IEC 60909-3:2003 Short-Circuit Currents in Three-Phase a.c. Systems - Part 3: Currents during two separate simultaneous line-to-earth short circuits and partial short circuit currents flowing through earth

Geneva, Switzerland: The International Electrotechnical Commission (IEC), 2003. — 72 p.IEC 60909-3:2003 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 short circuits in isolated neutral or resonant earthed neutral systems;
- partial short-circuit currents flowing through earth in case of single line-to-earth short circuit in solidly earthed or low-impedance earthed neutral systems.