 Stretched Line Method is formed by bonding a stretch wi re between the poles constructed two or more sides of the building, from a height that will take the building into protection. The poles must provide electrical continuity between the earthing of the stretch wire and poles. Besides, the stretch wire must be in a section that can carry the lightning current (minimum 50 mm2). It is not a common method due to the difficulty in application on tall buildings and the unattractive appearance on the building. |
|
Stretched Line Protection Cone Top Half Angles
|
Protection Level
|
a Angle
|
H ( Height)
|
|
20m
|
30m
|
45m
|
60m
|
|
Level - 1
|
a
|
25
|
*
|
*
|
*
|
|
Level - 2
|
a
|
35
|
25
|
*
|
*
|
|
Level - 3
|
a
|
45
|
35
|
25
|
*
|
|
Level - 4
|
a
|
55
|
45
|
35
|
25
|
|
|
|
|
|
|
|
