scope:

This part of IEC 60364 provides requirements for the protection of live conductors from the effects of overcurrents.
This standard describes how live conductors are protected by one or more devices for the automatic disconnection of the supply in the event of overload (Clause 433) and short-circuit (Clause 434) except in cases where the overcurrent is limited in accordance with Clause 436 or where the conditions described in 433.3 (omission of devices for protection against overload) or 434.3 (omission of devices for protection against short-circuit) are met.
Coordination of overload protection and short-circuit protection is also covered (Clause 435).
NOTE 1 Live conductors protected against overload in accordance with Clause 433 are considered to be protected also against faults likely to cause overcurrents of a magnitude similar to overload currents.
NOTE 2 The requirements of this standard do not take account of external influences.
NOTE 3 Protection of conductors according to this standard does not necessarily protect the equipment connected to the conductors.
NOTE 4 Flexible cables connecting equipment by plugs and socket-outlet to fixed installations are not part of the scope of this standard and for this reason are not necessarily protected against overcurrent.
NOTE 5 Disconnection does not mean isolation in this standard.