Over Current Fault:
Any current in excess of the rated current of equipment or the capacity of a conductor. It may result from overload, short-circuit, or ground-fault.
An over current fault can be divided into two:
- Short circuit &
An abnormal connection (including an arc) of relatively low impedance, whether made accidentally or intentionally, between two points of different potential.
Operation of equipment in excess of normal, full-load rating or of a conductor in excess of rated ampacity that, when it persists for a sufficient length of time, would cause damage or dangerous overheating.
Effect of Over current:
In both cases (short circuit as well as over current), the cables overheat and, if there are no adequate protections, the anomalous temperature rise damages the electrical plant and the connected equipment, with the risk of causing fires and then serious damages to people and things.