SHORT-CIRCUIT CURRENTS IN THREE-PHASE AC SYSTEMS - PART 3: CURRENTS DURING TWO SEPARATE SIMULTANEOUS LINE-TO-EARTH SHORT CIRCUITS AND PARTIAL SHORT-CIRCUIT CURRENTS FLOWING THROUGH EARTH
International Electrotechnical Committee
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
6 Calculation of partial short-circuit currents flowing
through earth in case of an unbalanced short circuit
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
Annex A (informative) - Example for the calculation of two
separate simultaneous lineto-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
Describes 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. at nominal frequency 50 Hz or 60 Hz
| Document Type | Standard |
| Status | Current |
| Publisher | International Electrotechnical Committee |
| Committee | TC 73 |
