THERMOGRAPHIC IMAGES UNDER LOAD

The heat given off by a solar generator can be captured with a thermographic camera. Temperature fluctutions insides a PV module are in many cases a sign of a problem or defect.

Defects discovered with thermographic imaging vary greatly. They include defects in electrical components like bypass diodes and junction boxes as well as mechanical flaws like delamination or cell breakage. Thermography also helps locate issues with soldering points, which can eventually cause problems in the long term.

Thermographic cameras take infrared images like a digital camera takes visible images. Essentially, the camera transates wavelengths from the infrared specturm into visible wavelengths: as color. Each color is defined so that it reflects a certain temperature.   Download as PDF document

Measurement process

When taking thermographic images, the module is fed with current, which causes the module and/or cells to warm up. This heating also occurs during normal operation when installed as part of a solar generator – that is when producing electricity from solar irradiation. The module temperature is then captured with a thermographic camera, which has a camera resolution of 1.23 megapixels (1,280 x 960 pixels). The resulting thermographic image can be used to detect damaged areas in the solar cells that do not produce current due to defects, which then heat up due to current from the active cell sections. This can damage the cells or even destroy an entire module.  

Defects and their documentation

Thermography makes it possible to reveal electical, installation, and processing errors and defects. It provides quick and simple information over a solar module’s true quality and any potential future risks. Since thermographic images are generally accepted by manufacturers and wholesalers as proof of a defect, this service can help resolve guarantee claims quickly.
 

Defects that can be detected with thermographic imagins include:

• A solar cell short circuit
• Inactive cell sections
• Humidity
• Faulty soldering
• Defective strings or bypass diodes  

Who can take advantage of this offer?

• First of all, a thermographic imaging service is of interest for vendors and installers that want to ensure the quality of received modules as part of their delivery control.
• Naturally, this service is also aimed at system operators that want to get a sense of module quality prior to installation, whether due to general curiosity or suspicion of a concrete defect.
• It is ideal for insurance companies that find it difficult in many cases to directly assess the extent of damage to an insured system.
• Research institutes and manufacturers can always request this service.

Do you have questions about this service? – Just give us a call!