The Hygrosens TEMOD-I2C-R1 is a digital converter board to read data from a PT1000 temperature sensor. It is the standard fast temperature sensor for the SUMO.
The board does have a 5V I2C interface. It can not be directly interfaced to 3.3V I2C interfaces as the Paparazzi boards have. A level shifting adapter board is needed. The PT1000 sensor is not included. The Heraeus M222 sensor can be used as it has a small mass.
Level shifter: Sparkfun
PT1000 sensor: Conrad
To use the humidity sensor:
<modules> <load name="temp_temod.xml"/> </modules>
The location of the sensor on the aircraft does matter. There are various papers that analyze the best location. So far we have installed them within tubes (to protect from sunlight/heating) on the wings. That might not be the optimum place. The precise -R1 sensor only operates down to -32°C.