IEC 61204-3:2016

Overview

IEC 61204-3:2016 - Low‑voltage switch mode power supplies - Part 3: Electromagnetic compatibility (EMC) - specifies EMC requirements for switch mode power supply (SMPS) units supplied by source voltages up to 1 000 V AC or 1 500 V DC, providing AC and/or DC outputs. The standard excludes inverter outputs that establish AC mains. This third edition updates scope, normative references and aligns emission and immunity limits with current IEC/CENELEC guidance.

Key topics and requirements

• Scope & applicability
  • Applies to SMPS (low‑voltage) including AC/DC and DC/DC topologies (except full inverters for mains generation).
  • Clarifies equipment types, configurations and exclusions (see clause 1.1.x).
• Emission requirements
  • Low‑frequency phenomena (commutation notches, current harmonics, flicker).
  • High‑frequency conducted emissions for input and DC output ports.
  • High‑frequency radiated emissions and disturbance power measurement (measurement methods defined).
  • Emission limits updated to align with latest normative references (Annex H contains emission limits).
• Immunity requirements
  • Performance criteria and test levels for different environments: residential, commercial/light industrial and industrial.
  • Immunity tests cover high‑frequency disturbances, enclosure ports, signal/control ports, DC/AC input and output ports (see Tables 2–9).
• Test conditions and reporting
  • Standard defines general test conditions, classification of ports, statistical aspects, safety considerations and required test report contents.
• Special considerations
  • Guidance for DC/DC converters, power supply families and disturbance power measurement methods (informative and normative annexes).

Practical applications - who uses this standard

• SMPS manufacturers - design to meet EMC limits, select filters, shielding and grounding strategies.
• EMC test labs - implement measurement procedures for conducted and radiated emissions and immunity verification.
• Product compliance engineers - prepare compliance dossiers and test reports for certification and market access.
• System integrators and OEMs - ensure power supplies meet EMC requirements for target environments (residential vs industrial).
• Regulatory and certification bodies - evaluate conformity to IEC EMC requirements for low‑voltage power supplies.

Benefits and SEO keywords

Using IEC 61204-3:2016 helps reduce interference, improve product reliability and achieve compliance for low‑voltage switch mode power supplies, EMC compliance, conducted emission, radiated emission, immunity testing, harmonics, and flicker. The standard is essential for anyone designing, testing or certifying SMPS for commercial or industrial markets.

Related standards

• Normative references are updated in this edition - consult the standard’s Normative references clause for linked CISPR/IEC EMC standards and guides (CENELEC Guide 24, IEC Guide 107) to ensure full compliance.

Note: Always obtain and use the latest official IEC publication and applicable corrigenda when applying IEC 61204-3:2016 in product development or testing.