Graphic Operator Terminal /
INSTALLATION TIPS
Note
: The grounding wires should be short and the conductor should have a large area. A
long, thin grounding wire has very high impedance (resistance) at high frequencies and will
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 better. The
best is a short, thick grounding braid.
6.2 Ethernet
Connection in the Terminal
In some industrial units for Ethernet, the RJ45 contact’s shield is connected to the chassis via
a capacitor.
The graphic operator terminal’s Ethernet shield is directly connected to the chassis.
Check whether the other Ethernet unit has its shield directly grounded or grounded via a
capacitor.
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.
As a solution, use a shielded Ethernet cable. However, only connect the shield at one end.
A possible option is to break the shield.
Another option is to expand the shielded Ethernet cabling with a piece of unshielded Ethernet
cable.
You can ground the shield via an external 0.1 uF/250 V plastic capacitor. This will connect
the HF transients to the ground.
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