Lightning Standard Evolution:

Lightning Standard Evolution:
(BS) CP326 1965
BS6651
1985
BS6651
1992
Appendix C – equipment protection added
BS 6651
1999
BS EN 62305 Part 1 – 4 : 2006 International standards
BS EN / IEC 62305: Part 1 – 4: 2007
Part 1 – General Principles
Part 2 – Risk Management
Part 3 – Physical damage to
structures and life hazards
Part 4 – Electrical and electronic
systems within structures
Key changes: BS 6651 and BS EN 62305
BS 6651
BS EN 62305
Simple Risk Assessment provided with
basic guidelines given but owners to decide
based on self evident situations
(structural damage only)
Comprehensive Risk Management calculation
based on characteristics of structure such as type of
construction, contents, type of service and presence
of people.
(resulting in FOUR classes of LPS)
Annual testing and maintenance recommended
as a matter of practice but not integrated into
owners maintenance cycle.
Maintenance and testing cycle to be established in
the design of new LPS and through a lightning audit
for existing facilitites. LPS forms part of the client’s
planned maintenance programme.
Transient Overvoltage (Surge) protection in
Appendix C (informative)
Transient Overvoltage (Surge) protection
incorporated in main standard – detailed in
BS EN 62305-4
Components made from materials of
dimensions in accordance with Tables 2-4 in
Section 7
Components made and tested in accordance with
BS EN 50164 standard
IEC 62305 / BS EN 62305
Part 1:
General Principles
It introduces terms and definitions,
lightning current parametes, damages
due to lightning, protection needs and
measures, basic criteria for protection
of structures and services as well as
test parameters simulating the effects
of lightning on LPS components…
62305-1: General principles
Cows died due to
lightning strikes…
62305-1: General principles
Injuries caused by lightning
flowing in human bodies
62305-1: General principles
HUMAN LIVES TAKEN…
The late Mr Tiong & Mr Wong discovered it too late, they were killed by
lightning at RJCC for taking shelter under a shed with no LPS…
Tiong: Played a round of
golf every Thursday.
Wong: Was killed on
the spot.
62305-1: General principles
Tree barks split open
due to lightning strikes…
62305-1: General principles
Electronics damaged
due to lightning surges…
62305-1: General principles
The General principles includes:
4S – 3D – 4L
1.Lightning current as a SOURCE of damage to a STRUCTURE
and a SERVICE... S1, S2, S3 and S4.
2.Types of damage caused by lightning... D1, D2, and D3
3.Types of losses caused by lightning... L1, L2, L3 and L4.
62305-1: General principles
Source of damage
S1 – Flashes to the supplied structure or service
The structure risk components are classified as Ra, Rb and Rc
The service risk components are classified as R’v and R’w
62305-1: General principles
S2 – Flashes near the structure or service
Failure or malfunction of internal
systems due to LEMP
The structure risk components are classified as Rm
The service risk components are classified as R’z
62305-1: General principles
S3 – Flashes to a service connected to the structure
The structure risk components are classified as Ru, Rv and Rw
The service risk components are classified as R’b and R’c
62305-1: General principles
S4 – Flashes near a service connected to the structure
Failure or malfunction of internal
systems due to overvoltages induced
on connected lines and transmitted to
the structure.
The above structure risks component are classified as Rz
62305-1: General principles
Types of damage - Human
D1 – Injuries to living beings due to
step and touch voltages
62305-1: General principles
Types of damage - Physical
D2 – Physical damage (fire, explosion, mechanical
destruction etc) due to lightning current effects
including sparkling.
62305-1: General principles
Types of damage - Electronics
D3 – Failure of internal systems due to
lightning electromagnetic impulse (LEMP)
or surges.
62305-1: General principles
Types of LOSS:
L1 – loss of human life
Tolerable risk to be less than 1 in 100,000 as in table 7
Of BS EN 62305 Part 2: 2007
62305-1: General principles
Types of LOSS:
L2 – loss of service to the public
Tolerable risk to be less than 1 in 1,000 as in table 7
Of BS EN 62305 Part 2: 2007
62305-1: General principles
Types of LOSS:
L3 – loss of cultural heritage
Tolerable risk to be less than 1 in 1,000 as in table 7
Of BS EN 62305 Part 2: 2007
L4 – Loss of economic value
62305-1: General principles
LPZ (Lightning Protection Zone)
62305-1: General principles
Lightning Protection Zones
BSEN 62305
Part 2:
Risk Management
1.
2.
3.
4.
Hazard to a structure result in 3D
Consequential effects extend to
surroundings of structure
Protection measures required and to
be determined by risk assessment.
Protection may be taken regardless
of the outcome where there is a
desire that there be no avoidable
risk.
62305-2
62305-2
Probable average annual loss
L – is the type of loss as in Part 1
R– is the risk of loss and is the value of a
probable average annual loss...
R1 – risk of loss of human life or permanent injuries
R2 – risk of loss of services to the public
R3 – risk of loss of cultural heritage
R4 – risk of loss of economic value
R1
R2
R3
R3
62305-2
Summary of Risk components:
62305-2
62305-2
Collection area
Soil resisitivity
Insulation
Fire precautions
Special hazard
62305-2
1.
2.
3.
4.
5.
Risk management process:
Identification of risk components…Rx
Calculation of identified risks, Rx
Calculation of total risk, R
Identification of tolerable risk… Rt
Comparison of risk R with tolerable value Rt
If R < Rt, lightning protection not necessary
If R > Rt, protection measures to be taken
Click the link to connect to Jupiter software:
62305-2
Risk Management Procedure:
62305-2
Risk Management Procedure:
62305-2
Risk Management Procedure:
In Malaysia, the ave no of days with lightning from 2000 to 2011
is 240 which is equivalent to 40 strikes per sq. km per year.
Lightning Threats (2000-2011)
Pulau Langkawi (154)
Alor Setar (203)
Kota Bharu (187)
Kuala Krai (181)
Kuala Trengganu (214)
Butterworth (219)
Bayan Lepas (248)
Ipoh (134)
Cameron Highland (72)
Sitiawan (239)
Kuantan (192)
Kuala Lumpur (280)
Subang (267)
Petaling Jaya (71)
Temerloh (178)
Muadzam Shah(199)
Mersing (220)
Melaka (229)
Kluang (167)
Senai (125)
* Source :
Meteorological Department, Malaysia.
62305-3
Part 3:
Physical damage
to structures and
life hazard
FIVE TOPICS OF PART 3:
•Class of LPS
•Internal LPS
•External LPS
•Natural components
•Maintenance & inspection
62305-3
Class of LPS:
62305-3
BS 6651:1999
BS EN 62305:2006
Two levels of lightning
protection – ordinary and high
risk
Four levels of Lightning Protection
System (LPS)
I-IV
Class
I
II
III
IV
Mesh Size
(m x m)
5x5
10 x 10
15 x 15
20 x 20
DC spacing
Rolling
(m)
Sphere (m)
10
10
15
20
20
30
45
60
Faraday Cage 62305 principle
62305-3
Internal LPS:
Internal lightning protection systems
are meant to prevent the occurrence
of dangerous sparking within the
structure to be protected due to
lightning current flowing in the
external LPS of the structure.
62305-3
External LPS:
External lightning protection
systems consists of the:
-Air termination networks
-Down conductors
-Earth termination networks
and
-Equipotential bonding.
62305-3
Down Conductors
Natural
Components
62305-3
Most common form
- copperbond earth/ground rod (Type A method BSEN62305)
Lightning and Earthing Materials
62305-3
Natural components:
Natural components are:
1.Metal installations with overall electrical
resistance not greater than 0.2 ohms.
2.Metal of the electrically continuous
reinforced concrete framework of
structure
62305-3
Natural components:
Natural components are:
1. The interconnected steel framework of
the structure
2.The façade elements
3. Profile rails.
62305-3
The buildings (1) and the
tower (2) and the standalone equipment (3) and
the cable trenches (4) are
all interconnected to give
a low impedance earthing
System.
Earth mesh of a plant:
62305-3
Maintenance & Inspection of LPS:
Various types air finials/earth pits and their typical state of corrosion/damage:
Lightning conductor placed incorrectly.
Earth rod without earth pit installation
Corroded air finial base – poor contact
Damaged earth pit .
Water seepage down the imbedded conductor
Loose earth pit on turf area.
62305-3
Maintenance & Inspection of LPS:
Various types of test points and their typical state of corrosion/damage:
Round test point with missing bolts/nuts
Signs of corrosion due to water seepage
Imbedded test point with square clamp?
Corroded round test clamp on site
Badly corroded test point - water seepage
Lightning conductor loosed from clamp
62305-3
Earthing , Lightning and TokaiWeld Materials
62305-3
Maintenance & Inspection of LPS:
62305-3
Maintenance & Inspection of LPS:
62305-3
Maintenance & Inspection of LPS:
BSEN 62305
Part 4:
Electrical and electronic
systems within structures