IEC 60364-4-43:2023 provides requirements for:
- protection of live conductors, PEN conductors, PEM conductors, and PEL conductors against the harmful effects caused by overcurrent;
- coordination of measures for protection against overcurrent.
This fourth edition cancels and replaces the third edition published in 2008. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) the standard has been restructured, see Table 1 (Correspondence between IEC 60364‑4‑43:2008 and this document) below;
b) the measure "automatic disconnection of supply" has been designated as the preferred measure for protection against overcurrent;
c) all measures except the measure "automatic disconnection of supply" have been transferred into new normative annexes to indicate that these measures are usable in certain applications and under certain restricted conditions only (see Annex A, Annex B and Annex E);
d) a new clause "Terms and definitions" has been added;
e) new requirements have been added for the protection of the neutral or mid-point conductor (with and without triplen harmonics).