The storm cloud
Possibly reaching several kilometres height and depth, Lightning is produced by cumulo-nimbus storm clouds.
A separation of charges in the cloud is caused by atmospheric turbulences and big differences of temperature (up to – 60 °C at 10 km altitude) : the upper part of the cloud is made up of positively charged ice crystals and the base contains negatively charged water droplets.The base of the cloud influences locally the charge of the ground at the surface, attracting (...) read more
Without any appropriate protection, the lightning current propagation can produce several effects. That is the reason why it is necessary to arrange protection according to basic rules, paying attention especially to the earthing systems and to their interconnections with the conductive elements, and to the down conductors and electrical equipment in the installation.
The ionization of the air produced by the lightning current provokes numerous luminous particles, (...) read more
The increasingly frequent presence of sensitive electronics makes electrical equipment additionally vulnerable to transient overvoltages associated with lightning.
Compared to other possible origins (industrial overvoltages, network overvoltages, electrostatic discharges, …), the transient overvoltages from the atmospheric origins are the most dangerous for the equipment and for the electrical or electronic installations. Caused by enormous energies generated in a very short time, it can (...) read more