What is fault current?

Fault current, also known as short circuit current, is the maximum current that flows through a system during a fault condition. A fault condition occurs when there is a sudden and unexpected short circuit or ground fault in the electrical system, causing a large increase in current flow.

Fault current is a critical parameter in the design and operation of electrical systems, as it can cause damage to equipment, create safety hazards, and disrupt the normal operation of the system. Proper protection measures, such as circuit breakers and protective relays, are used to detect and interrupt fault currents to prevent damage to the system and ensure the safety of personnel.

Fault current is typically measured in amperes and is calculated based on the system's voltage, impedance, and the type of fault that occurs. It is important for engineers and electricians to accurately determine the fault current levels in a system in order to properly size protective devices and ensure the overall reliability of the electrical system.