What is Fault Current?
A fault current is an unintended, uncontrolled, high current flow through an electric power system. A fault current is caused by a very low impedance short circuit. This may be a short to ground or across phases. The resulting high current flow can result in overheating of equipment and conductors, excesses forces, and at times even serious arc flash, arc blast, and electrical explosion. The causes of a fault may include: lightning strikes, animals, dirt and debris, dropped tools, corrosion, and human error.
A fault current can degrade circuit breakers and other expensive electrical system components. By installing fault current limiters (FCLs), many companies can protect their power system from equipment failure with relatively little expense. Solid state FCL technology is available numerous industrial, commercial and institutional power system applications.