ShortCkt is designed to calculates the three-phase short-circuit currents. It is based on ANSI/IEEE Std 141 and 242. The intent of this program is to provide a means for determining the numerical value of the symmetrical short-circuit rms current. The application returns with the maximum symmetrical short-circuit current available ½ cycle after the short circuit starts. The program considers the power company system, generators, synchronous motor and induction motors as basic sources of fault current. Transformers and cables are taken into consideration for total impedance calculations. Calculations of fault current are usually made to ensure that the interrupting capacities of the equipment are adequate to handle the currents available at their locations.