This document discusses standards for earthing and lightning protection of electrical systems. It covers the scope of IS/IEC 62305 in providing design, installation, inspection, maintenance and testing guidelines for lightning protection of electrical and electronic systems within structures. The standards aim to mitigate risks of permanent equipment failures due to lightning electromagnetic impulses. It does not cover protection against electromagnetic interference issues.

1. EARTHING STANDARDS
EARTHING STANDARDS
PROTECTION OF ELECTRICAL
SYSTEMS AS PER IS/IEC 62305-4

2. EARTHING STANDARDS
EARTHING STANDARDS
Protection against Lightning-
Electrical & Electronic systems
“within” structures- IS / IEC
62305
 Scope of Work : Provides information for the DESIGN, INSTALLATION, INSPECTION,
MAINTENANCE & TESTING of LPMS for Electrical & Electronic systems within
a structure, able to the risk of permanent failures due to lightning EM
Impulse.
 Not in Scope : This standard does not cover protection against
of electronic systems, which is due to EM interference.
(refer IS/IEC 60364-4-44 & IEC 61000 series)

3. EARTHING STANDARDS
EARTHING STANDARDS
History of EMC

4. EARTHING STANDARDS
EARTHING STANDARDS
Difference between Transient
Surge & Other Disturbances

5. EARTHING STANDARDS
EARTHING STANDARDS
Electrical & Electronic
Equipment

6. EARTHING STANDARDS
EARTHING STANDARDS
Protection against Lightning-
Electrical & Electronic systems
“within” structures- IS / IEC
62305
The need for this International Standard has arisen due to the
of electrical & electronic system, caused by Electro Magnetic effects of
Lightning. because, milli- joules of
Energy is sufficient to cause damage, whereas lightning flashes releases
Hundreds of mega joules of energy..

7. EARTHING STANDARDS
EARTHING STANDARDS
CEA Emphasizing on SPD

8. EARTHING STANDARDS
EARTHING STANDARDS
NBC Emphasizing on SPD

9. EARTHING STANDARDS
EARTHING STANDARDS
External & Internal LPS as per
IS/IEC 62305-4

10. EARTHING STANDARDS
EARTHING STANDARDS
External LPS reduces equipment
failure.. Page 68 of IS/IEC 62305-3

11. Office building
Examples of installations in use
1. Class I + II SPD
2. Class II SPD
required for line lengths > 10 m
2. Surge arresters B + C
3. Class III SPD
0
10
1
2
3
4
Sales
Sales

12. (Industrial plant)
Examples of installations in use
1. Class I + II SPD
2. Class II SPD
3. Appliance protection
Class III

13. EARTHING STANDARDS
EARTHING STANDARDS
Required Design Impulse
Voltage for Equipments (from
IEC 60364-4-443)

15. EARTHING STANDARDS
EARTHING STANDARDS
Connecting Wires
 If it is not possible to keep to the recommended line length of ≤ 0.25 m to the
arrester and from the arrester to the earthing point the surge protection
devices should not be connected with a spur line, but in a V-shape.
 Take care to run the outgoing and return lines as far apart as possible.

16. EARTHING STANDARDS
EARTHING STANDARDS
NBC 2016 EXTRACT

17. EARTHING STANDARDS
EARTHING STANDARDS
Safe & Failure Modes

18. EARTHING STANDARDS
EARTHING STANDARDS
SPD Selection Criteria
 Voltage Protection level - 'Lower' is better for the connected
equipment
 Surge current withstanding capacity
 Response of SPD
 Encapsulated, non-exhaustive spark gap
 Co-ordinated SPD Protection
 Compliance to latest IEC standards

19. EARTHING STANDARDS
EARTHING STANDARDS
Equipotential Bonding

20. EARTHING STANDARDS
EARTHING STANDARDS
Grounding- Vital for
protection load - Disastrous
Connection!

21. EARTHING STANDARDS
EARTHING STANDARDS
Grounding- Vital for
protection load - Common &
Preferred

22. EARTHING STANDARDS
EARTHING STANDARDS
UPS Protection
UPS is vulnerable to surges due to 3 reasons:
is micro-processor controlled device , the damage of
which prevents changeover to the generator in case of mains power failure.
2. Failure of which run from auto transfer switch to generator (to
start the generator prior to operation of change over switch) leads to “NO
BACK UP SUPPLY” when UPS batteries dry out.
3. Front end of the UPS- is vulnerable to surges

23. EARTHING STANDARDS
EARTHING STANDARDS
Protection of Electronic
Systems

24. EARTHING STANDARDS
EARTHING STANDARDS
Need for SPDs…. Failures reported
in a refinery in Kerala, India
1. Tripping of variable Frequency Drives & other soft starters
2. Failure of Computers (which were off line !!??##)
3. Failure of VHF communication systems
4. Failure of Auto Tank gauging system
5. Failures of gas monitor systems
6. Failure of telephone exchange
7. Failure of palm vane access control reading system
8. Failure of fire alarm systems
9. Failure of I/O cards in Satellite rack rooms
10.Failure of Alarm cards in Gas turbine control panel
11.Communication failure of Hydrocom of MUG compressor
12.Failure of cards in blending system

25. EARTHING STANDARDS
EARTHING STANDARDS
Need for SPDs…. Failures reported
in a major Thermal Power Plant in UP,
India.
1. Card failure in telephone exchange
2. Analog Output (AO) card failure in BMS panel
3. IGBT failure in VFD
4. Thyristor failure in VFD
5. EEPROM corruption in GE Mark V governing system
6. Power supply failure in GE Mark V governing system
7. CPU, AI & Communication card failure in Boiler # 3 panel
8. Power supply & Communication card failure in Ash bund RF

26. EARTHING STANDARDS
EARTHING STANDARDS
Need for SPDs…. Failures reported
in a Spice ingredient plant in Kerala
1. Failure of PLC Power Supply & AO card
2. Failure of EPABX power supply & trunk line
3. Failure of motor break control in automatic flex door
4. Failure of UPS
5. Failure of Weigh bridge LOAD CELLS & DISPLAY
6. Failure of biometric access sensor card
7. Failure of router & Ethernet switches

27. EARTHING STANDARDS
EARTHING STANDARDS

28. Coupling of systems
A direct strike on a building with an
external lightning protection
installation
L1
L2
L3
PEN
Data line
5% of Iimp is through data lines
5% of Iimp is through data lines

29. EARTHING STANDARDS
EARTHING STANDARDS
Need for Data Line Protection

30. EARTHING STANDARDS
EARTHING STANDARDS
SDN with DSL: application

31. EARTHING STANDARDS
EARTHING STANDARDS
Star: application Ethernet 100BaseT

32. EARTHING STANDARDS
EARTHING STANDARDS
Tips for installation
§ Connection as close as possible to the device!
§ Use short wires for the connection!
Conductor length max. 0,5
m
Local earthing
point
Conductor length max. 0,5 m
Local earthing point
§ Connection as close as
possible to the device!
§ Use short wires for the
connection!
Connection to the earthing

33. Cable TV
amplifier

34. SPDs for Hazardous Area
amplifier

35. Safe & Hazardous Area
Protection
amplifier

36. Protection at both ends are
required (unlike
barriers/isloators)
amplifier

37. Field Transmitter Protection
amplifier

38. Field Transmitter Protection-
classification
amplifier

39. Need for Field Transmitter
Protector
amplifier

40. Protection of CCTV cameras &
DVR
amplifier

41. Weigh Bridge Protection
amplifier

42. Complete Protection
amplifier

43. All Power inputs of Electronic
module is protected by SPDs
amplifier

44. Only 1 Power input of Electronic
module is protected by SPD
amplifier

45. amplifier

46. amplifier

47. amplifier

48. amplifier

49. Installation - Important tips
amplifier

50. amplifier
• PREVENTION IS ALWAYS BETTER THAN CURE
• HENCE INSTALLATION OF PROTECTIVE DEVICES iS
WISE RATHER THAT TO REPENT AFTER THE
DAMAGE.