IEC 61439-5:2023

Overview - IEC 61439-5:2023 (PENDAs)

IEC 61439-5:2023 is the part of the IEC 61439 series that defines specific requirements for public electricity network distribution assemblies (PENDAs) used in low‑voltage power distribution in public networks. It applies to stationary, enclosed assemblies used to distribute electrical energy in three‑phase systems up to 1 000 V AC (and DC systems up to 1 500 V DC). The third edition (2023) replaces the 2014 edition and includes a corrigendum; it is a technical revision that updates test and design requirements for PENDAs used indoors (substations) and outdoors.

Key topics and technical requirements

• Scope and definitions: Clarifies PENDA types - PENDA-I (indoor) and PENDA-O (outdoor). Open types are excluded. Assemblies are intended for installation and maintenance by skilled persons, though some outdoor types may be accessible to ordinary persons.
• Service conditions and constructional requirements: Specifies environmental, mechanical and material considerations for enclosures and internal structures to suit substation and outdoor installations.
• Electrical and dielectric tests: Includes performance verification and additional dielectric tests where PENDAs are used in substations with separate HV and LV earths.
• Mechanical testing and verification: Design verification and routine tests for mechanical strength, impact resistance and resistance to static/torsional loads. Notably, the 2023 edition omits the former requirement for mechanical tests at −25 °C for metallic enclosures.
• Thermal and loading considerations: Guidance on temperature rise verification and assumed loading factors - newly expanded to cover generation supplies and electric vehicle charging applications.
• Design verification & representative samples: Clarifies which sample assemblies and configurations are representative for verification testing.
• Documentation and information: Requirements for information exchange between manufacturer and DSO or end user, including items subject to agreement.

Practical applications and users

Who uses IEC 61439-5:

• Distribution system operators (DSOs) specifying LV distribution panels in transformer substations
• Switchgear and assembly manufacturers designing low‑voltage switchgear for public networks
• Electrical engineers and system integrators implementing public power distribution, including EV charging and distributed generation interconnections
• Test laboratories and certification bodies performing design, dielectric and mechanical verifications
• Spec writers, procurement teams and regulators defining network equipment requirements

Typical applications:

• LV distribution cubicles in public network substations
• Outdoor enclosed distribution cabinets for feeders and customer connections
• Panels integrating monitoring, control and signalling for smart‑grid deployments

Related standards

• IEC 61439-1 (General rules) - normative companion
• IEC 60695-11-10, IEC 62262, ISO 9223, ISO 6506-1 - cited normative references

Keywords: IEC 61439-5, PENDA, low‑voltage switchgear, public networks, PENDA-O, PENDA-I, power distribution, dielectric tests, design verification, EV charging.