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Lightning & Surge Protection
The product adopts multi-level anti-lightning and anti-surge technology integrated with gas discharge tube, power
resistor and TVS tube. The powerful lightning and surge protection barrier effectively avoids product damage
caused by various pulse signals with power below 4kV, including instantaneous lightning, surge and static.
However, for complicated outdoor environment, refer to instruction below for lightning and surge protection:
zThe product features with dedicated earth wire, which must be firmly grounded. As for surveillance sites
beyond the effective protection scope, it’s necessary to erect independent lightening rods to protect the security
devices. It’s recommended to separate the lightning rod from the mounting pole, placing the rod on an
independent pole, as shown in the figure below. If the product has to be installed on the same pole or pedestal
for lightning rod, there should be strict insulation between the video cable BNC terminal, power cable, control
cable and the standing pole of the lightning rod.
zFor suburb and rural areas, it’s recommended to adopt direct burial for the transmission cables. Overhead
wiring is prohibited, because it’s more likely to encounter lightning strike. Use shielded cables or thread the
cables through metal tubes for burial, thus to ensure the electric connection to the metal tube. In case it’s
difficult to thread the cable through the tube all the way, it’s acceptable to use tube-threaded cables only at both
ends of the transmission line, yet the length in burial should be no less than 15 meters. The cable sheath and
the tube should be connected to the lightning -proof grounding device.
zAdditional high-power lightning-proof equipment and lightning rods should be installed for strong
thunderstorm or high induced voltage areas (such as high-voltage substation).
zThe lightning protection and grounding for outdoor devices and wires should be designed in line with the
actual protection requirement, national standards and industrial standards.
zThe system should perform equipotential grounding by streaming, shielding, clamping and earthing. The
grounding device must meet anti-interference and electric safety requirements. There should be no
short-circuiting or hybrid junction between the device and the strong grid. Make sure there’s a reliable
grounding system, with grounding resistance below 4Ω(below 10Ωfor high soil resistivity regions). The
cross-sectional area of the earthing conductor should be no less than 25mm².
Lightning rod
Front device
for surveillance
system
Separated layout for the lightning
rod and the standing pole
LPZOB
LPZOA
Mounting
pole for
front device
30° 30°