Overview
IEC TR 61000-1-9:2024 is a Technical Report from the IEC that addresses electromagnetic compatibility (EMC) measurement uncertainty for harmonic current emissions. It provides practical formulae, worked examples and spreadsheet files to evaluate measurement uncertainty for tests performed under IEC 61000-3-2 and IEC 61000-3-12, using the ISO/IEC Guide 98-3 (GUM) approach. The report is aimed at helping testing laboratories and conformity assessors apply uncertainty analysis to conformity decisions.
Key topics and technical requirements
- Scope and methodology: Applies the GUM (ISO/IEC Guide 98-3) method to harmonic emission tests and describes a measurement model (including single-phase measurement circuits).
- Uncertainty components: Detailed treatment of major contributors, including:
- current measurement equipment performance,
- input impedance of current measurement devices,
- test voltage RMS value and its harmonic distortion,
- loading effect of voltmeters,
- method-related effects and worst‑case scenarios.
- Worst‑case and typical examples: Tables and annexes present worst‑case uncertainty budgets for different equipment classes and selected harmonics (e.g., Class A, C, D, various harmonic numbers).
- Formulas and spreadsheets: Practical formulae link each uncertainty source to its contribution; accompanying spreadsheets facilitate hands‑on calculations in line with GUM.
- Conformity decisions: Guidance on how measurement uncertainty supports pass/fail decisions for harmonic current limits, compatible with ISO/IEC 17025 and JCGM 106 practices.
Practical applications and users
Who benefits:
- Accredited testing laboratories (ISO/IEC 17025) performing EMC harmonic tests.
- Conformity assessment bodies and certification schemes evaluating compliance with harmonic limits.
- EMC engineers and product manufacturers who need to quantify uncertainty when demonstrating compliance with IEC 61000-3-2 / IEC 61000-3-12 limits.
- Metrology and quality managers implementing GUM-based uncertainty budgets for power-harmonics testing.
How it is used:
- Prepare measurement uncertainty budgets for harmonic emission tests.
- Inform conformity decisions by combining measured values with calculated expanded uncertainties.
- Reduce unnecessary failures by distinguishing true non‑compliance from measurement uncertainty.
Related standards
- IEC 61000-3-2 (harmonic limits for equipment ≤16 A)
- IEC 61000-3-12 (harmonic limits for 16 A–75 A)
- IEC 61000-4-7 (harmonics measurement instrumentation)
- ISO/IEC Guide 98-3 (GUM)
- ISO/IEC 17025 (laboratory competence)
- JCGM 106 / ISO/IEC Guide 115 (conformity assessment guidance)
Keywords: IEC TR 61000-1-9:2024, EMC, measurement uncertainty, harmonic current emissions, IEC 61000-3-2, IEC 61000-3-12, GUM, ISO/IEC 17025, conformity assessment.
Open preview (PDF)Electromagnetic compatibility (EMC) - Part 1-9: General - Evaluation of uncertainty for the measurement of harmonic current emissions
