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TVS 2000V Lightning and Surge Protection Feature Guidelines
This product includes TVS plate lightning protection technology to prevent damage caused by a pulse
signal that is below 3000 watts from sources such as lighting, surging, etc. Protection measures must be
taken to ensure electrical safety.
•
The distance between signal transmission line and high-voltage equipment or high-voltage cable
is at least 50 m.
•
Outdoor wiring should better be along the eaves as much as possible.
•
In the open field, wiring should be buried underground in sealed steel pipe with one-point
grounding. Overhead routing method is not acceptable.
•
In regions with thunderstorms or where high induction voltage are present (such as high-voltage
transformer substation), high power lightning protection apparatus and lightning conductor are
necessary.
•
The design for installation and wiring with lightning protection and grounding should be combined
with the lightning protection consideration of the building, and conform to the relevant national
and industry standards.
•
The system should ensure equipotential grounding. Grounding equipment must satisfy both system
anti-jamming and electric safety. It must not allow short circuit and open circuit with the zero
conductor of strong grid. When the system is singularly ground, the resistance must less than 4 Ω
and the cross-sectional area of the grounding cable must be no less than 25 mm
2
. For grounding
instructions, refer to local electrical codes and this manual.
Lightening rod
Communicate
arrester
Video arrester
Power arrester
45
°
conical
envelope
The resistance of
earthing conductor
must be less than 4 Ω.
The camera should be
within a 45
°
envelope
under the lightening rod.
Steel jacket
Lightning & Surge Protection
Wire gauge standards
Bare Wire Gauge(mm)
American Wire Gauge
(AWG)
Cross-sectional Area of
Bare Wire (mm
2
)
0.750
21
0.4417
0.800
20
0.5027
0.900
19
0.6362
1.000
18
0.7854
1.250
16
1.2266
1.500
15
1.7663
2.000
12
3.1420
2.500
4.9080
3.000
7.0683
12 Vdc Wire Gauge and Transmission Distance
The following table shows the recommended maximum distance adopted for the different wire sizes when
the 12 Vdc voltage loss is less than 15%. For example, for a device with the rating power of
20 VA which is installed 77 feet (22 m) from the transformer, the minimum wire gauge required is 1.0000
mm (18 gauge).
Power (VA)
Wire size mm (gauge)
0.800 (20)
1.000 (18)
1.250 (16)
2.000 (12)
10
97 (28)
153 (44)
234 (67)
617 (176)
20
49 (14)
77 (22)
117 (33)
308 (88)
24
41 (12)
64 (18)
98 (28)
257 (73)
30
32 (9)
51 (15)
78 (22)
206 (59)
40
24 (7)
38 (11)
59 (17)
154 (44)
48
20 (6)
32 (9)
49 (14)
128 (37)
50
19 (6)
31 (9)
47 (13)
123 (35)
60
16 (5)
26 (7)
39 (11)
103 (29)
70
14 (4)
22 (6)
33 (10)
88 (25)
80
12 (3)
19 (5)
29 (8)
77 (22)
90
10.8 (3.1)
17 (5)
26 (7)
69 (20)
100
9.7 (2.8)
15 (4)
23 (7)
62 (18)
110
8.9 (2.5)
14 (4)
21 (6)
56 (16)
120
8.1 (2.3)
13 (4)
20 (6)
51 (15)
130
7.5 (2.1)
11.8 (3.4)
18 (5)
47 (14)
140
7 (2)
11 (3.1)
17 (5)
44 (13)
150
6.5 (1.9)
10.2 (2.9)
16 (4)
41 (12)
160
6.1 (1.7)
9.6 (2.7)
15 (4)
39 (11)
170
5.7 (1.6)
9 (2.6)
14 (4)
36 (10)
180
5.4 (1.5)
8.5 (2.4)
13 (4)
34 (10)
