How to qualify and use local storm detectors for risk assessment ?
Résumé
Lightning detection techniques becomes very popular. The risk evaluation standard IEC 62305- 2 published late 2006 will probably push forward that use. As a matter of fact, this risk evaluation technique means that you should provide protection measures until you decrease the calculated risk below a certain tolerable level. But in some cases, the risk is too high and standard lightning protection techniques cannot reduce it enough. This is particularly the case for large buildings with high risks, building with explosive atmosphere or place in the world where keraunic level is very high. What to do in such case? Basically, one of the only remaining option is to reduce the risk duration. This means to implement lightning detection measures such as local storm detector. If the storm detector is providing a signal early, it is possible to evacuate people from a dangerous zone, to stop a dangerous process or even to disconnect from the network and operate on independent power generators. You need then to characterize the device to know what it its efficiency. You need to be sure that a) the device will warn you enough in advance b) that the warning is reliable (no false warning) and c) that the warning will occur in any circumstances. It is then needed to establish testing procedures to evaluate the key parameters for the storm detection devices. Basically parameters a) and b) are important for the operation of the device and parameter c) is the one needed in the risk evaluation. Purpose of this paper is to present how these devices may be tested and how the results may be used in the risk assessment procedure