A leakage current is an electric current flowing through a path which is not intended for conduction of current.
The leakage current , on the other hand, describes the sum of leakage currents and the current through internal capacities or interference suppression capacitors of devices with a protective conductor ( protection class I).
Leakage currents can occur when
- an insulator is not ideal, i.e. it has (low) electrical conductivity . In the case of capacitors , the leakage current is called “residual current”.
- the surface of an insulator has a leakage current , especially if there is contamination and / or moisture on the surface (see also tracking resistance ).
- inside of semiconductors spontaneously free charge carriers are formed, by an applied electric voltage migrate in the semiconductor crystal. This can e.g. B. caused or amplified by increased temperature or radiation .