Planning of Lightning Protection · PDF filePlanning of Lightning Protection Systems ... The standard IEC 62305 was the basis for EN 62305 of CENELEC. National conditions were taken

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Planning of Lightning Protection SystemsDEHNsupport Toolbox Software

Complicated calculations are history. Today it‘s easier...

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Benefits of the DEHNsupport Toolbox software:

• user-friendly interface• structured customer and project management• detailed documentation of results• based on the international IEC 62305 standard• meets specific requirements of 13 national standards • 13 different languages• user support via e-mail and phone• product training available• good value for money

Update V3

...with DEHNsupport Tool-box SoftwareWhen planning lightning protection systems, various parameters must be taken into account, such as the building dimensions, electrical equipment, risk class-es or financial aspects. The DEHNsupport Toolbox software makes this complex topic simple as never before since it performs all calculations. The DEHNsupport Toolbox software consists of the following four parts:

DEHN Risk Tool page 4Risk management including a procedure for assessing the risk is an integral part of the IEC 62305 lightning protec-tion standard. DEHN Risk Tool makes risk management easier and ensures standard-compliant risk assessment in just a few steps.

The V3 update of the DEHNsupport Toolbox software includes a risk analysis according to edition 2 of the IEC 62305 standard and national adaptations.

DEHN Distance Tool page 10The separation distance defines the minimum distance of the lightning protection system from electrically conductive materials. If this separation distance is kept, dangerous sparking and uncontrolled flashover are prevented. DEHN Distance Tool allows to calculate the separation distance and to visualise the building as a 3D model.

DEHN Air-Termination Tool page 12 DEHN Air-Termination Tool allows to calculate the length of air-termination rods depending on the class of LPS (Lightning Protection System).

DEHN Earthing Tool page 13DEHN Earthing Tool allows to calculate the length of earth electrodes as per IEC 62305-3 – for every type of earth electrode and soil resistivity.

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Simple management of all customer dataThe DEHNsupport Toolbox software is based on a customer data and project management where all calculations are structured and permanently saved. These calculations can be retrieved and changed at a later date. Moreover, further customer or project data can be entered which are also included in the result report.

Ground flash density data The ground flash density, which is selected in the customer and project management data, is an important value for performing a risk analysis according to IEC 62305-2.

DEHN Risk Tool: Customer and project management

Country-specific adaptionsThe DEHNsupport Toolbox software includes ground flash density data and the associated maps for• Austria• Belgium• Czech Republic• Croatia• France• Germany• Great Britain• Hungary• Italy• Macedonia• Poland• Russia• Slovakia

Update V3

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Risk analysis according to IEC 62305-2

LPS = Lightning Protection SystemLEMP = Lightning Electromagnetic Pulse

Risk R1: Risk of loss of human life

Risk R2: Risk of loss of services to the public

Risk R3: Risk of loss of cultural heritage

Risk R4: Risk of loss of economic value

Photo: Lightning Protection Paul Hahl, Frankfurt

Risk management and assessment of the buildingA risk analysis is performed to assess the potential risk for a building. Based on this analysis, measures can be taken to reduce the risk. The aim is to select economically sound protection measures which are perfectly adapted to the building’s properties and type of use.

A risk analysis does not only allow to determine the class of LPS, but also to develop a complete protection concept including the necessary LEMP protection measures.

The aim of a risk analysis is to reduce the existing risk to a tolerable risk RT. Therefore, the tolerable risk RT is defined when selecting the risks. These tolerable risks are specified in the standard, however, responsible authorities having jurisdiction may define them in another way.

Risks to be consideredAt the beginning of a risk analysis, the type of building use is required to determine the risks to be considered for the object requiring protection.

When performing a risk analysis, four different risks are distinguished: • Risk R1: Risk of loss of human life• Risk R2: Risk of loss of services to the public• Risk R3: Risk of loss of cultural heritage• Risk R4: Risk of loss of economic value

One or more risks can be relevant. The planner has to decide which risks to select.

Human life Service to the public Cultural heritage Economic value

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Risk compositionWhen performing a risk analysis, not only the risks R1 to R4

are considered. Even more important is the composition of the total risk since each risk consists of individual risk components.

Subdivision of the risk components according to the sources of damageThe sources of damage form the basis for the sub-division of the risk components. The IEC 62305-2 standard describes different types of lightning effects as sources of damage. When performing a risk analysis, the following components are considered as sources of damage:

DEHN Risk Tool: Assessment and reduction of risks

Source of damage S1: Flashes to a structureRA = Step and touch voltage inside and outside a structureRB = FireRC = Overvoltage / LEMP

Source of damage S2:Flashes near a structureRM = Overvoltage / LEMP

Source of damage S3: Flashes to a lineRU = Touch voltage inside a structureRV = FireRW = Overvoltage

Source of damage S4: Flashes near a lineRZ = Overvoltage

LEMP = Lightning Electromagnetic Pulse

RW

RV

RU

RZ

S4

S1

RA

S3

RB

... to a structure

RC

... near a line

... to a line

Flashes...

Risk RX

RM

S2... near a structure

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Each risk component consists of different factors:

RX = NX x PX x LX

These factors are defined as follows:

NX = Number of dangerous events per annumPX = Probability of damage to a structureLX = Consequent loss

Frequency of dangerous events NX

A variety of parameters are required to calculate the fre-quency of dangerous events NX, for example: • Lightning ground flash density NG

• Collection area AD

• Location factor CD

• Environmental factor CE

Probability of damage PX

The probability PX describes the building and installation properties of a structure. These properties can reduce or increase the risk. Particularly the risk of fire, which defines the specific fire load of a structure, plays an important role when performing a risk analysis.

Loss LX

In addition to the frequency of dangerous events and the probabilities of damage, possible loss must also be cal-culated. Losses are differentiated according to the risks considered in the risk analysis and thus according to the risk components. The following losses can be determined:

L1 Loss of human life:• Touch and step voltage • Fire• Overvoltage / LEMP

L2 Loss of services to the public:• Fire• Overvoltage / LEMP

L3 Loss of cultural heritage:• Fire

L4 Loss of economic value:• Touch and step voltage • Fire• Overvoltage / LEMP

Urban environment: Ce= 0.01 Urban environment (buildings < 20.0 m) : Ce= 0.1

Suburban environment (e.g. in the outskirts): Ce= 0.5 Rural environment (e.g. small village) : Ce=1

LEMP = Lightning Electromagnetic Pulse

Environmen-tal factor

Ce

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Correct interpretation of the resultEach risk to be considered is displayed in a different colour. Blue stands for the tolerable risk, red or green for the risk calculated for the structure to be protected.

Determination of the potential risksThe risk components describe the potential risks for a structure. Therefore, the risk components must be considered in detail when performing a risk analysis. The aim of a risk analysis is to reduce the main risks by taking reasonable measures.

Determination of the main risksEach risk component can be reduced or increased by different parameters.

DEHN Risk Tool: Focus on cost-effectiveness

Selection of measures in the DEHN Risk ToolMeasures can be defined with the help of a selection matrix. These measures are displayed according to the risk components selected.

Cost-effectiveness of protection measuresBuilding owners are often faced with the question which damage can occur as a result of lightning effects and how high costs for protection measures should be with regard to the value of the building. Therefore, economic aspects are an important decision criterion. The risk analysis as per IEC 62305-2 integrated in the DEHN Risk Tool software provides a selection aid.

RT R1

RT R1

Without measures With measures

25238 % 61 %

2,52E-03 6,14E-061E-5 1E-5

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Country-specific normative adaptationsThe standard IEC 62305 was the basis for EN 62305 of CENELEC. National conditions were taken into consideration when adopting the EN 62305 as national standards by the CENELEC members.

Documentation and printoutCountry-specific standard designations and the associated national calculation values can be selected and displayed in the DEHN Risk Tool software. The results of the risk analysis can be printed as a summary or detailed report in the relevant language.

The DEHNsupport Toolbox software is specified for the following countries:• Austria• Belgium• Czech Republic• Croatia• France• Germany• Great Britain• Hungary• Italy• Macedonia• Poland• Russia• Slovakia

CENELEC: European Committee for Electrotechnical Standardisation, www.cenelec.eu

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Basic Version: Conventional calculation as per IEC 62305-3To prevent damage caused by lightning strikes, specific protection measures must be taken. Knowledge in the field of lightning research allowed to constantly further develop the method of calculating the separation distance.The current IEC 62305-3 standard points out that roof-mounted structures be located in the protected zone using air-termination rods or elevated air-termination systems (elevated ring conductor or spanned cables). To this end, the calculated separation distance s must be kept.

The following general equation is used to calculate s:

where• ki depends on the selected class of LPS

• km depends on the electrical insulation material

• kc depends on the (partial) lightning current flowing through the air-termination systems and down conductors

• l is the length along the air-termination system or down conductor from the point where the separation distance is to be determined to the nearest equipoten-tial bonding point or the earth-termination system.

The length l can be disregarded in structures with continu-ous metal roofs acting as natural down conductor.

Distance Edition: Calculation according to nodal analysisIn the Basic Version of the DEHN Distance Tool software, the separation distance is calculated with the help of an Excel table. The Basic Version can be upgraded to the Distance Version which allows to calculate the separation distance by means of nodal analysis.

Nodal analysis is a method for network analysis used in electrical engineering. A constant earthing resistance is assumed for the calculation (type B earth electrode).Nodal analysis provides more exact results than a conven-tional calculation according to the IEC 62305-3 standard.

DEHN Distance Tool: Separation distances

s = ki · · l (m)kc

km

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Lightning Protection Systemaccording to IEC 62305-3

sep

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dis

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Visualisation as a3D building model

Automatic calculation of the separation distance and visualisation as a 3D building modelTo facilitate the user’s work and to save time, building types can be selected from a picture gallery. After selecting and activating a building type, the dimensions of the building can be defined. The separation distances are calculated and visualised as a 3D building model after selecting the class of LPS.

Editing a LPSMesh sizes often cannot be kept and air-termination sys-tems have to be adapted to local conditions. The following changes can be made in the DEHN Distance Tool:

• inserting ring conductors• adding down conductors• inserting internal down conductors• inserting air-termination rods• inserting or deleting air-termination conductors and down conductors• shifting air-termination conductors and down conductors• shifting or raising the zero potential level• inserting measuring points• inserting points of strike• inserting texts and notes

Free layout of complex buildingsTo meet the requirements of complex buildings, DEHN Distance Tool allows to adapt a building complex to custom-er needs. Different annexes and roof-mounted structures can be integrated in this building.

LPS = Lightning Protection System

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DEHN Air-Termination Tool: Length of air-termination rods

Determining the length of air-termination rodsAir-termination rods allow to integrate large areas in the protected zone of LPZ 0B. DEHN Air-Termination Tool allows to determine the length of air-termination rods easily. In some cases, graphics, which must be created de-pending on the class of LPS, are required for this purpose. To facilitate work for qualified personnel, calculations for different kinds of graphics are integrated in the software.

Calculation options: 1. Protective angle method2. Rolling sphere method for one, two or four air-termination rods 3. Rolling sphere method for four air-termination rods on pitched roof surfaces

To ensure a technically correct external lightning protection system, the protected zones must be properly dimensioned according to the height of the air-termination rod.

LPS = Lightning Protection System

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DEHN Earthing Tool: Length of earth electrodes

Calculation of the length of earth electrodesThe DEHN Earthing Tool allows to calculate the length of earth electrodes as per IEC 62305-3. In this context, the different types of earth electrodes are important: Founda-tion earth electrode, ring earth electrode or earth rod. The soil resistivity is also an important factor for determining the required length of the earth electrodes.

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Increased know-how: DEHNsupport Toolbox seminarIn one to two-day seminars, you will become acquainted with the fundamentals of risk management as per IEC 62305-2. Besides theoretical knowledge, each seminar also includes different practical exercises using the DEHNsupport Toolbox. In addition, you will learn how to calculate the separation distance, the length of air-termina-tion rods and the length of earth electrodes. A computer with the relevant DEHNsupport Toolbox software version is available to each participant. This allows to directly apply the newly acquired skills in practice.

Seminars and support

The individual steps of a risk analysis are described in the brief instructions.

DEHNsupport Toolbox brief instructions

Our support is there for you!We are happy to assist you in case of application problems. Phone: +49 9181 906-1601. Monday to Friday from 8.00 a.m. to 4.00 p.m., CET.

Our support team provides assistance in case of technical problems. Phone: +49 9181 906-1594.Monday to Friday from 8.00 a.m. to 4.00 p.m., CET.

Send us your questions by e-mail to [email protected]

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Ordering information

Different versions of the DEHNsupport software are available:

DEHNsupport Basic Version software Including risk analysis, calculation of the length of the earth electrodes, calculation of the length of the air-termi-nation rods and conventional calculation of the separation distance. Price: EUR 180 (excl. VAT)

DEHNsupport Distance Edition software Including risk analysis, calculation of the length of the earth electrodes, calculation of the length of the air-ter-mination rods and calculation of the separation distance according to nodal analysis. Price: EUR 275 (excl. VAT)

Upgrade from Basic Version to Distance Edition An upgrade for calculating the separation distance accord-ing to nodal analysis is available for the Basic Version.Price: EUR 95 (excl. VAT)

Multi-user system The price of multi-user systems for more than two work-places depends on the number of users.

UpdatesWe will inform you about our free updates as soon as they are available.

Ordering informationThe DEHNsupport software can be directly ordered from DEHN. The product includes two single-user licences and can be installed on the server. Please also observe the instructions in the Help menu item of the software.

System requirements:Operating system:• Microsoft Windows XP® , Vista® , 7®, 8® or 8 Pro®

Minimum hardware requirements:• Intel®/AMD® processor or compatible processor• 500 MB free hard disc space• 1500 MHz, 1 GB RAM (Windows XP®)• 2000 MHz, 2 GB RAM (Windows Vista®)• 2000 MHz, 2 GB RAM (Windows 7®/8®)• Monitor resolution of 1024 x 768 pixels • 32 MB VGA graphics card• 100 MBit/s network connection for multi-user systems

Software:Microsoft Excel®

Test the DEHNsupport Toolbox and download the demo versi-on from our homepage.

DEHNsupport Toolbox

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DS709/E/1013 © Copyright 2013 DEHN + SÖHNE Titel: Lightning Photo by Michael Bath, www.lightningphotography.com

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