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Cable ducts used for information technology
or power supply cabling systems
Separation Separation without
classification electromagnetic Open metallic Perforated metallic Solid metallic
a)
d)
b) c)
(from Table 3) barriers cable duct cable duct cable duct
d 10 mm 8 mm 5 mm 0 mm
c 50 mm 38 mm 25 mm 0 mm
b 100 mm 75 mm 50 mm 0 mm
a 300 mm 225 mm 150 mm 0 mm
a) Shield performance (0 MHz to 100 MHz) equivalent to welded mesh steel basket of mesh size 50 mm × 100 mm (excluding ladders). This
shield performance is also achieved with a steel tray (cable unit without cover) of less than 1.0 mm wall thickness and / or more than 20 %
equally distributed perforated area.
b) Shield performance (0 MHz to 100 MHz) equivalent to a steel tray (cable unit without cover) of at least 1.0 mm wall thickness and no more
than 20 % equally distributed perforated area. This shield performance is also achieved with shielded power cables that do not meet the
performance defined in footnote d).
c) The upper surface of the installed cables must be at least 10 mm below the top of the barrier.
d) Shield performance (0 MHz to 100 MHz) equivalent to a steel conduit of 1.5 mm wall thickness. The separation specified is in addition to
that provided by any divider / barrier.
Table 8.2.5.1 Separation of telecommunications and low-voltage lines according to EN 50174-2, Table 4: “Minimum separation s”

not in agreement in agreement recommended
(arrangement of the
limitation compartments can be reversed)
(e.g. cable tie)

power supply
cables

auxiliary
or circuits

Power supply cables
Auxiliary circuits (e.g. fire information
alarm systems, door openers) technology cables
Information technology cables
or
cover (if required
Fallible circuits (e.g. measure- for fallible circuits) fallible
ment, instrumentation) circuits
Note: All metal parts
are (electrically) bonded
as described in section 5.
cover (if required
for fallible circuits)

Figure 8.2.5.5 Separation of cables in cable duct systems

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