Furuno 9ZWWR2120, Руководство по установке

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S2E-17-0209_IM_WR2120_C
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3. Solution: Ways to make a current installation safer
Lightning protection level definition
Lightning protection level (LPL) is defined in the regulation based on peak current. LPL will be selected
for installation situations where LPL IV is generally used. Protection area will be made using rolling
sphere, its radius is determined in the Table A-7. Example of an actual condition is shown in the Figure
A-3.
Table A-7: Probability and rolling sphere radius for LPL (IEC 62305-1)
LPL Probability
for min value
Minimum
peak
current [kA]
Probability
for max value
Minimum peak
current [kA]
Rolling
sphere
radius [m]
I 0.99 3 0.99 200 20
II 0.97 5 0.98 150 30
III 0.91 10 0.95 100 45
IV 0.84 16 0.95 100 60
Figure A-3: Protection of aerials and other external equipment (IEC 62305-4)
Key
1) lightning rod
2) steel mast with antennas
3) handrails
4) interconnected reinforcement
r) radius of the rolling sphere
Key
1) Lightning rod
2) Steel mast with antennas
3) Handrails
4) Interconnected reinforcement
r) Radius of the rolling sphere