Re: humidity sensor

On Tue, 24 Mar 2009 18:25:24 -0400, Wes wrote:

Is there a reasonable priced humidity sensor that interfaces with pic's
easily? Phanderson has a board but I think at 43 USD, it is out of my
price range. I have some one wire temp chips on the way.

My application is to drive a cooling fan to bring in cool air into my
garage (shop) at night and exhaust air when the inside is hotter than
the outside.

Since I have machine tools inside, dew point is important in the
calculation. I don't want to bring in moisture laden air if my tools
are below dew point.

Thanks,

Wes

Trying to figure out dew point from temperature and humidity can be a
thankless task -- the vapor pressure of water varies exponentially with
temperature, so anything more than a few degrees difference and you're
almost out of luck.

There are dewpoint sensors out there. It may even be fun to build one.

--
http://www.wescottdesign.com
.

Relevant Pages

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  • humidity sensor
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    (sci.electronics.basics)