Master short circuit current calculations with step-by-step fault analysis, X/R ratio determination, asymmetrical current formulas, and circuit breaker rating selection. Complete guide with IEC 60909 and ANSI standards. Get %Z from nameplate or Table 1. Transformer impedance is determined as follows: The transf rmer secondary is short circuited. Factor depending on the saturation inductance of a generator. Once this value is known, safe intelligent protection of personnel and equipment can be accomplished. This booklet is not intended to replace more sophisticated methods such as system. This calculator implements industry-standard methods for short circuit current calculation based on IEEE 141/242 and IEC 60909 standards. The IEC 60909 standard provides a comprehensive method for calculating. Short circuits cannot always be preventedso system designers can only to try mitigate their potentially damaging effects.
[PDF Version]