A Guide to BS EN 62305:2006 Protection Against Lightning Part 4 pps

... termination network Connection to air termination network Reference plane Catenary conductors (air termination) BS EN 62305-3 Physical damage to structures and life hazard h Physical height of catenary conductors above ... be spaced not more than 10m apart and if strike plates are used as an alternative, these should be strategically placed over the roof area not more than 5m apart...

Ngày tải lên: 08/08/2014, 13:21

... that in the event of lightning currents flowing, no metallic part is at a different voltage potential with respect to another. If the metallic parts are essentially at the same potential then ... this guide. Figure 4. 40 (based on BS EN 62305-3 fig E .45 ) shows a typical example of an equipotential bonding arrangement. The gas, water and central heating system are all bonded...

Ngày tải lên: 08/08/2014, 13:21

... transient overvoltages and transient currents) as well as radiated electromagnetic field effects. BS EN 62305 -4 is an integral part of the complete standard. By integral we mean that following a ... generally substantial enough to carry partial lightning currents, telecommunication lines have significantly smaller cross-sectional areas. Taking this factor into account, the worst...

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... materials are considered. Suburban environment Area with a medium density of buildings. ”Town outskirts” is an example of a suburban environment. Surge Transient wave appearing as overvoltage ... current attains 10% of its peak value. Voltage switching type SPD SPD that has a high impedance when no surge is present, but can have a sudden change in impedance to a low value in res...

Ngày tải lên: 08/08/2014, 13:21

... the standard. Part 2: Risk management BS EN 62305-2 (part 2) risk management approach, does not concentrate so much on the purely physical damage to a structure caused by a lightning discharge, ... European Union (EU), particularly relating to standardisation. Consequently, any British Standard now published has to be in common agreement with its European equivalent. The UK...

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... national parameters and information. These National Annex tables are highlighted later in this guide. One of the first changes to realise is that this new approach to risk management looks at ... at risk in a far broader sense than merely the physical damage that can be caused to a structure by a lightning discharge. BS EN 62305-2 Risk management BS EN 62305-1 | Type o...

Ngày tải lên: 08/08/2014, 13:21

... BS 6651 has a flash density map and a world thunderstorm day's map along with an accompanying table. These have been transferred to BS EN 62305-2, and also illustrated in this guide. See ... increasing importance given to the protection against LEMP (Lightning Electromagnetic Impulse), which can cause immeasurable and irreparable damage (as well as disastrous conseque...

Ngày tải lên: 08/08/2014, 13:21

... 5.5: Ideal Faraday Cage Lightning current Continuous metal box - ideal Faraday Cage Figure 5.6: Large volume shield created by metal reinforcement within a structure (BS EN 623 04- 4 Figure A. 3) Welded ... 0 A ) Foundation earthing electrode Bonding terminals LPZ 0 B LPZ 0 A Management of an LPMS As detailed in BS EN 62305-3, there is a requirement to routinely maintain...

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... documentation. The documentation should be continuously updated, particularly to take account of alterations to the structure that may require an extension of the LPMS. Summary Damage, degradation ... electrical contractor may add a power supply line to external CCTV cameras or car park lightning. As this line is likely to cross an LPZ, suitable protection measures (eg SPD) shou...

Ngày tải lên: 08/08/2014, 13:21

... of flashes) in accordance with Annex A of BS EN 62305-2. The calculated values are summarised in Table 6.18. Probability of damage Ascertain the probability of each particular type of damage ... x 10 -5 R Z2(T) N /A N /A 4. 477 x 10 -5 4. 477 x 10 -5 4. 477 x 10 -5 1. 343 x 10 -4 Total N /A N /A 4. 178 x 10 -4 3.931 x 10 -4 3.931 x 10 -4 1.2 04 x 10 -3 RR 2 4...

Ngày tải lên: 08/08/2014, 13:21