LV installationsOfficial source linked
IEC 60364-5-52:2009 + AMD1:2024
Selection and erection of low-voltage wiring systems, including relevant installation and conductor considerations.
When it mattersWhen selecting cable installation methods, examining current ratings and assessing LV wiring design.
Scope noteThe IEC consolidated edition includes the 2024 amendment. National adoptions and project requirements can differ.
LV installationsOfficial source linked
IEC 60364-5-54:2011 + AMD1:2021
Earthing arrangements, protective conductors and protective bonding conductors.
When it mattersWhen designing protective earthing and bonding provisions for LV electrical installations.
Scope noteEarthing effectiveness depends on the whole system and applicable national installation rules.
Switchgear & assembliesOfficial source linked
IEC 61439-1:2020
General rules, construction requirements and verification for low-voltage switchgear and controlgear assemblies.
When it mattersWhen evaluating an LV panel assembly, temperature-rise verification, short-circuit withstand and assembly documentation.
Scope notePart 1 is used WITH the applicable assembly-specific part, commonly Part 2 for power switchgear assemblies; a busbar sizing calculation alone is not conformity verification.
TransformersOfficial source linked
IEC 60076-1:2011
General requirements, rating, marking and technical framework for power transformers.
When it mattersWhen interpreting transformer nameplate parameters and specifying transformer electrical characteristics.
Scope noteApply relevant additional parts of the IEC 60076 series for transformer type and tests.
TransformersOfficial source linked
IEC 60076-11:2018
Requirements applicable to dry-type power transformers within its defined scope.
When it mattersWhen evaluating cast-resin/dry-type MV/LV transformers and their type-specific requirements.
Scope noteUse the actual nameplate and manufacturer thermal/cooling data. Not every dry transformer has identical insulation or cooling.
MV cablesOfficial source linked
IEC 60502-2:2014 + AMD1:2024 (corrected 2026)
Construction, dimensions and testing requirements for extruded-insulation power cables rated 6–30 kV.
When it mattersWhen specifying and checking MV XLPE cable constructions, voltage class and cable tests.
Scope noteCable construction requirements are not a substitute for site-specific thermal ampacity calculations or screen earth-fault checks.
MV cablesOfficial source linked
IEC 60287-1-1:2023
Steady-state cable-current rating equations and loss calculations, including buried, ducted and air installations.
When it mattersWhen calculating installation-specific thermal ampacity with suitable material, cable and environmental parameters.
Scope noteRatings depend on cable construction, soil thermal resistivity, cable arrangement, surrounding conditions and losses.
System studiesOfficial source linked
IEC 60909-0:2026
Calculation of three-phase AC short-circuit currents in low- and high-voltage networks at 50/60 Hz.
When it mattersWhen determining prospective short-circuit duty for protection, conductors, transformers and switchgear.
Scope noteThe 2026 third edition supersedes IEC 60909-0:2016. Simplified transformer fault estimates are NOT full IEC 60909 calculations.
ProtectionOfficial source linked
IEEE C37.2-2022
Device-function numbers, acronyms and contact designations used in electrical power systems.
When it mattersWhen reading relay specifications, protection schematics, test sheets or switchgear documentation.
Scope noteSuffixes such as N, G or T may be manufacturer- and application-dependent; check the actual relay manual.