Need for Circuit Protection

Current flow in a conductor always generates heat. The greater the current flow, the hotter the conductor. Excess heat is damaging to electrical components. High levels of heat cause the insulation to breakdown and flake off, exposing conductors. For that reason, conductors have a rated continuous current carrying capacity or ampacity. Excessive current is referred to as overcurrent. An overcurrent may result from an overload, short circuit, or ground fault. Thus we need an protection system.

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