Furuno 9ZWWR2120, Руководство по установке

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S2E-17-0209_IM_WR2120_C
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The collection extends to a line located at a distance of 500 m from the perimeter of the
structure:
where length L and width W of the structure are expressed in meter. Therefore the and
will be leaded as follows:
2.2.2.3. Assessment of the average annual number of dangerous events due to flashes to a line
Therefor for CWRP condition,
2.2.2.4. Assessment of the average annual number of dangerous events due to flashes near a line
Therefor for CWRP condition,
2.2.3. Assessment of probability of damage
The probabilities are given in the Annex B of IEC 62305-2. Based on practical condition, the values
are shown in the Table A-2.
Table A-2: Values of probability depending on the protection measures to reduce physical damage
2.2.4. Assessment of amount of loss
The values of amount of loss should be evaluated and fixed by the lightning protection designer
(or the owner of the structure). The typical mean values of loss in a structure given in the Annex
C of IEC 62305-2 are merely values proposed by the IEC.
The loss refers to the mean relative amount of a particular type of damage for one dangerous
event caused by a lightning flash, considering both its extent and effects. The loss value varies
the type of loss considered the weather radar will be classified to L2 and L4.
Table A-3: Type of loss L2 and L4: Loss values for each type of damage
Type of damage
Loss D2 D3
L2
L4
where
is the typical mean relative value of all goods damaged by failure of internal systems (D3)
due to one dangerous event. It will be for structures of hospital, industrial, office, hotel and
commercial.
is the typical mean relative value of all goods damaged by physical damage (D2) due to one
dangerous event. It will be 0.5 for structures of hospital, industrial, museum and agricultural.
is the factor reducing the loss due to physical damage depending on the risk of fire. It will be
0 for the weather radar.
Finally, we can get the values as follows:
Characteristics of structure LPL
No protection device — 1 1 1 1 1 1
Protected by
required components
IV 0.2 0.05 1.04 x 10
-5
0.05 0.05 0.05
III 0.1 0.05 1.04 x 10
-5
0.05 0.05 0.05
II 0.05 0.02 4.15 x 10
-6
0.02 0.02 0.02
I 0.02 0.01 2.07 x 10
-6
0.01 0.01 0.01