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Appendix Ⅰ Thunder Proof and Surge Protection
This series speed dome adopts TVS lighting protection technology. It can effectively prevent damages from
various pulse signals below 4000V, such as sudden lighting and surge. While maintaining your local
electrical safety code, you still need to take necessary precaution measures when installing the speed dome
in the outdoor environment.
z
The distance between the signal transmission cable and high-voltage device (or high-voltage cable)
shall be at least 50 meters.
z
Outdoor cable layout shall go under the penthouse if possible.
z
For vast land, please use sealing steel tube under the land to implement cable layout and connects one
point to the earth. Open floor cable layout is forbidden.
z
In area of strong thunderstorm hit or near high sensitive voltage (such as near high-voltage transformer
substation), you need to install additional high-power thunder protection device or lightning rod.
z
The thunder protection and earth of the outdoor device and cable shall be considered in the building
whole thunder protection and conform to your local national or industry standard.
z
System shall adopt equal-potential wiring. The earth device shall meet anti-jamming and at the same
time conforms to your local electrical safety code. The earth device shall not short circuit to N (neutral)
line of high voltage power grid or mixed with other wires. When connect the system to the earth alone,
the earth resistance shall not be more than 4
Ω
and earth cable cross-sectional area shall below 25
mm2. See
Figure 7-1
.
Figure 7-1
