| EXTERNAL LIGHTNING ARRESTERS |
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| What is EXTERNAL LIGHTNING PROTECTION ? |
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The main and most effective measure for protection of structures against physical damage is considered to be the Lightning Protection System (LPS). It usually consists of both external and internal lightning protection systems.
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An external LPS is intended to |
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Intercept a direct lightning flash to the structure (with an air-termination system) |
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conduct the lighting current safely towards earth (using a down-conductor system) |
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disperse the lightning current into the earth (using an earth-termination system) |
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Main protection measures against injury to living beings due to touch and step voltages are intended to |
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Reduce the dangerous current flowing through bodies by insulating exposed conductive parts, and/or by increasing the surface soil resistivity. |
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Reduce the occurrence of dangerous touch and step voltages by physical restrictions and/or warning notices |
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The type and location of an LPS should be carefully considered in the initial design of a new structure, thereby enabling maximum advantage to be taken of the electrically conductive parts of the structure. By doing so, design and construction of an integrated installation is made easier, the overall aesthetic aspects can be improved, and the effectiveness of the LPS can be increased at minimum cost and effort. |
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| Access to the ground and the proper use of foundation steelwork for the purpose of forming an effective earth termination may well be impossible once construction work on a site has commenced. Therefore, soil resistivity and the nature of the earth should be considered at the earliest possible stage of a project. This information is fundamental to the design of the earth-termination system and influence the foundation design work for the structure. |
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Regular consultation between LPS designers and installers, architects and builders is essential in order to achieve the best result at minimum cost. |
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If lightning protection is to be added to an existing structure, every effort should be made to ensure that it conforms to the principles of the standard. The design of the type and location of an LPS should take into account the features of the exiting structure. |
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| Storm detector |
The system is based on the measurement of electrostatis field.This measurement represents the electrical activities. of a storm in which there may be a risk of lightning strike.
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| Electrostatic Field |
The electrostatic field on the earth surface has magnitude of the order of 150 V/m in
good weather conditions |
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| The formation of electric charge in storm clouds modifies the value of this field.
Measuring the electrostatic field follows |
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To evauate the risk of atmospheric discharge. |
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To study the storm's behaviour (electrical charge) |
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To study the electrical field behaviourunder different conditions. More … |
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| PDC Stream lightning rod |
Through its latest generation early streamer emission (ESE) system, PDC Stream reaches a significant reduction in the time of upward emission (ionisation of the air around capture device). So, the speed and the efficiency of the electro atmospheric discharges capture increases and, consequently, the protection area becomes bigger |
| Protection Areas |
| We obtain the Early Streamer Emission time (t) through the laboratory tests (UNE 21186, annex C). Then, applying the formulas and prescriptions of different norms, we can calculate the radius of the protection area of each model. |
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| In Spain the valid law is, from October 2006, the Código Técnico de la Edificación which give us the following results for INGESCO® PDC Stream |
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STREAM-15 |
STREAM-30 |
STREAM-45 |
STREAM-60 |
| LEVEL I (D=20 m) |
35 m |
50 m |
65 m |
80 m |
| LEVEL II (D=30 m) |
45 m |
60 m |
75 m |
90 m |
| LEVEL III (D=45 m) |
60 m |
75 m |
90 m |
105 m |
| LEVEL IV (D=60 m) |
75 m |
90 m |
105 m |
120 m |
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Internationally, the reference norm is NFC 17 102 which give us the following results for INGESCO® PDC Stream. |
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STREAM-15 |
STREAM-30 |
STREAM-45 |
STREAM-60 |
| LEVEL I (D=20 m) |
35 m |
50 m |
65 m |
80 m |
| LEVEL II (D=45 m) |
54 m |
70 m |
86 m |
102 m |
| LEVEL IV (D=60 m) |
63 m |
81 m |
97 m |
113 m |
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| PDC-E lightning rod |
It is a high quality lightning rod with the most competitive price. it is the result of a long experience in manufacturing and installing ligthning protection systems and it takes also advantage of a constant research in materials and devices resistance. |
| Protection Areas |
We obtain the Early Streamer Emission time (Dt) through the laboratory tests (UNE 21186, annex C). Then, applying the formulas and prescriptions of different norms, we can calculate the radius of the protection area of each model. |
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| In Spain the valid law is, from October 2006, the Código Técnico de la Edificación which give us the following results for INGESCO® PDC-E |
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PDC-E 15 |
PDC-E 30 |
PDC-E 45 |
PDC-E 60 |
| LEVEL I (D=20 m) |
35 m |
50 m |
65 m |
80 m |
| LEVEL II (D=30 m) |
45 m |
60 m |
75 m |
90 m |
| LEVEL III (D=45 m) |
60 m |
75 m |
90 m |
105 m |
| LEVEL IV (D=60 m) |
75 m |
90 m |
105 m |
120 m |
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| Internationally, the reference norm is NFC 17 102 which give us the following results for INGESCO® PDC-E. |
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PDC-E 15 |
PDC-E 30 |
PDC-E 45 |
PDC-E 60 |
| LEVEL I (D=20 m) |
35 m |
50 m |
65 m |
80 m |
| LEVEL II (D=45 m) |
54 m |
70 m |
86 m |
102 m |
| LEVEL IV (D=60 m) |
63 m |
81 m |
97 m |
113 m |
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