Mitsubishi Electric E1151, Руководство по установке

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Additional Installation Tips
20 Mitsubishi Electric, MA00780C
6.2 Ethernet Connection in the Panel
1. In some industrial units for Ethernet, the RJ45 contact’s shield is connected to
the chassis via a capacitor.
2. The operator panel’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.
A good solution may be to use a shielded Ethernet cable , but to connect the shield at
one end only.
3. One option is to break the shield.
4. A more elegant method is to expand the shielded Ethernet cabling with a piece
of unshielded Ethernet cable.
5. You can ground the shield via an external 0.1 uF/250 V plastic capacitor. This
will connect the HF transients to the ground.
1
2
3
4
5
5351
1-1
2-2
3-3
8-8
Industrial Ethernet
RJ45
RJ45
RJ45
RJ45
RJ45
RJ45
RJ45
RJ45
Operator panel
Operator panel
Operator panel
Operator panel
Shielded
Short and
unshielded
0.1 uF
250 V