73 - Short-circuit currents

IEC 60909-0:2016 is applicable to the calculation of short-circuit currents in low-voltage three-phase AC systems, and in high-voltage three-phase AC systems, operating at a nominal frequency of 50 Hz or 60 Hz. It establishes a general, practicable and concise procedure leading to results which are generally of acceptable accuracy and deals with the calculation of short-circuit currents in the case of balanced or unbalanced short circuits. This second edition cancels and replaces the first editi...view more

IEC TR 60865-2:2015(E) shows the application of procedures for the calculation of mechanical and thermal effects due to short circuits as presented in IEC 60865-1. Thus, this technical report is an addition to IEC 60865-1. It does not, however, change the basis for standardized procedures given in that publication. This second edition cancels and replaces the first edition published in 1994 and constitutes a technical revision. It includes the following changes. The determinations for auto reclo...view more

IEC 60865-1:2011 is applicable to the mechanical and thermal effects of short-circuit currents. It contains procedures for the calculation of: the electromagnetic effect on rigid conductors and flexible conductors, the thermal effect on bare conductors. For cables and insulated conductors, reference is made, for example, to IEC 60949 and IEC 60986. For the electromagnetic and thermal effects in d.c. auxiliary installations of power plants and substations reference is made to IEC 61660-2. Only a....view more

IEC 60909-3:2009 is also available as IEC Standards+ 60909-3:2009 which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 60909-3:2009 specifies procedures for calculation of the prospective short-circuit currents with an unbalanced short circuit in high-voltage three-phase a.c. systems operating at nominal frequency 50 Hz or 60 Hz, i. e.:
- currents during two separate simultaneous line-to-earth sh...view more

IEC 60909-2:2008(E) comprises data of electrical equipment collected from different countries to be used when necessary for the calculation of short-circuit currents in accordance with IEC 60909-0. It may be applied for calculating short-circuit currents in low-voltage networks if they are in accordance with typical equipment employed in the user's country. The collected data and their evaluation may be used for medium- or high-voltage planning purposes and also for comparison with data given by...view more

Describes method for calculating short-circuit currents in d.c. auxilliary systems in power plants and substations, which can be equipped with the following equipment, acting as short-circuit current sources: - rectifiers in three-phase a.c. bridge connection for 50 Hz; - stationary lead-acid batteries; - smoothing capacitors; - d.c. motors with independent excitation Provides a generally applicable method of calculation which produces results of sufficient accuracy on the conservative side. The...view more

Describes a method for calculation of the mechanical and thermal effects on rigid conductors caused by short-circuit currents in d.c. auxilliary installations in power plants and substations, as described in IEC 61660-1. Provides a method which has wide application and which gives results of sufficient accuracy. The calculation method is based on substitute functions, which cause approximately the same maximum stresses in the conductors and the same forces on the supports as the actual electroma...view more