GB/T 38121-2023 Protection against lightning - Thunderstorm warning systems
1 Scope
This document describes the characteristics of thunderstorm warning systems (TWSs) in order to implement lightning hazard preventive measures.
Single sensors and/or a network of sensors (e.g. lightning location system) can be used as a TWS.
This document provides requirements for sensors and networks collecting accurate data of the relevant parameters, giving real-time information on lightning and atmospheric electric activity. It describes the application of the data collected by these sensors and networks in the form of warnings and historical data.
This document includes:
• a general description of available techniques for TWSs;
• guidelines for alarming methods;
• informative examples of possible preventive actions.
The following aspects are outside the scope of this document:
a) lightning protection systems: such systems are covered by IEC 62305 (all parts)[1];
b) other thunderstorm related phenomena such as rain, hail, wind;
c) satellite and radar based thunderstorm detection techniques;
d) portable devices (a device where the sensor is not fixed).
Note: It is possible that calibration and testing of portable devices will not be sufficient to provide efficient warning.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
IEC 60068-2-75:2014 Environmental testing - Part 2-75: Tests - Test Eh: hammer tests
Note: GB/T 2423.55-2006, Environmental testing for electric and electronic products - Part 2: Test methods - Test Eh: Hammer tests (IEC 60068-2-75:1997, IDT)
IEC 60529 Degrees of protection provided by enclosures (IP Code)
Note: GB/T 4208-2017, Degrees of protection provided by enclosure (IP Code) (IEC 60529:2013, IDT)
IEC 61000-6-4 Electromagnetic compatibility (EMC) - Part 6-4: Generic standards - Emission standard for industrial environments
Note: GB 17799.4-2022, Electromagnetic compatibility (EMC) - Generic standards - Part 4: Emission for industrial environments (IEC 61000-6-4:2018, IDT)
IEC 61180 High-voltage test techniques for low-voltage equipment - Definitions, test and procedure requirements, test equipment
Note: GB/T 17627-2019, High-voltage test techniques for low-voltage equipment - Definitions, test and procedure requirements, test equipment (IEC 61180:2016, MOD)
IEC 62561-1 Lightning protection system components (LPSC) - Part 1: Requirements for connection components
Note: GB/T 33588.1-2020, Lightning protection system components (LPSC) - Part 1: Requirements for connection components (IEC 62561-1:2017, IDT)
IEC 62561-4 Lightning protection system components (LPSC) - Part 4: Requirements for conductor fasteners
Note: GB/T 33588.4-2020, Lightning protection system components (LPSC) - Part 4: Requirements for conductor fasteners (IEC 62561-4:2017, IDT)
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC: http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1.1
alarm
information indicating that a defined area is likely to be affected by thunderstorms and the accompanying lightning related events (LREs)
3.1.2
cloud-to-ground lightning; CG
electric discharge of atmospheric origin that is comprised of one or more cloud-to-ground lightning strokes that propagate from cloud to ground or vice versa and lead to a net transfer of charge between cloud and ground
3.1.3
coverage area; CA
area where a given warning equipment has a sufficient detection efficiency (DE) and/or accuracy to give a warning
3.1.4
detection efficiency; DE
percentage of lightning discharges that is detected by a sensor or a network
3.1.5
effective alarm; EA
alarm where a lightning related event (LRE) occurs in the surrounding area (SA) during the total alarm duration (TAD)
Note: An effective alarm can only be assessed when LREs are monitored. When LREs are not monitored the lightning related conditions (LRC) may define a valid alarm, see Figure 3 a).
3.1.6
effective alarm ratio; EAR
number of effective alarms (EAs) with respect to the total number of alarms (TNA)
3.1.7
time to clear; TTC
time between the occurrence of the last lightning related event (LRE) in the monitoring area (MA) and the time when the alarm is released
3.1.8
failure to warn; FTW
occurrence of a lightning related event (LRE) in the surrounding area (SA) for which no alarm occurred
3.1.9
failure to warn ratio; FTWR
number of failures to warn with respect to the total number of situations with lightning related events (LREs) affecting the surrounding area (SA)
3.1.10
false alarm; FA
alarm when there is no thunderstorm activity in the monitoring area (MA)
Example: An alarm due to TWS equipment malfunction or an alarm triggered by any signal not related to thunderstorm (snow, sand, electromagnetic disturbances, etc.).
3.1.11
false alarm ratio; FAR
number of false alarms with respect to the total number of alarms (TNA)
3.1.12
electrostatic field sensor; EFS
device for continuous monitoring of the atmospheric electrostatic field, where the sensor is located, associated with thunderstorms
Example: An electric field mill.
Note: Also known as atmospheric electric field meter, atmospheric field strength meter or electrostatic field sensor.
3.1.13
intra-cloud lightning; IC
electric discharge of atmospheric origin occurring within or among thunderclouds or between thunderclouds and air and which does not have a ground termination
3.1.14
lead time; LT
time between the start of an alarm and the effective occurrence of the first lightning related
event (LRE) in the surrounding area (SA)
Note 1: Any efficient preventive action should be completed before the end of the lead time.
Note 2: A lead time can only be assessed when LREs are monitored. When LREs are not monitored the lightning related conditions (LRC) may define an estimated lead time, see Figure 3 a).
3.1.15
lightning related event; LRE
event where one or more cloud-to-ground lightning (CG) occurs inside the surrounding area (SA)
3.1.16
lightning related conditions; LRC
static electric field that has reached a level high enough so that lightning is expected to occur at any time in the surrounding area (SA)
3.1.17
median location accuracy
median value of the distances between real stroke locations and the stroke location given by a lightning location system
3.1.18
monitoring area; MA
geographic area where the lightning or upcoming lightning (lightning is expected to occur at any time) activity is monitored in order to provide a valid warning for the surrounding area (SA)
Note: The monitoring area is smaller or equal to the coverage area.
3.1.19
preventive action
action of a temporary nature, that should be completed before the end of the lead time (LT), taken on the basis of the preventive information and included in the emergency plans
3.1.20
surrounding area; SA
geographic area in which a lightning related event (LRE) causes a potential danger and which surrounds and includes the target (TA) to be protected
Note: Any lightning related event (LRE) occurring in the surrounding area (SA) is potentially dangerous for the target (TA). This area is used when evaluating a thunderstorm warning system (TWS) to determine the performance parameters such as failure to warn ratio (FTWR).
3.1.21
target; TA
object or area for which a thunderstorm warning is needed
Standard
GB/T 38121-2023 Protection against lightning—Thunderstorm warning systems (English Version)
Standard No.
GB/T 38121-2023
Status
valid
Language
English
File Format
PDF
Word Count
18500 words
Price(USD)
555.0
Implemented on
2023-12-1
Delivery
via email in 1~3 business day
Detail of GB/T 38121-2023
Standard No.
GB/T 38121-2023
English Name
Protection against lightning—Thunderstorm warning systems
GB/T 38121-2023 Protection against lightning - Thunderstorm warning systems
1 Scope
This document describes the characteristics of thunderstorm warning systems (TWSs) in order to implement lightning hazard preventive measures.
Single sensors and/or a network of sensors (e.g. lightning location system) can be used as a TWS.
This document provides requirements for sensors and networks collecting accurate data of the relevant parameters, giving real-time information on lightning and atmospheric electric activity. It describes the application of the data collected by these sensors and networks in the form of warnings and historical data.
This document includes:
• a general description of available techniques for TWSs;
• guidelines for alarming methods;
• informative examples of possible preventive actions.
The following aspects are outside the scope of this document:
a) lightning protection systems: such systems are covered by IEC 62305 (all parts)[1];
b) other thunderstorm related phenomena such as rain, hail, wind;
c) satellite and radar based thunderstorm detection techniques;
d) portable devices (a device where the sensor is not fixed).
Note: It is possible that calibration and testing of portable devices will not be sufficient to provide efficient warning.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
IEC 60068-2-75:2014 Environmental testing - Part 2-75: Tests - Test Eh: hammer tests
Note: GB/T 2423.55-2006, Environmental testing for electric and electronic products - Part 2: Test methods - Test Eh: Hammer tests (IEC 60068-2-75:1997, IDT)
IEC 60529 Degrees of protection provided by enclosures (IP Code)
Note: GB/T 4208-2017, Degrees of protection provided by enclosure (IP Code) (IEC 60529:2013, IDT)
IEC 61000-6-4 Electromagnetic compatibility (EMC) - Part 6-4: Generic standards - Emission standard for industrial environments
Note: GB 17799.4-2022, Electromagnetic compatibility (EMC) - Generic standards - Part 4: Emission for industrial environments (IEC 61000-6-4:2018, IDT)
IEC 61180 High-voltage test techniques for low-voltage equipment - Definitions, test and procedure requirements, test equipment
Note: GB/T 17627-2019, High-voltage test techniques for low-voltage equipment - Definitions, test and procedure requirements, test equipment (IEC 61180:2016, MOD)
IEC 62561-1 Lightning protection system components (LPSC) - Part 1: Requirements for connection components
Note: GB/T 33588.1-2020, Lightning protection system components (LPSC) - Part 1: Requirements for connection components (IEC 62561-1:2017, IDT)
IEC 62561-4 Lightning protection system components (LPSC) - Part 4: Requirements for conductor fasteners
Note: GB/T 33588.4-2020, Lightning protection system components (LPSC) - Part 4: Requirements for conductor fasteners (IEC 62561-4:2017, IDT)
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC: http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1.1
alarm
information indicating that a defined area is likely to be affected by thunderstorms and the accompanying lightning related events (LREs)
3.1.2
cloud-to-ground lightning; CG
electric discharge of atmospheric origin that is comprised of one or more cloud-to-ground lightning strokes that propagate from cloud to ground or vice versa and lead to a net transfer of charge between cloud and ground
3.1.3
coverage area; CA
area where a given warning equipment has a sufficient detection efficiency (DE) and/or accuracy to give a warning
3.1.4
detection efficiency; DE
percentage of lightning discharges that is detected by a sensor or a network
3.1.5
effective alarm; EA
alarm where a lightning related event (LRE) occurs in the surrounding area (SA) during the total alarm duration (TAD)
Note: An effective alarm can only be assessed when LREs are monitored. When LREs are not monitored the lightning related conditions (LRC) may define a valid alarm, see Figure 3 a).
3.1.6
effective alarm ratio; EAR
number of effective alarms (EAs) with respect to the total number of alarms (TNA)
3.1.7
time to clear; TTC
time between the occurrence of the last lightning related event (LRE) in the monitoring area (MA) and the time when the alarm is released
3.1.8
failure to warn; FTW
occurrence of a lightning related event (LRE) in the surrounding area (SA) for which no alarm occurred
3.1.9
failure to warn ratio; FTWR
number of failures to warn with respect to the total number of situations with lightning related events (LREs) affecting the surrounding area (SA)
3.1.10
false alarm; FA
alarm when there is no thunderstorm activity in the monitoring area (MA)
Example: An alarm due to TWS equipment malfunction or an alarm triggered by any signal not related to thunderstorm (snow, sand, electromagnetic disturbances, etc.).
3.1.11
false alarm ratio; FAR
number of false alarms with respect to the total number of alarms (TNA)
3.1.12
electrostatic field sensor; EFS
device for continuous monitoring of the atmospheric electrostatic field, where the sensor is located, associated with thunderstorms
Example: An electric field mill.
Note: Also known as atmospheric electric field meter, atmospheric field strength meter or electrostatic field sensor.
3.1.13
intra-cloud lightning; IC
electric discharge of atmospheric origin occurring within or among thunderclouds or between thunderclouds and air and which does not have a ground termination
3.1.14
lead time; LT
time between the start of an alarm and the effective occurrence of the first lightning related
event (LRE) in the surrounding area (SA)
Note 1: Any efficient preventive action should be completed before the end of the lead time.
Note 2: A lead time can only be assessed when LREs are monitored. When LREs are not monitored the lightning related conditions (LRC) may define an estimated lead time, see Figure 3 a).
3.1.15
lightning related event; LRE
event where one or more cloud-to-ground lightning (CG) occurs inside the surrounding area (SA)
3.1.16
lightning related conditions; LRC
static electric field that has reached a level high enough so that lightning is expected to occur at any time in the surrounding area (SA)
3.1.17
median location accuracy
median value of the distances between real stroke locations and the stroke location given by a lightning location system
3.1.18
monitoring area; MA
geographic area where the lightning or upcoming lightning (lightning is expected to occur at any time) activity is monitored in order to provide a valid warning for the surrounding area (SA)
Note: The monitoring area is smaller or equal to the coverage area.
3.1.19
preventive action
action of a temporary nature, that should be completed before the end of the lead time (LT), taken on the basis of the preventive information and included in the emergency plans
3.1.20
surrounding area; SA
geographic area in which a lightning related event (LRE) causes a potential danger and which surrounds and includes the target (TA) to be protected
Note: Any lightning related event (LRE) occurring in the surrounding area (SA) is potentially dangerous for the target (TA). This area is used when evaluating a thunderstorm warning system (TWS) to determine the performance parameters such as failure to warn ratio (FTWR).
3.1.21
target; TA
object or area for which a thunderstorm warning is needed
