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Appendix III: Lightning Proof & Surge Proof
The product adopts TVS lightning proof technology to
prevent from damage by lightning strike below 4000V
and impulse signals such as surge; but it is also neces-
sary to abide by the following precautions to ensure elec-
trical safety based on practical circumstances:
Keep the communication cables at least 50 meters away
from high voltage equipment or cables.
Make outdoor cable laying-out under eaves as possible
as you can.
In open area shield cables in steel tube and conduct a
single point ground to the tube. Trolley wire is forbidden
in such circumstances.
In strong thunderstorm or high faradic zone (such as
high voltage transformer substation), extra strong light-
ning proof equipment must be installed.
Take the building lightning proof requirements into ac-
count to design the lightning proof and grounding of
outdoor equipment and cable laying-out in accordance
with the national and industrial standards.
The system must be grounded with equal potentials.
The earth ground connection must satisfy the anti-
interference and electrical safety requirements and
must not short circuited with high voltage electricity
net. When the system is grounded separately, the
impedance of down conductor should be less than 4
Ohms and the sectional area of down conductor
should be greater than 25 square mm (refer to fol-
lowing picture).
Li ghting rod
45 degree
Video cable
l ightning conductor
C ommunication cable
li ghtning conductor
Pow er cable
lightning conductor
The resistance
of down conductor
should be less than
4 ohm
S hi eld steel rube
