Overview
IEC TS 63140:2021 - Photovoltaic (PV) modules - Partial shade endurance testing for monolithically integrated products - defines accelerated test methods to quantify permanent power loss in monolithically integrated PV modules caused by partial shading. The Technical Specification provides three selectable tests that represent normal use, misuse, and most severe misuse conditions. It is applicable to modules made by monolithic integration (cells built on a common substrate/superstrate and scribed during fabrication) with one series-connected cell group or multiple series-connected groups connected in parallel. It is not applicable to modules assembled from separately interconnected cells.
Key topics and technical requirements
- Test objective: Excite non-uniform current flow and reverse bias in shaded cells to reveal permanent degradation (shunts, localized heating) and quantify consequent drop in power output.
- Three test types:
- Use (U) test: Check manufacturer documentation for specific warning text; if present, no physical test is required. If absent, proceed to the Misuse (M) test.
- Misuse (M) test: Simulates a person walking past the module in bright conditions using a human-sized mask that blocks about 90% of incident light; up to 1 m of the shadow can overlap the module height.
- Most Severe Misuse (SM) test: Simulates a narrow cleaning tool passing across the module, with a mask that blocks about 100% of incident light across the full module height.
- Test conditions: High-irradiance, repeated mask movement while the module operates under current flow (accelerated conditions intended to emulate extended outdoor stress).
- Apparatus & measurements:
- Stabilization per IEC 61215-2 MQT 19.
- I‑V curve measurement per IEC 61215-2 MQT 02 and IEC 60904‑1.
- Constant-current operation equipment able to sink/source up to 1.5× module nameplate I_mp (requirements depend on presence of bypass diodes).
- Limitations: These procedures are not equivalent to IEC 61215‑2 hot‑spot endurance testing and do not replace safety qualification standards.
Applications and who should use it
- PV module manufacturers: design verification and robustness assessment for monolithic modules against partial shading and misuse scenarios.
- Independent test laboratories & certification bodies: evaluate shade-induced degradation and provide evidence for product qualification or failure analysis.
- Quality, reliability and warranty engineers: assess long-term performance risk from partial shading and inform warranty policies.
- System integrators and asset owners: understand how monolithic modules respond to common shading events and cleaning practices.
Related standards
- IEC 61215-2 (Design qualification and test procedures)
- IEC 61730-2 (PV module safety qualification)
- IEC 60904 series (I‑V measurement and solar simulator requirements)
- IEC TS 61836 / IEC TS 60904-13 (definitions, electroluminescence)
Keywords: IEC TS 63140, partial shade endurance testing, monolithically integrated PV modules, partial shading, PV module testing, misuse test, most severe misuse, shade-induced degradation.