IEC 62548-1:2023

Overview

IEC 62548-1:2023 establishes essential design requirements for photovoltaic (PV) arrays, with a strong focus on safety and reliability in solar power system installations. Developed by the International Electrotechnical Commission (IEC), this standard covers the full spectrum of DC-array wiring, electrical protection devices, switching, and earthing provisions for PV systems. While it includes the PV array and final power conversion equipment (PCE), it does not extend to energy storage devices, loads, or the AC/DC distribution network supplying loads.

This standard directly addresses electrical and mechanical risks specific to PV systems, such as sustained electrical arcs and unique fault conditions, equipping designers and installers with guidelines to maximize system reliability and safety.

Key Updates in IEC 62548-1:2023

• Enhanced requirements for PV systems featuring DC to DC conditioning units.
• Updated criteria for mounting structures and cable selection.
• Revised safety provisions regarding electric shock protection, insulation monitoring, and earth fault detection.
• New guidance for isolation means, including installations using bifacial modules or non-optimal orientations.
• Introduction of KI factor calculations, anti-PID (Potential Induced Degradation) protections, and arc flash considerations.

Key Topics

• Design Safety for PV Arrays: Defines robust safety measures tailored to the direct current (DC) nature of PV systems, including arc fault management and reinforced overcurrent protection.
• Electrical Protection and Isolation: Outlines requirements for fuses, circuit breakers, insulation monitoring, and earth fault detection to mitigate fire, arc, and shock risks.
• Component and Installation Requirements: Details selection criteria and installation practices for cables, connectors, combiner boxes, and switching devices to ensure system integrity.
• Mounting and Mechanical Considerations: Sets out structural and environmental requirements for PV array mounting, including specialized guidance for bifacial modules and non-optimal orientations.
• Earthing and Bonding: Provides clear directives for the earthing and bonding of exposed conductive parts and the use of equipotential bonding conductors.
• Labelling and Documentation: Specifies marking, identification, and documentation requirements to support safe operation and maintenance throughout the PV system lifecycle.
• Protection with Battery Connection: Adds requirements when PV arrays are directly connected to batteries at the DC level to avert backfeed and reverse current hazards.

Applications

IEC 62548-1:2023 is vital across the solar industry for ensuring the safe and effective deployment of PV arrays in a variety of applications, including:

• Residential and Commercial Rooftop PV Installations: Enhances safety through standardized wiring, isolation, and protection protocols.
• Utility-Scale and Ground-Mounted PV Power Plants: Provides design consistency and risk mitigation for large-scale projects, complementing IEC TS 62738 for facilities with restricted access.
• Specialized PV Installations: Informs the design of systems utilizing bifacial modules, tracking systems, or building-integrated photovoltaics (BIPV), requiring advanced mounting and configuration strategies.
• Battery-Integrated PV Systems: Offers crucial additional safeguards for arrays directly linked to energy storage at the DC level.

By adhering to IEC 62548-1, professionals can ensure PV arrays meet international safety requirements, facilitate inspection and certification, and protect both end-users and maintenance personnel from electrical or mechanical hazards.

Related Standards

To provide comprehensive PV array safety and performance, IEC 62548-1:2023 is intended for use in conjunction with related standards, such as:

• IEC 60364 Series: General requirements for low-voltage electrical installations.
• IEC 62109 Series: Safety requirements for power conversion equipment in PV systems.
• IEC 61215 & IEC 61730: Qualification and safety for PV modules.
• IEC 62446-1 & IEC 62446-2: Documentation, commissioning, and maintenance of PV systems.
• IEC TS 62738: Design guidelines for large ground-mounted PV plants.
• IEC 61643-31: Surge protection for photovoltaic installations.
• IEC 62930: Electric cables for PV systems.

Adoption of IEC 62548-1:2023 supports global harmonization of solar PV array design, fostering safer, more reliable systems and accelerating renewable energy integration worldwide.