I'm working with an electronic temperature logger that is being affected by heat generated internally.
How does one come up with a calibration equation to calculate a more accurate reading of ambient temperature based on what the temperature sensor reads, taking into account its own power consumption?
After a few hours and in equilibrium, the sensor reports values that are actually 1 degree Celsius higher than the ambient room temperature (22C) measured by a calibrated device. The sensor is accurate to 0.1 degree C at reporting the temperature of the device itself (which due to heat generated by the electronics has gotten warmer)
The device consumes ~0.1 watts of power, weighs about 200g and has an average specific heat capacity of 1.0 j/g (weighted mix of glass, abs, fr-4, copper). Dimensions are 1"x 3"x 4".
What I've got so far is this heating calculation: 200g * 1c * 1.0j/g / 0.1w / 60s = ~33 minutes to heat up 1 degree.
I'm assuming what we need is to figure out Sensor value - Heat-generated + Heat-dissipated to arrive at actual temperature. Which will require measure the K in newton's law? then what?
I'd really appreciate you help here.