Short Circuit Calculation

Introduction

Some of the related terms defined by the IEC's Electropedia:

Figure 1. 110 kV power line short-circuit

Figure 2. Short-Circuit Arc

• Short-Circuit: accidental or intentional conductive path between two or more conductive parts forcing the electric potential differences between these conductive parts to be equal to or close to zero.
• Short-Circuit Current: an over-current resulting from a short circuit due to a fault or an incorrect connection in an electric circuit.
• Short-Circuit Operation: no-load operation with zero output voltage (Note – Zero output voltage can be obtained when the output terminals are short-circuited).

• Line-to-Earth Short-Circuit: short-circuit between a line conductor and the Earth, in a solidly earthed neutral system or in an impedance earthed neutral system (Note – The short-circuit can be established, for example, through an earthing conductor and an earth electrode).

• Line-to-Line Short-Circuit: short-circuit between two or more line conductors, combined or not with a line-to-earth short-circuit at the same place

• Short-Circuit Current Capability: the permissible value of the short-circuit current in a given network component for a specified duration.

AC Short-Circuit Analysis

IEC 60909 AC Short Circuit Analysis

DC Short-Circuit Analysis

IEC 61660 DC Short Circuit Analysis

ANSI/IEEE 946 DC Short Circuit Analysis