Beijer Electronics BoX2 pro, Руководство по установке

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Additional Installation Tips
Note:
The grounding wires should be short and the conductor should have a large area.
A long, thin grounding wire has a very high impedance (resistance) at high frequencies
and does not guide disturbances to the ground.
Multi-wire conductors are better than single wire conductors with the same area.
A braided conductor wire with the same area is even better. The best is a short, thick
grounding braid.
6.2 Ethernet Connection in the
Operator Panel
1
2
3
4
5
RJ45
RJ45
RJ45
RJ45
RJ45
RJ45
RJ45
RJ45
Industrial Ethernet
Operator panel
Operator panel
Operator panel
Operator panel
Shielded
Short and
unshielded
0.1 μ F
250 V
1-1
3-3
8-8
2-2
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. Unshielded cabling may even result
in fewer communication errors.
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Beijer Electronics, MAEN275