## 3 Results and Discussion  
### Pilot Project of Infrared Thermographic PV Analysis  
According to IEC TS 62446-3 Photovoltaic (PV) systems--Requirements for testing, documentation and maintenance--Part 3: Photovoltaic modules and plants--outdoor infrared thermography use with an IR camera with a resolution of \(\geq\)320 \(\times\) 240 pixels and a separate photo camera are recommended [10]. It is recommended to use cameras that have been calibrated within the previous two years. To conduct thermographic analyses, we used two infrared thermographic cameras, Flir E60 bx and Flir E6. Both cameras were IP 54 and had an operating time of up to 4 h. The camera differences are listed in Table 2.  
The significant differences in the cameras (for analysis purposes), in addition to the resolutions, are the optical characteristics of the field of view (FOV) and the instantaneous field of view (IFOV). Figure 5 illustrates the minimum distances of the cameras from the module to fit the complete module, described by Table 2, taken at an angle of 90\({}^{\circ}\). From this, we can conclude that the Flir E6 camera is not suitable for the analysis due to its lower resolution; however, in combination with the aforementioned IFOV optics, it can be used as a control and for additional analyses when the analysis object cannot be viewed from a greater distance. From the aspect of documenting the visual image, none of the cameras met the requirement of 9 Mpix visual image resolution. Therefore, photo documentation, for the purposes of visual analysis, was carried out using the cameras. Since the cameras have not been calibrated for more than two years, the analysis was \begin{table}
\begin{tabular}{c c c} \hline \hline
**Model** & **GSPV M6-340** & **JAM60S10-345/MR** \\ \hline Cell number & 72 (6 \(\times\) 12) & 120 (6 \(\times\) 20) \\ Maximum static load, front side (ex. snow, wind) & 5400 Pa & 5400 Pa \\ Maximum static load, back side (ex. wind) & 2400 Pa & 2400 Pa \\ Glass & 3.2 mm tempered glass & n/a \\ Encapsulant type & Ethylene vinyl acetate & n/a \\ Nominal output power 1 & 340 Wp & 345 Wp \\ Cell efficiency 1 & 19.83\% & 20.5 \% \\ Open-circuit voltage 1 & 46.49 V & 41.76 V \\ MPP voltage 1 & 37.8 V & 34.99 V \\ Short-circuit current 1 & 9.53 A & 10.54 A \\ MPP current 1 & 8.99 A & 9.86 A \\ Current temperature coefficient & +0.06\%/K & +0.044\%/K \\ Voltage temperature coefficient & \(-\)0.32\%/K & \(-\)0.272\%/K \\ Power temperature coefficient & \(-\)0.45\%/K & \(-\)0.354\%/K \\ Dimensions & 1956 \(\times\) 992 \(\times\) 40 mm & 1689 \(\times\) 996 \(\times\) 35 mm \\ \hline \end{tabular} 1  
\end{table} 
Table 1: Technical characteristics of the original 340 Wp monocrystalline silicon PV modules. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Camera** & **Flir E60 bx** & **Flir E6** \\ \hline IR resolution & 320 \(\times\) 240 pixels & 160 \(\times\) 120 pixels \\ Thermal sensitivity/NETD & \textless{}0.045 \({}^{\circ}\)C @ +30 \({}^{\circ}\)C/ 45 mK & \textless{}0.06 \({}^{\circ}\)C/\textless{}60 mK \\ Field of view (FOV) & 25\({}^{\circ}\)\(\times\) 19\({}^{\circ}\) & 45\({}^{\circ}\)\(\times\) 34\({}^{\circ}\) \\ Minimum focus distance & 0.4 m & 0.5 m \\ Spatial resolution (IFOV) & 1.36 mrad & 5.2 mrad \\ Spectral range & 7.5-13 \(\upmu\)m & 7.5-13 \(\upmu\)m \\ Object temperature range & \textless{}20 \({}^{\circ}\)C to +120 \({}^{\circ}\)C & \textless{}20 \({}^{\circ}\)C to +250 \({}^{\circ}\)C \\ Accuracy & \(\pm\)2 \({}^{\circ}\)C or \(\pm\)2\% of reading, for ambient & \(\pm\)2 \({}^{\circ}\)C or \(\pm\)2\% of reading, for ambient \\  & temperature 10 \({}^{\circ}\)C to 35 \({}^{\circ}\)C & temperature 10 \({}^{\circ}\)C to 35 \({}^{\circ}\)C \\  & 3.1 Mpixel (2048 \(\times\) 1536), & 0.3 Mpix (640 \(\times\) 480) \\ Built-in digital camera & FOV 53\({}^{\circ}\)\(\times\) 41\({}^{\circ}\) & FOV 55\({}^{\circ}\)\(\times\) 43\({}^{\circ}\) \\ \hline \end{tabular}
\end{table} 
Table 2: Comparison of FLIR E60 bx and E6 specifications.