Irradiance sensor for measuring additional values The integration of sensors into a PV system allows the recording of additional measured values such as irradiance and ambient temperature, to name a few. This sensor is usually used to measure the temperature of surfaces. The module temperature can be measured by attaching the sensor to the back of the solar module. The temperature of the solar module plays a crucial role in determining the performance. Monitoring the temperature allows estimates of the nature of the output curve to be made.