This tool is designed to determine the magnitude of electrical current that could flow during a short circuit at a specific point in an electrical system. It requires input data such as transformer size and impedance, conductor size and length, and utility fault current contribution. The output is expressed in amperes and represents the maximum current that protective devices must be able to interrupt.
Knowledge of this calculated value is crucial for electrical safety and code compliance. It allows engineers and electricians to select appropriately rated circuit breakers, fuses, and other protective equipment. Underestimating this current could lead to equipment failure, arc flash hazards, and potential injuries or fatalities. Historically, reliance on simplified estimations has led to inadequacies in protective device selection, highlighting the need for precise computation.