IEC 62793-2020 pdf download.Thunderstorm warning systems – Protection against lightning (IEC 62793:2020).
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 ] 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 62561 -4, Lightning protection system components (LPSC) – Part 4: Requirements for conductor fasteners
IEC 62561 -1 , Lightning protection system components (LPSC) – Part 1: Requirements for connection components
IEC 60068-2-75:201 4, Environmental testing – Part 2-75: Tests – Test Eh: Hammer tests
IEC 60529, Degrees of protection provided by enclosures (IP Code)
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 Electropedia: available at 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 1 to entry: 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).IEC 62793 pdf download.