IEC 62477-2:2018

Overview

IEC 62477-2:2018 is an international standard published by the International Electrotechnical Commission (IEC) that defines safety requirements for power electronic converter systems (PECS) and equipment operating within high voltage ranges. Specifically, it covers converters with rated system voltages starting from 1 000 V AC or 1 500 V DC up to 36 kV AC or 54 kV DC. This standard applies to electronic power conversion and switching components, including their control, protection, monitoring, and measurement functions.

As a group safety publication aligned with IEC Guide 104, IEC 62477-2:2018 provides a common terminology and establishes minimum safety requirements for PECS used in various applications, including renewable energy sources such as solar, wind, tidal, wave, and fuel cells. It also serves as a reference for product committees in developing standards for adjustable speed electric power drives (PDS), standalone uninterruptible power supplies (UPS), and stabilized DC power supplies.

Key Topics

• Hazard Protection: The standard specifies methods to reduce risks related to electric shock, fire, thermal, mechanical, and energy hazards during normal operation and maintenance.
• Fault and Abnormal Conditions: Requirements include short-circuit and overload protection, with guidelines on input short-circuit withstand strength and backup protection coordination.
• Electrical Safety Measures: Details on insulation, basic and fault protection, enhanced protective measures, and compatibility with residual current-operated devices (RCD).
• Enclosure and Wiring Requirements: Defines requirements for enclosures, cable routing, color coding, and accessible connections to ensure safe installation and operation.
• Testing Protocols: Comprehensive test procedures for visual inspections, mechanical robustness, electrical performance, fault simulations, material and environmental tests, and hydrostatic pressure.
• Marking and Information: Specifies labeling requirements, commissioning instructions, information for safe use, and maintenance guidelines including capacitor discharge warnings and multi-source supply precautions.
• Arc Fault Rating Labeling: Establishes arc fault rating labels alongside testing instructions to enhance safety awareness and compliance.
• Scope Exclusions: Clarifies that telecommunications apparatus (except power supplies), functional safety under IEC 61508, railway and electric vehicle equipment, and highly customized converter systems following installation standards like IEC 61936-1 are not covered.

Applications

IEC 62477-2:2018 is essential for manufacturers, designers, and engineers involved with:

• High-voltage power electronic converters used in renewable energy technologies (solar, wind, tidal, wave power).
• Development and certification of adjustable speed drives, ensuring safe power conversion in industrial motor control.
• Standalone UPS systems that require high voltage power electronic components with verified safety protocols.
• Design and production of stabilized DC power supplies operating at high voltages.
• Reference for product committees tasked with creating standards for power electronic systems in medium- to high-voltage ranges.
• Safety conformity assessments in line with international regulations, helping reduce hazards such as electric shock and fire in industrial and utility-scale installations.

Related Standards

• IEC Guide 104 - Provides guidance for group safety publications related to PECS and their integration into product standards.
• IEC 61508 - Covers functional safety, complementing IEC 62477-2’s focus on electrical and mechanical safety requirements.
• IEC 61936-1 - Standard for power installations exceeding 1 kV AC, relevant for custom-designed PECS applications not covered by IEC 62477-2.
• IEC 62477-1 - Part 1 of this series, detailing general safety requirements for power electronic converter systems and equipment below the voltage ranges specified in Part 2.

By adhering to IEC 62477-2:2018, industry professionals ensure their power electronic converter systems meet stringent international safety standards, minimizing risks across high-voltage applications in energy conversion and industrial processes. This enhances operational reliability, protects personnel, and facilitates regulatory compliance worldwide.