Overview
IEC TR 63227:2020 provides guidance for lightning and surge voltage protection of photovoltaic (PV) power supply systems. It addresses protection measures against effects of lightning strikes and atmospheric surge voltages to maintain safety, functionality, and availability of PV installations. This Technical Report (IEC TC 82) describes design principles, protection concepts, and practical measures where lightning/surge protection is required.
Key topics and technical requirements
The report covers a comprehensive set of technical topics relevant to PV surge protection and lightning mitigation:
- Design principles and risk management: causes of damage (galvanic, magnetic and electric field coupling) and strategies to assess and reduce risk.
- Lightning Protection System (LPS): requirements for external (air-termination, down-conductors) and internal lightning protection, including the use of the lightning protection zone concept.
- Surge Protective Devices (SPDs): selection and coordination of SPDs (Class I and Class II tested types), including criteria for voltage-limiting and voltage-switching devices and combined configurations.
- Lightning equipotential bonding and functional earthing: measures to reduce potential differences between PV modules, racks, inverters and building earthing.
- Routing, shielding and cable management: cable routing, shielding and shielding by metal channels to reduce inductive coupling and induced voltages.
- Inspection and documentation: commissioning, inspection, and record-keeping for ongoing safety and maintainability.
- Practical examples and annexes: informative annexes provide examples for saddle roofs, free-field (ground‑mounted) systems, metal roofs/façades, and shadowing considerations.
Practical applications and who uses this standard
IEC TR 63227 is intended for professionals involved in design, installation and operation of PV systems, including:
- PV system designers and engineers
- Electrical installers and contractors
- Asset owners and operations & maintenance teams
- Safety and compliance officers, insurers and certifiers
- Project managers for rooftop and ground‑mounted PV projects
Use cases include defining SPD placement and class selection, designing earthing and equipotential bonding schemes, specifying external lightning protection, and documenting inspection/maintenance regimes.
Related standards
Key normative references cited in the document include:
- IEC 60364-4-44 (Protection for safety - voltage disturbances and electromagnetic disturbances)
- IEC 60364-7-712 (Requirements for solar PV installations)
- IEC 61643-11 (Low-voltage surge protective devices - requirements and test methods)
IEC TR 63227 should be used in conjunction with these standards when specifying lightning and surge protection for PV power supply systems.
Keywords: IEC TR 63227, lightning protection PV, surge protection photovoltaic, SPDs, lightning equipotential bonding, PV earthing, surge voltage protection standard.