IEC 61439-2:2020

Overview

IEC 61439-2:2020 is the International Electrotechnical Commission standard that specifies specific requirements for power switchgear and controlgear assemblies (PSC-assemblies). This third edition (2020) updates the 2011 version and applies to assemblies with rated voltages up to 1 000 V AC or 1 500 V DC, nominal frequencies up to 1 000 Hz, and for indoor or outdoor, stationary or movable installations. The standard covers assemblies used in generation, transmission, distribution and conversion of electrical energy, equipment control and associated data processing - including dedicated provisions for photovoltaic assemblies (PVA).

Key topics and requirements

• Scope & applicability: PSC-assemblies for power distribution and control; excludes standalone devices (circuit-breakers, UPS, converters) which are covered by product standards.
• Constructional requirements: mechanical and electrical construction rules, forms of internal separation, enclosure integrity and protection.
• Forms of internal separation: clarified requirements; when separation form is higher than 1, all parts remaining live in a functional unit compartment when switched off must be protected to at least IPXXB.
• Performance and verification: detailed design verification and routine verification procedures (electrical, thermal, dielectric, mechanical).
• Temperature‑rise verification: new requirements for assemblies with natural cooling and circuits >1 600 A (by reference design + calculation) and for assemblies with active cooling up to 1 600 A.
• IP and active cooling: consideration of ingress protection when assemblies use active cooling systems.
• Photovoltaic assemblies (PVA): Annexes DD, EE, FF provide PVA-specific definitions, service conditions and design verifications.
• Information & interfaces: requirements for documentation, user‑manufacturer agreements (see Annex AA / EE).

Practical applications and who uses it

IEC 61439-2 is essential for professionals who design, manufacture, test or specify low-voltage power switchgear and controlgear assemblies:

• Manufacturers - to design and verify PSC-assemblies to international requirements.
• Design engineers & system integrators - to ensure compliant integration of switchgear into power distribution, machine control and PV systems.
• Test laboratories and certification bodies - for type and routine verification procedures.
• Utilities, EPC contractors and large industrial users - when specifying assemblies for distribution, generation, conversion and renewables (solar PV).
• Machine builders - as supplementary requirements when assembling electrical equipment for machinery (references IEC 60204-1).

Related standards

• IEC 61439-1:2020 (general rules) - to be read together with Part 2.
• IEC 60204-1:2016 - electrical equipment of machines (supplementary).
• IEC 60947 series - product standards for switchgear components.
• IEC 60092-302-2 - supplementary requirements for shipboard assemblies (as applicable).
• IEC 60664-1 - insulation coordination at high frequencies.

This standard helps ensure safety, reliability and interoperability of low-voltage power switchgear and controlgear assemblies across industrial, utility and renewable energy applications.