Every year electrical systems are destroyed, even though surge arresters were built in to protect them. Why? Because lightning is not what it seems … People have been researching this phenomenon of nature for hundreds of years and to date no one has been able to explain all of the details of its generation. However, since Benjamin Franklin’s first attempt – i.e., with a kite on a wire cable – several discoveries have been made. We know that a bolt of lightning can only occur between clouds. We also know the fact that upward and downward lightning bolts, that have different polarities, exist. It is much less well known that a flash of lightning can consist of many electrical impulses that are discharged within a very short time. As early as the 1960s, an oscillograph was used to measure more than six impulses within one lightning flash. This measurement was an early record of our problem today. When a bolt of lightning strikes in the immediate vicinity of an electrical system, it commonly leads to the destruction of the surge protector because the immense amount of energy in this short time completely overloads the arrester. These are based on the current standard (IEC 61643-11), which in fact requires that several electrical pulse currents should be able to flow through the device under test, however, the pulses are spaced several minutes apart. That is exactly where the problem lies. A lightning event, in which several pulses flow through the lightning bolt down into the earth, is, as a general rule, shorter than one second. As a result of this discovery, people tried to develop effective protection from the multiple pulses of a lightning strike for quite some time. This gap in both personal and system protection has been closed with the Multi-Pulse product from Jan Bilin GmbH. Our Multi-Pulse is the first surge protective device in the world that can safely dissipate multiple lightning currents.
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