This is a neat gadget that logs both temperature and relative humidity over days, months or even a year depending on the sample rate set.
It is simple to install and operate. With an USB port and driver software, temperature & humidity profile can be plotted on PC. This is one the gadget I really need.
Can't wait to check it out of course. A sample test plot shown below. It showed the dew point too.
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I have an additional tool to check against accuracy & correlation of humidity readings among my hygrostats.
Updated 17th Nov... Of course I can't wait to compare the accuracies of RH readings with my other instrument. The good news is the average difference between this data logger and my hand held meter is 2% over the 4hrs test duration. I am finally comfortable that my hygrostats control range can be set fairly accurately.