Siemens SENTRON Manual page 76

Appendix
Exposed conductive part (of electrical equipment)
Touchable, conductive component of an electrical device that is not normally live,
but which may be live in the event of a fault.
Electric shock
Pathophysiological effect caused by an electric current flowing through the body
of a person or animal.
Additional protection
Supplementary measure to reduce the risks that may arise to persons and livestock
if the basic and/or fault protection is rendered ineffective.
Basic protection
Protection against electric shock in a non-faulty system. Basic protection usually
corresponds to the protection against direct contact described in
DIN VDE 0100-410.
Fault protection
Protection against electric shock if a single fault occurs (e.g. faulty basic
insulation).
Fault protection usually corresponds to the protection against indirect contact
described in DIN VDE 0100-410.
Dangerous body current
Current flowing through the body of a person or animal with characteristics that
are likely to trigger a pathophysiological (harmful) effect.
Leakage current (in an installation)
Current flowing in a non-faulty circuit to ground or to an external conductive part.
Residual current
Sum of the instantaneous values of all currents flowing through all active
conductors in a circuit at a defined point in the electrical system.
In connection with residual current protective devices, the differential current
is referred to as "residual current" in accordance with the standards in the
DIN VDE 0664 (VDE 0664) series.
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