HD 581 S1:1991
(Main)Application guide for calculation of short-circuit currents in low-voltage radial systems
Application guide for calculation of short-circuit currents in low-voltage radial systems
This application guide presents a practical method to be used when calculating short-circuit currents in low-voltage networks. The method corresponds strictly with HD 533 and leads to conservative results with sufficient accuracy. Two short-circuit currents which differ in magnitude are to be calculated: -the maximum short-circuit current which causes the maximum thermal and electromagnetic effects on electrical equipment and determines the required capacity or rating; -the minimum short-circuit current which may be a basis for the adjustment of protective devices.
Berechnung von Kurzschlußströmen in unvermaschten Drehstrom-Niederspannungsstrahlennetzen; Anwendungsleitfaden
Guide d'application pour le calcul des courants de court-circuit dans les réseaux à basse tension radiaux
Présente une méthode pratique de calcul des courants de court-circuit dans les réseaux à basse tension. Cette méthode correspond rigoureusement à la HD 533 et conduit à des résultats prudents et suffisamment précis. Deux courants de court-circuit, qui diffèrent en amplitude, sont à considérer: - le courant de court-circuit maximal qui provoque les plus grands effets thermiques et électromagnétiques sur le matériel électrique et détermine ses caractéristiques; - le courant de court-circuit minimal qui peut servir de base au réglage des dispositifs de protection.
Application guide for calculation of short-circuit currents in low voltage radial systems (IEC 60781:1989)
General Information
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