EMC_PLC

Cabling

Guidelines for Creating the Ground Connection for Cable Shielding Guidelines for selecting the method of connection NOTE: Always avoid cable shielding without a ground connection. This type of connection is practically useless from an EMC point of view and cannot be permitted for safety reasons if contact protection is not provided.

The table shows how the cable shield should be connected to ground depending on the application: Application

Cable shield ground connection

Shielded analog measuring circuit in the cabinet

 Ground connections are usually found on

one side of the cabinet outlet

 Both ends of the cable shielding ground

for extreme levels of disturbance Shielded analog measuring circuits outside of cabinets in closed buildings

 If only capacitive electrical interference is

to be reckoned with: single cable shielding ground connection  If the signal line is setup with highfrequency influences: double sided cable shielding ground connection  If the signal line is long: in addition to double ground connections along the cable length, further ground connections at intervals from 10 ... 15 m

Long lines For long shielded lines, several ground connections at intervals of 10 ... 15 m along the length of the cable are recommended:

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33002439 10/2019