IEC 61439 Standard Guide

IEC 61439 Standard Guide

Title: Low‑voltage switchgear and controlgear assemblies (LV switchboards/panels)IEC Websto... Replaces: old IEC 60439 series Voltage scope: ≤ 1 000 V AC; ≤ 1 500 V DC

Core rule: Part 1 (general rules) shall always be used together with the corresponding product‑specific part (‑2 /‑3 /‑4 /‑5 /‑6 /‑7). Part 1 alone cannot prove complianceIEC Websto....

Series Structure (Latest Editions)ABB Group

表格

Standard Full Title Application
IEC TR 61439‑0 Guidance to specifying assemblies Technical report, specification guide
IEC 61439‑1:2020 General rules Common definitions, service conditions, construction, verification, marking, documentation
IEC 61439‑2:2020 Power switchgear and controlgear assemblies (PSC) Industrial main switchboards, MCC, power control panels, solar‑LV cabinets
IEC 61439‑3:2024 Distribution boards for ordinary persons (DBO) Household / commercial consumer‑operated distribution boxes
IEC 61439‑4 Assemblies for construction sites (ACS) Temporary site distribution boxes
IEC 61439‑5:2023 Assemblies for public distribution networks (PENDA) Utility public‑network LV panels, substation LV boards
IEC 61439‑6 Busbar trunking systems (busways) Busbar systems
IEC 61439‑7 Assemblies for specific applications Marinas, campsites, market squares, EV charging station assemblies

Key Definitions & Technical Characteristics (‑1)ANSI Webst...

  1. Assembly: Complete combination of switchgear, control‑devices, busbars, wiring, enclosures.
  2. Main rated parameters:
    • \(I_n\): Rated current
    • \(I_{ng}\): Group rated current
    • \(I_{cw}\): Rated short‑time withstand current
    • \(I_{pk}\): Rated peak withstand current
    • \(I_{cc}\): Rated conditional short‑circuit current
    • RDF ‑ Rated Diversity Factor: Critical for temperature‑rise assessment for multi‑outgoing‑circuit panels
  3. Service conditions: ambient temperature, altitude, pollution degree, humidity.

Verification (13‑points design verification)

IEC 61439 abolished the old TTA / PTTA concept from IEC 60439. Instead, 13 design‑verification characteristics:

  1. Temperature rise
  2. Dielectric properties
  3. Short‑circuit withstand
  4. Protection against electric shock
  5. Clearances & creepage distances
  6. Mechanical operation
  7. Mechanical strength of enclosure
  8. Degree of protection (IP)
  9. Wiring / connections
  10. Components installation
  11. Internal electrical circuits
  12. Marking
  13. Electromagnetic compatibility (EMC)

✅ Verification methods: actual test, calculation, comparison with verified reference design.

Important: modification of assembly may require re‑verification.

Manufacturer Obligations

  • Define assembly ratings & parameters
  • Complete design‑verification evidence file
  • Marking on panel: manufacturer, serial‑no, part‑number, IEC‑61439‑X reference, main ratings, IP‑code
  • Supply documentation: installation, operation & maintenance manual, single‑line diagram, ratings summaryANSI Webst...

Practical Tips for Export / LV‑Panel Business

  1. EU market: EN IEC 61439 (CENELEC adoption of IEC text) is the harmonized standard for CE‑marking of LV assemblies.
  2. For solar‑project LV cabinets: normally falls under IEC 61439‑2.
  3. EV‑charging‑station‑related assemblies: IEC 61439‑7 + IEC 61851‑1.
  4. Cannot only test individual components; the whole assembly must fulfil 61439 requirements.

Short Comparison: IEC 60439 vs IEC 61439

表格

Item IEC 60439 IEC 61439
Compliance model TTA / PTTA 13‑point design verification
General rules Mixed in each part Centralised in Part‑1
Reference‑design method Limited Formalised for verification