EL analysis

Electroluminescence analysis (EL analysis) is the process of photographing a photovoltaic system in the dark with a camera equipped with an LWP high-pass filter to detect the weak emission caused by the passage of reverse current through the cells of a photovoltaic module.

By analysing an EL Outdoor image, it is possible to identify:

1. defective (or short-circuited) by-pass diodes inside the module junction box
2. micro-fractures of the cells
3. PID (Potential Induced Degradation) of the cells
4. frontal electrical contact problems affecting the cells
5. mismatch of cells and/or modules present on the system

Electroluminescence analysis is especially recommended in the following cases:

• following hail
• underperforming system
• problems resulting from poor insulation
• suspected presence of PID
• quality verification of pre-installation on new modules

Electroluminescence analysis can be carried out at any time of year, although it is mainly recommended to perform it at night.