> > MOISTURE > > > > > 10-90% Humidity Sensor BC1333-ND $11.94 > > www.digikey.com > > > > Hey, that sounds like just the ticket! A cheap, > > small sensor > > that can detect "humidity"! Never used one > before, > > but there > > it is, waiting to be played with. > > I am not a PhD and this topic is a bit far from my > "core know-how". Nevertheless, by coincidence, I > spent > those 2 last weeks playing with RH and thermocouples > for technologic validation in a pharma application. > Those people are very stringent about instruments, > calibration, methodologies, tracking and so on. My > little experince with RH sensor lead me to be very > very reluctant to trust the above sensor. I checked > briefly the data sheet and I would just use it at > home, nothing more. I recently bought several RH > probe > from 200$ to 700$. Even at those prices, accuracy > guaranteed is only 2% RH. I even required special > calibration (not standard factory calibration) > according to known calibration protocol but found > deviation when using probes on-field. Drift has to > be > checked frequently. All this in an extremly clean > and > controled environment, with controled flow, not in > waxed, propolised and turbulent flow environment. > Quality RH probe seem to me quite big and invasive > in > the hive. But once again, I am not an expert in this > field and I may ignore adapted instruments. > > Even for thermocouples, I would check closely raw > data, type of thermocouples used, drift, calibration > and so on before being confident with data although > the 8 or 16 bits data logger will give you 5 or > maybe > 10 numbers after the point. Especially in a study > spread on several years in such environment as a > hive. > For example, 0.4C offset drift is not uncommon, even > with a T-type thermocouple. And I do not speak about > "electronic noise", shielded wire, and data logger > sampling... Shortly, everyone can put a button > temperature sensor in the hive and obtain results. > But > validated results obtained according to the > state-of-the-art allowing flow interpretation is > someting else. Forget cheap and quick > (unfortunately)! > > > > Hervé > > > > > > > Yahoo! Mail : votre e-mail personnel et gratuit qui > vous suit partout ! > Créez votre Yahoo! Mail sur > http://fr.benefits.yahoo.com/ > Yahoo! Mail : votre e-mail personnel et gratuit qui vous suit partout ! Créez votre Yahoo! Mail sur http://fr.benefits.yahoo.com/ :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: -- Visit www.honeybeeworld.com/BEE-L for rules, FAQ and other info --- ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::