IEC 61558-2-3:2023

Overview - IEC 61558-2-3:2023 (Ignition Transformer Safety)

IEC 61558-2-3:2023 is the International Electrotechnical Commission standard that defines particular safety requirements and tests for ignition transformers for gas and oil burners. This third edition (2023) replaces the 2010 edition and is a technical revision that aligns structure and references with IEC 61558-1:2017. It is published as a group safety publication (IEC Guide 104) and includes the 2023 corrigendum.

Key scope points:

• Applies to fixed single‑phase, air‑cooled (natural or forced), dry‑type ignition transformers used in gas and oil burner ignition systems.
• Covers transformers with encapsulated or non‑encapsulated windings, including those that incorporate electronic circuits.
• Rated supply voltage ≤ 1 000 V AC, rated/operational frequency ≤ 500 Hz.
• Rated short‑circuit output current ≤ 500 mA AC; no‑load or rated output voltage ≤ 15 000 V AC.
• Intended to be used together with IEC 61558-1:2017; where conflicts with IEC 61558-2-16 (switch mode power supplies) occur, the more stringent requirement applies.

Key technical topics and requirements

This part supplements IEC 61558-1 by addressing ignition‑transformer‑specific aspects such as:

• Protection against electric shock and required insulation systems
• No‑load and loaded output voltage/current limits and tests
• Short‑circuit and overload protection and test procedures
• Heating and temperature rise limits under normal and fault conditions
• Insulation resistance, dielectric strength and leakage current testing
• Mechanical strength, marking, terminal and wiring requirements
• Creepage distances, clearances and tracking resistance for high‑voltage output
• Ingress protection, resistance to rusting, and other constructional requirements

(The standard’s table of contents lists specific clauses and test methods for these topics.)

Practical applications and who uses this standard

IEC 61558-2-3 is used by:

• Transformer manufacturers and designers developing ignition transformers for gas or oil burner systems.
• OEMs of burners, boilers, HVAC and industrial heating systems specifying compliant ignition components.
• Compliance and certification bodies performing type testing and safety assessment.
• Test laboratories implementing the specified electrical, thermal and mechanical tests.
• Procurement and quality teams writing specifications to ensure product safety and regulatory conformity.

Practical uses include designing products to meet electrical safety limits, creating test plans for type approval, writing procurement specifications, and ensuring safe integration of ignition transformers into burner assemblies.

Related standards and notes

• Must be used in conjunction with IEC 61558-1:2017 (general requirements).
• For switch‑mode power supply units used in ignition systems, IEC 61558-2-16 also applies - the stricter requirement governs.
• The edition adjusts structure and references for harmonization and includes corrigendum updates.

Keywords: IEC 61558-2-3, ignition transformers, gas burners, oil burners, transformer safety standard, IEC 61558-1, electrical safety, no‑load output voltage, short‑circuit output current, air‑cooled transformers, electronic ignition circuits.