Performance test of wisense temperature tags at extreme low conditions. Sensor ventilated using an ePTFE vent on the enclosure. Channel updating every minute.
Temperature and relative humidity in the ESCA labor of MTA ATOMKI, Debrecen, Hardware: WR703N (OpenWRT) + PL2303 + MSP430G2452 + DH22 sensor
Here are voltages from a series bank of three parallel trios of 400F, 2.7V supercapacitors regulated by an MSP430 to balance and stay under 7.3V. They are charged from a 5.2W, 9V solar panel.