UNE-EN IEC 61439-3:2026

Clause 1 of IEC 61439-1:2020 is applicable except as follows.

Replacement:

This part of IEC 61439 defines the specific requirements for distribution boards intended to be operated by ordinary persons (abbreviated DBO throughout this document see 3.1.101) as follows:

assemblies intended to be operated by ordinary persons (e.g. switching operations and replacing fuse-links), e.g. in domestic (household) applications;

assemblies containing outgoing circuits with protective devices intended to be operated by ordinary persons, complying e.g. with IEC 60898-1, IEC 61008, IEC 61009, IEC 62606, IEC 62423 and IEC 60269-3;

assemblies for applications where the nominal voltage to earth does not exceed 300 V AC (see table G.1 of Annex G of IEC 61439-1 :2020);

assemblies with a rated current (Inc) of the outgoing circuits not exceeding 125 A and the rated current (InA) not exceeding 250 A;

assemblies intended for use in connection with the generation, transmission, distribution and conversion of electrical energy, and for the control of equipment consuming electrical energy and for associated data processing;

enclosed, stationary assemblies;

assemblies for indoor or outdoor use.

DBOs can contain only: protection devices, control / signalling devices, or a combination of devices .e.g. circuit-breakers, WI/Fi router, load shedding relay, energy management, communication devices, lighting control.

This standard does not apply to an empty enclosure nor to individual devices and self-contained components, such as circuit-breakers, fuse switches, electronic equipment, etc. which comply with the relevant product standards, it describes the integration of devices and / or self-contained components into a DBO or into an empty enclosure forming a DBO.

This standard applies to DBOs designed, manufactured and verified on a one-off basis or fully standardised and manufactured in quantity.

DBOs may be assembled outside the factory of the original manufacturer. DBOs may be assembled by the original manufacturer or by an assembly manufacturer.

This standard does not apply to the specific types of assemblies covered by other parts of IEC 61439.

NOTE Enclosures for electrical accessories for household and similar fixed electrical installations are covered in IEC 60670-24