This part of IEC 61439 contains the specific requirements and tests for assemblies for construction sites (ACS) suitable for use on construction and similar sites. IEC 61439-4 cancels and replaces the previously valid IEC 60439-4 and defines the specific requirements for assemblies for constructions sites as follows: - assemblies for which the rated voltage does not exceed 1 000 V in case of a.c. or 1 500 V in case of d.c.; - assemblies where the nominal primary voltage and the nominal secondary voltage of transformers incorporated in ACS are within the limits specified above; - assemblies intended for use on construction sites, both indoors and outdoors, that is temporary places of work to which the public do not generally have access and where building construction, installation, repairs, alteration or demolition of property (buildings) or civil engineering (public works) or excavation or any other similar operations are carried out; - transportable (semi-fixed) or mobile assemblies with enclosure. The significant changes are the alignment to edition 2 of IEC 61439-1, as applicable. Technical modifications have not been made. The responsible committee is DKE/UK 431.1 "Niederspannungs-Schaltgerätekombinationen" ("Low-voltage switchgear and controlgear assemblies") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.