What is Partial discharge?
[[File:Partial discharge.svg|thumb|Partial discharge]] A '''partial discharge''' ('''PD''') is an [[electric discharge]] that breaks through a small portion of the [[Insulator (electricity)|insulation]] between two [[Electrical conductor|conductors]]. A discharge is when [[electrical charge]] that has accumulated is suddenly released (like a [[wikt:spark|spark]]). A partial discharge does not completely cross the insulation between the two conductors, only a small portion of it in one area. It may happen under the [[Stress (mechanics)|stress]] of [[high voltage]]. It is caused by a small opening (void) inside the insulating material. The insulating material can be either solid or fluid. The charge passing through this insulation is called [[electrical breakdown]]. {{science-stub}} [[Category:Electricity]]