Solmetric PVA-1000S, User Manual

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6 Measuring Irradiance, Temperature, and Tilt
6-11
Using SmartTemp to Measure Cell Temperature
The SmartTemp method uses a blend of the From I-V and backside thermocouple
methods, taking best advantage each while avoiding the biggest limitations of each. The
blend changes as a function of irradiance:
•
At irradiance values lower than 400W/m2, temperature is obtained from the
backside thermocouple.
•
At irradiance values greater than 800W/m2, temperature is calculated using the
From I-V method.
•
At irradiance values between 400 and 800W/m2, the PVA software
progressively shifts between the thermocouple and From I-V methods.
This strategy employs the From I-V method at high irradiance values where it is most
accurate, and relies on the backside thermocouple at low irradiance values where there is
a relatively small temperature offset between module backside and cell.
If the software detects a temperature difference of more than 5C between the
thermocouple and From I-V methods, it switches to to use just the thermocouple. This
reduces the likelihood of temperature errors caused by a missing module or shorted
bypass diode.