FOREWORD
1 Scope and object
2 Normative references
3 Terms and definitions
4 Symbols
5 Calculation of currents during two separate simultaneous
line-to-earth short circuits
5.1 Initial symmetrical short-circuit current
5.1.1 Determination of M[(1)] and M[(2)]
5.1.2 Simple cases of two separate simultaneous
line-to-earth short circuits
5.2 Peak short-circuit current, symmetrical short circuit
breaking current and steady-state short-circuit
current
5.3 Distribution of the currents during two separate
simultaneous line-to-earth short circuits
6 Calculation of partial short-circuit currents flowing
through earth in case of an unbalanced short circuit
6.1 General
6.2 Line-to-earth short circuit inside a station
6.3 Line-to-earth short circuit outside a station
6.4 Line-to-earth short circuit in the vicinity of a station
6.4.1 Earth potential U[Etn] at the tower n outside
station B
6.4.2 Earth potential of station B during a line-to
earth short circuit at the tower n
7 Reduction factor for overhead lines with earth wires
8 Calculation of current distribution and reduction factor
in case of cables with metallic sheath or shield
earthed at both ends
8.1 Overview
8.2 Three-core cable
8.2.1 Line-to-earth short circuit in station B
8.2.2 Line-to-earth short circuit on the cable between
station A and station B
8.3 Three single-core cables
8.3.1 Line-to-earth short circuit in station B
8.3.2 Line-to-earth short circuit on the cable between
station A and station B
Annex A (informative) Example for the calculation of two
separate simultaneous line-to-earth short-circuit
currents
Annex B (informative) Examples for the calculation of
partial short-circuit currents through earth
Annex C (informative) Example for the calculation of the
reduction factor r[1] and the current distribution
through earth in case of a three-core cable
Annex D (informative) Example for the calculation of the
reduction factor r[3] and the current distribution
through earth in case of three single-core cables