6 Earthing and shielding
| Shielding of cables
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2484950000/00/03.2016
Manual UR67-PROIFBUS
Sensor and actuator lines
To avoid antenna effects caused by looped lines, all lines that
go to a certain sensor or actuator should be combined in one
cable.
Cabinet design according to EMC guideline:
2
4
5
6
7
3
1
1 Earthing strips
Earthing strips must be used for connecting inactive metal
parts if it is not possible to connect two large pieces of met-
al. Use short earthing strips with large surfaces.
2 Clamping bracket for signal cables
If shielded signal cables are used, the shield must be at-
tached to the clamping bracket (KLBÜ series) on the busbar
over a large surface. The braided shield must cover and make
good contact with a large part of the clamping bracket.
3 Mounting plate
The support beam for holding control components must be
connected to a large part of the cabinet housing.
4 Busbar
The busbar must be connected via the rail holding fixture.
The cable shields are fixed to the busbar.
5 Protective earth conductor rail
The protective earth conductor rail must likewise be attached
to a large part of the mounting plate, and it must be con-
nected to the protective earth conductor system via an exter-
nal cable with a cross-section of at least 10 mm
2
, in order to
discharge interference current.
6 Protective earth terminal strip
The protective earth terminal strip must be connected to the
protective earth conductor rail in a neutral-point configura
-
tion.
7 Cable to protective conductor system (earthing
point)
The cable must be connected to a large part of the protective
conductor system.
See also:
EMC Directive 2014/30/EU
6.4 Shielding of cables
To prevent the coupling of interference voltages and the de-
coupling of interference fields in cables, only shielded cables
made from well-conducting material (copper or aluminium)
with braided shielding and a coverage of at least 80 %
should be used in the design of a cable shield.
