dew point range

dear all,

How to measure low RH % and from that how to calculate dew point temperature in C in the range -80 C to +30 C.
Which sensor is available for such low RH measurement and also please inform how to calculate moisture PPMV from RH and temperature.

Check - Arduino Playground - DHT11Lib

I have recoded some fortran code in C++ for Arduino,
please mention the reference implementation.

I believe that at -80°C the relative humidity is always going to be so low that you cannot practically measure it.

Measuring the Dew Point far below 0°C is difficult and expensive. If you really want to go done to -80°C (dew point temperature) I think your choices are a dew point mirror or low to sub ppm water sensor. I am not sure if there are other sensor as gas chromatographs and TDLS sensors that are capable to measure concentrations as low as that and both are very expansive.

thank u all for your most valuable reply.if i can able to make anything i will contact u as soon as possible. :slight_smile:

how to calculate dew point temperature in C in the range -80 C to +30 C.

Is google broken in your country ?