This is helpful! Although I hope they do post more data. You can see these
are old professors since they post screen images of the computer data
instead of the output from the instruments converted directly into a graph.
This report says the probe used with the RH meter is an HP474AC. See:
Relative humidity and temperature probes using SICRAM module
HP474AC Pt100 5…98%RH -40°C…+150°C
If Horace Heffner is correct, these readings will be meaningless. I cannot
help thinking that the professor who did this probably knew what he was
doing; the instrument manufacturer probably made an RH meter that produces a
useful result at the rated temperature (up to 150°C); and the "
engineeringtoolbox.com" site I referenced is probably right.
Maybe there are different definitions of wet and dry steam percentages.
Anyway, why would they make an RH meter that serves no useful purpose at the
rated temperature? Why would anyone measure the RH and temperature except to
determine how wet the steam is?
(The meter probe in question measures RH and temperature.)