For five years some of the Worlds’ top lightning experts reviewed measured lightning parameters, analyzed the data and, in 2013, published the results of their work in the 118 page Cigré (Council on Large Electric Systems) Technical Bulletin (TB) 549. Parameters for positive and negative lightning strokes, continuing current and flashes are thoroughly covered during this session.
TB 549 effectively states that the measured lightning parameters on which 10/350 test waveshape were based are insecure. At the time TB 549 was published, a new Website called ten350 appeared with the express purpose of burying the 10/350, offering as an alternative burst 8/20 impulse testing. The ten350 results for Chinese burst 8/20 testing of several manufacturers surge protective devices (SPDs) are discussed. A rocket triggered lightning paper, referenced in the ten350 site, included the question - why did a 40 kA SPD fail at lightning currents no greater than 1.6 kA? An explanation of the result will be presented.
The following will also be discussed: