IEC 61558-2-13:2009

Overview

IEC 61558-2-13:2009 is an international safety standard from the International Electrotechnical Commission (IEC) addressing the requirements and testing methods for auto transformers and power supply units incorporating auto transformers, rated for supply voltages up to 1,100 V. This standard covers both general-purpose auto transformers and those with incorporated electronic circuits, aiming to ensure electrical, thermal, and mechanical safety. The 2009 edition updates and replaces the previous 1999 version and aligns with the general requirements stated in IEC 61558-1:2005.

IEC 61558-2-13 establishes particular requirements to minimize the risks associated with design, construction, and use of auto transformers in diverse electrical installations. It also has the status of a group safety publication, guiding the implementation of safe practices for manufacturers, test laboratories, and regulatory bodies worldwide.

Key Topics

Key safety aspects and technical issues covered by IEC 61558-2-13:

• Scope: Applies to stationary or portable, single-phase or polyphase, air-cooled (natural or forced) dry-type auto transformers for supply voltages up to 1,100 V AC, and frequencies up to 500 Hz.
• Marking and Identification: Requirements for clear marking, including rated values and relevant graphical symbols indicating fail-safe, short-circuit proof, and non-short-circuit proof auto transformers.
• Electrical Characteristics: Specifies limits for rated output voltage, core power, and operational frequencies according to transformer type and application.
• Ensuring Safety: Addresses electrical safety (protection against electric shock), thermal and mechanical robustness, short-circuit and overload protection, insulation requirements, and tests for dielectric strength and leakage current.
• Construction Requirements: Includes guidelines on mechanical strength, protection against dust and moisture ingress, and specific rules for plug-connected auto transformers and polarity detection.
• Creepage and Clearance Distances: Sets requirements for insulation distances, with guidance for voltages above 1,000 V.
• Testing: Provides procedures for verifying compliance, including assessment of output voltage differences under load and no-load conditions, as well as performance under fault conditions.
• Compatibility: Designed to be used in conjunction with IEC 61558-1 for comprehensive coverage of transformer safety requirements.

Applications

IEC 61558-2-13:2009 is vital for multiple sectors where safe and reliable operation of auto transformers is critical:

• Manufacturing and Design: Helps transformer and power supply unit manufacturers meet international safety standards, enabling easier product certification and market access.
• Electrical Installations: Guides integrators and installers to select units compliant with the highest safety and performance criteria, reducing risk in commercial and industrial environments.
• Testing and Certification: Used by test laboratories and certification bodies to evaluate product compliance, ensuring products meet established benchmarks for global trade.
• Regulatory Compliance: Assists regulators and inspection agencies in verifying conformity to electrical safety legislation.

Practical examples of covered applications include control panels, industrial automation, building services, and any context where auto transformers are required without the need for circuit insulation.

Related Standards

Other IEC standards complementing IEC 61558-2-13:

• IEC 61558-1: General requirements and tests for safety of transformers, reactors, and power supply units.
• IEC 61558-2-16: Particular requirements for safety of switch mode power supply units and transformers, relevant when electronic circuits are integral to the power supply.
• IEC 60664-1: Insulation coordination for equipment within low-voltage systems, referenced for determining insulation requirements.

Using IEC 61558-2-13 in conjunction with these standards supports comprehensive product safety, quality assurance, and international acceptance for transformers and related power supply equipment.