An electric arc is a discharge of electric current across a gap in a circuit. It is sustained by the presence of a thermally ionized column of gas (called a plasma) through which current flows.

An arc can be defined as an electric current flowing between two electrodes through an ionized column of gas. A charged anode and a charged cathode create an intense heat of the welding arc. The negative and positive ions are bounced between each other in the plasma column at an accelerated rate.

Overloaded circuits and faulty appliances or even wiring that is loose can result in an arcing issue. Damaged conductors within the circuit or overloaded circuits might cause crackling in the wires too.