LIGHTNING & LIGHTNING PROTECTION - ITS ?· lightning & lightning protection its heartland conference…

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  • LIGHTNING & LIGHTNING PROTECTION

    I T S H E A R T L A N D C O N F E R E N C EM A R C H 2 7 , 2 0 1 3

    B U D VA N S I C K L EL I G H T N I N G P R O T E C T I O N I N S T I T U T E

  • Lightning strikes the United States 20 million times each year.

    A bolt of lightning can generate heat in excess of 50,0000 F.

    Lightning travels 90,000 miles per SECOND.

    Ligh

    tnin

    g Fa

    cts

    & F

    igur

    es

  • Dev

    asta

    tion

  • Dev

    asta

    tion

  • Empi

    re S

    tate

    Bui

    ldin

    g

  • Wha

    t is

    Ligh

    tnin

    g?

  • Ana

    tom

    y of

    Lig

    htni

    ng

  • Neg

    ativ

    e Li

    ghtn

    ing

  • Pos

    itive

    Lig

    htni

    ng

  • Clo

    ud-to

    -Gro

    und

    Ligh

    tnin

    g

  • NASA Global Lightning 1995 -2002

  • Flas

    h D

    ensi

    ty M

    aps

    1996 -2004

  • Flas

    h D

    ensi

    ty M

    aps

    2009

  • lightning related Insurance Information Institute

    (I.I.I.)

    Annual property losses due to lightning in the

    United States exceeded $1.03 billion in 2010 (2011

    $.952 billion) I.I.I.

    213,000 insurance claims for lightning damage were

    paid in 2010, (186,000 in 2011) avg. claim up 5% -

    I.I.I.

    The FAA estimates that lightning costs the airlines

    $2 billion annually in operating costs and passenger

    delays.

    Lightning is the leading cause of all church fires.

    Lightning is one of the leading causes of weather

    Saf

    ety

    & E

    cono

    mic

    C

    onse

    quen

    ces

  • Ligh

    tnin

    g Pr

    otec

    tion

  • NFPA 780: Standard for the Installation of Lightning Protection Systems

    UL96A: Installation Requirements for Lightning Protection Systems

    LPI 175: Lightning Protection Institute Standard of Practice

    Inst

    alla

    tion

    Stan

    dard

    s

  • Strike Termination Devices

    Conductors

    Ground Terminations

    Bonding Connections

    Surge Protection Devices (SPD)

    Five

    Ele

    men

    ts

  • NFPA ROLLING SPHERESt

    rikin

    g D

    ista

    nce

    Stepped Leader

  • Corners, edges, ridges of structures naturally accumulate ions in the electrical field, so they are likely candidates for lightning attachments. Tall slender items disrupt the field in the same manner, releasing ions easily or providing leaders for the lightning stroke

  • National Geographic Photo

  • NFPA ROLLING SPHERESt

    rikin

    g D

    ista

    nce

  • EFFECTS OF CURRENT FLOW THROUGH A CONDUCTOR

    Current flow through an impedance leads to a voltage.An electric field (E) will develop.A magnetic field (B) will develop.Coupling (capacitive & inductive) can occur through these fields.

    Vo

    V

    I B

  • SIDEFLASH

    An electric field can develop between the conductor and nearby objects, at different electrical potential.Once the field value exceeds a breakdown value, Ebr, sideflash, or arcing, can occur.Air breakdown:Ebr ~ 1 MV/m

    Vo

    V

    I VoE

    r

  • BONDING

    Ideal electrical connection results in equipotential. Since no electrical potential (voltage) difference exists, no field is developed, preventing flashover.In reality, connection is imperfect (since bonding conductor has impedance) so field will be minimized.

    Vo

    V

    I V

  • HOW SURGE OCCURS MAGNETIC FIELD COUPLING

    Service conductors in a magnetic field can have a current (and consequently a voltage) induced upon it, particularly if its parallel to the current path.

    Vo

    V

    I

    B

    Ii

  • OPERATION OF THE GROUNDING SYSTEM

    GROUNDING ELECTRODE (GROUND ROD)

    CONDUCTOR

    GRADE

    Consider current injection into the grounding electrode.

    I

  • OPERATION OF THE GROUNDING SYSTEM

    GRADE

    I

    CURRENT FLOWS THROUGH SHELLS OF EARTH, EACH WITH A RESISTANCE.I I

    RR R R R R R R

    v v v vvv v v

    A VOLTAGE DEVELOPS ACROSS EACH SHELL

  • OPERATION OF THE GROUNDING SYSTEM

    GRADE

    I

    I I

    RR R R R R R R

    v v v vvv v v

    STEP POTENTIAL V1 V2

  • GRADE

    V

    HOW SURGE OCCURS GPR EFFECTS

    V1 V2

    Unbonded grounding systems can develop severe voltage differences. If connected within a structure, very high currents can develop leading to magnetic coupling or arcing within equipment.

  • Pers

    onal

    Saf

    ety

  • Step Voltage

  • AVERAGE NUMBER OF U.S. LIGHTNING DEATHS*SINCE THE CAMPAIGN BEGAN (2000)

    50

    55

    60

    65

    70

    75

    00 01 02 03 04 05 06 07 08 09 10 11 12

    Deaths

    Year

    *30-year average

  • 2012 Lightning Deaths: A Closer Look

    89% were male 6 were children 7 were on fishing trips 7 left safe shelter or were steps

    away 6 were in or near water 12 were under or near trees Many were resuscitated but died

    later

    Lightning Deaths in 17 States

  • Leon

    the

    Lig

    htni

    ng L

    ion

  • The

    End

    Phone: 800-488-6864 E-mail: LPI@lightning.org Website: www.lightning.org

    BudVanSickleLightningProtectionInstitute

    QualityProgramGeneral Examprogramforcertification LPIIPfieldinspectionprogram 4Nationaltradeshows A&EinformationCD NFPA,ULSTP,IECCommittees AnnualConference Researchfunding LPI175Installation&177

    InspectionStandards

    Communication Newsletters&Eblasts Brochures&materials Featurearticles DVDsinfomercials Releasesonnationalwireservices LightningSafetyAwarenessWeek Leonthelightninglion I.I.I.,IBHS,&FLASH insurance

    industry

    Website FindanInstaller FAQ Links Specifications

    Researchpapers Noncompliantsystems Educationaltools Childrenssection Store Blog

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