Determining available short circuit current or MVA values is one of the most important aspects of designing power distribution systems. Short circuits and their effects must be considered in selecting electrical equipment, circuit protection devices, carrying out arc flash analysis. The short circuit on-line calculator presented on this web-site is offered in effort to satisfy the need for a convenient, comprehensive method of calculating three phase distribution system short circuit currents. The calculator allows the designer to quickly obtain the maximum potential short circuit MVA and current at each nod (bus) in a radial electric power distribution system.

Opposite to popular single line short circuit procedures, the proposed calculator process both one- and multibranch- three phase power distribution systems. Delta connected loads can be processed upon delta to wye conversion.

Many programs and procedures of this type do not properly account for motor loads as they simply