, but to connect the shield
at one end only.
One option is to break the shield, see 3 in drawing above.
A more elegant method is to expand the shielded Ethernet cabling with a piece of
unshielded Ethernet cable, see 4 in drawing above.
You can ground the shield via an external 0.1 µF/250 V plastic capacitor, see 5 in
drawing above. This will connect the HF transients to the ground.
Beijer Electronics, MAEN852B
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