DIN EN 62305-4 Beiblatt 1
; VDE 0185-305-4 Beiblatt 1:2012-10
Protection against lightning - Part 4: Electrical and electronic systems within structures - Supplement 1: Sharing of the lightning current
Blitzschutz - Teil 4: Elektrische und elektronische Systeme in baulichen Anlagen - Beiblatt 1: Verteilung des Blitzstroms
Overview
This supplement to DIN EN 62305-4 (VDE 0185-395-4) describes, by means of basic examples, how various installation conditions can influence the sharing of lightning current in low-voltage installations and, as a consequence thereof, the lightning current load of the built-in SPDs. Compared to the information contained in Annex E of DIN EN 62305-1 (VDE 0185-305-1), further information about sharing of lightning current is provided, thus enabling planners for lightning protection systems to precisely determine, by application and combination of these basic examples, the actual sharing of lightning current even for more complex facilities. In addition to the explanations which of the lightning current parameters outlined in DIN EN 62305-1 (VDE 0185-305-1) shall be taken into account for the selection of SPDs, the supplement also offers users assistance for the selection and installation of a coordinated SPD protection in accordance with Annexes C and D of DIN EN 62305-4 (VDE 0185-305-4). The standard introduces both the various methods for identifying the sharing of lightning current in electrical systems, described in more detail in DIN EN 62305-1 (VDE 0185-305-1) and DIN EN 62305-4 (VDE 0185-305-4), as well as the decisive factors for the sharing of lightning current in energy systems, the influence of which on the current distribution and pulse shape of the lightning stroke currents is indicated on the basis of sample calculations. Situations such as: direct strike of lightning into structures (S1) and direct strike of lightning into installed lines (S3) according to DIN EN 62305-1 (VDE 0185-305-1) are taken into account. Furthermore, the sharing of lightning current in special structures is shown by means of selected examples. The committee responsible for this supplement to the European Standard is K 251 "Errichtung von Blitzschutzanlagen" ("Installation of lightning protection systems") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.