Overview
IEC TS 63397:2022 - Photovoltaic (PV) modules: Qualifying guidelines for increased hail resistance - is a Technical Specification from the IEC that defines additional test requirements for PV modules intended for deployment in regions with elevated hail exposure. The document supplements the baseline IEC 61215 design-qualification tests by introducing a repeatable hail stress sequence and post-hail thermo‑mechanical testing to reveal internal damage (e.g., cell micro‑cracks) and resulting performance loss that conventional hail tests may not detect. The copy includes the July 2023 corrigendum.
Key topics and requirements
- Purpose: Provide a standardized method to assess and compare increased hail resistance of PV modules beyond IEC 61215 minimums.
- Pre-conditioning: Modules undergo 200 h damp heat to simulate humidity/heat exposure before hail stress.
- Hail test (HMQT 17): A refined hail-impact procedure derived from IEC 61215 MQT 17, intended to improve accuracy, repeatability and comparability of results.
- Post-hail stress sequence: Modules exposed to hail are then subjected to thermo‑mechanical stress tests (sequence C) - including cyclic (dynamic) mechanical load (MQT 20), thermal cycling (MQT 11) and humidity‑freeze (MQT 12) - to propagate hidden damage that may cause long‑term degradation.
- Performance assessment: Power loss at STC and low irradiance, insulation and wet leakage tests, and electroluminescence (EL) imaging are used to quantify damage and compare hail‑stressed modules against control/reference samples.
- Reporting: Detailed reporting of power loss, EL images before/after tests, and impact mapping is required. Annex A provides hail‑map examples to help relate test severity to geographic risk.
Applications and users
IEC TS 63397 is practical for:
- PV module manufacturers seeking to validate design improvements (glass, encapsulant, cell interconnects) for hail-prone markets.
- Independent test laboratories performing comparative hail-resistance qualification.
- Project developers, asset owners and insurers assessing module suitability and long‑term yield risk in regions with frequent/large hail.
- R&D teams optimizing cell interconnection or module mechanical design to limit crack propagation after impacts.
By revealing hidden vulnerability and enabling apples‑to‑apples comparisons, the TS supports more informed procurement, risk assessment and product development.
Related standards
- IEC 61215 series - PV module design qualification (baseline hail test referenced).
- IEC 61730 series - PV module safety requirements.
- IEC TS 63209-1 - Related mechanical stress test sequencing (test flow alignment).
- Hail maps and the Hail Register are referenced for geographic risk context.
Keywords: IEC TS 63397:2022, hail resistance, PV modules, hail test, electromagnetic luminescence, IEC 61215, module qualification, solar PV reliability, damp heat, thermal cycling.