Why voltage measurements?
All modules have the same consistant voltage curve over the day. Deviations of this specific value are clear indications of failures. Identifying the same characteristics enables precise error detection - and identification. In this curve you can see the voltage of two modules (orange and black lines) during one day in comparison, which are clearly similar. You can see as well how the temperature (blue line) on that day influenced the voltage: the warmer the modules, the lower the voltage.
Why temperature measurements?
Module temperatures vary within a plant by 15° Celsius due to different cooling. Temperature has a significant effect on the performance of a module: 15° Celsius reflects a power difference by 6%. How do you know if your system works fine if it can vary within specification by that number? Well - by measuring the temperature of each module and taking this into account of our plant performance calculations! Including module temperature measurements enables us to determine a precise PR - even for shortest periods.