A Guide to BS EN 62305:2006 Protection Against Lightning Part 10 ppsx

... 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 re...

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...

Ngày tải lên: 08/08/2014, 13:21

... later in this guide. One of the first changes to realise is that this new approach to risk management looks at risk in a far broader sense than merely the physical damage that can be caused to ... National Annexes NB, NC, and NH in preference to Annex B, C and H. Additionally Annex NK relates to the inclusion of other national parameters and information. These National Annex t...

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

... plane Catenary conductors (air termination) BS EN 62305-3 Physical damage to structures and life hazard h Physical height of catenary conductors above the reference plane s Separation distance p Penetration ... sphere radius Catenary conductors (air termination) Space protected by two parallel catenary conductors Connection to air termination network Connection to air terminati...

Ngày tải lên: 08/08/2014, 13:21

... electrical insulation distance between the metallic parts can avoid dangerous sparking between different metallic parts. BS EN 50164-1 is a performance specification. It attempts to simulate actual ... metallic installations/parts, such that in the event of lightning currents flowing, no metallic part is at a different voltage potential with respect to another. If the metalli...

Ngày tải lên: 08/08/2014, 13:21

... 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 risk assessment as detailed in BS EN ... earthing will achieve an area of equal potential, ensuring that electronic equipment is not exposed to differing earth potentials and hence resistive transients. A “Type B” earthin...

Ngày tải lên: 08/08/2014, 13:21

... 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 and inspect a structural LPS to ensure its designed mechanical and electrical characteristics ... 5.7 shows a large loop area created between power and data communication cabling. Figure 5.7: Loop areas Good practice Bad practice Area of...

Ngày tải lên: 08/08/2014, 13:21

... 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 ... that there are no alterations or additions to an installation, which may compromise the effectiveness of the LPMS. For example, an electrical contractor may add a power supply line to...

Ngày tải lên: 08/08/2014, 13:21

... 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 occurring ... the absence of any information relating to the time that occupants are in a hazardous place with respect to step and touch potentials, L t1 will be determined by multiplying the va...

Ngày tải lên: 08/08/2014, 13:21