Home News Reviews Forums Shop


Designing a humidity meter.

General discussion. Come introduce yourself. Talk about whataver you want!

Designing a humidity meter.

Postby pranav81 on Tue Aug 03, 2004 9:41 am

Hello guys.My professor has assigned me a electronics project.I have been told to build a humidity measurement circuit.I found a dew sensor circuit,but the prof. says that is not the one.
According to the prof. the circuit should display the humidity of the atmosphere on LCD/LED display.
I have searched on the internet in vain.

Could you guys help me build this circuit?

Thanks in advance.


::Pranav::
Last edited by pranav81 on Tue Aug 03, 2004 1:37 pm, edited 1 time in total.
Increasingly mathematics will demand the courage to face its implications.
User avatar
pranav81
CD-RW Player
 
Posts: 1160
Joined: Thu Dec 05, 2002 6:57 am
Location: Solapur,Maharashtra,India

Postby JamieW on Tue Aug 03, 2004 1:11 pm

Just use a fat man and a white board. He writes down how much he is sweating.
A man has been charged after allegedly punching a 73-year-old woman in the face, breaking her nose and stabbing her in the arm with a corkscrew before hitting a second woman with a bottle at a wedding reception in the Whitsunday Islands.
User avatar
JamieW
Chicken Farmer
 
Posts: 634
Joined: Sun Aug 19, 2001 8:00 pm

Postby pranav81 on Tue Aug 03, 2004 1:29 pm

LOL.

Thanks a lot for the suggestion,JamieW.I will try to tell that to my professor.

Any other suggestions guys?


::Pranav::
Increasingly mathematics will demand the courage to face its implications.
User avatar
pranav81
CD-RW Player
 
Posts: 1160
Joined: Thu Dec 05, 2002 6:57 am
Location: Solapur,Maharashtra,India

Postby Phoenix '97 on Tue Aug 03, 2004 7:09 pm

I believe I read somewhere that inexpensive humidity meters measure humidity by measuring the capacitance of some thin film, I'm not sure what it's made of.
Assuming pressure is a constant, if you know the temperature and humidity, you can determine omega (grams of water per kilogram of dry air), dewpoint, and several other properties. So if you get your circuit working to the point where it reads dewpoint or one of those other properties, it's only a matter of calculation to determine the relative humidity.
Phoenix '97
CD-RW Player
 
Posts: 213
Joined: Tue Jul 23, 2002 4:11 am
Location: Winterpeg

Postby MonteLDS on Tue Aug 03, 2004 11:44 pm

at 1st i thought it said Hummilty
User avatar
MonteLDS
CD-RW Player
 
Posts: 989
Joined: Fri Nov 08, 2002 2:32 pm
Location: San Fran Bay Area CALIFORNIA

Postby JamieW on Wed Aug 04, 2004 12:02 am

Because you often think that real words are actually words that don't exist?
A man has been charged after allegedly punching a 73-year-old woman in the face, breaking her nose and stabbing her in the arm with a corkscrew before hitting a second woman with a bottle at a wedding reception in the Whitsunday Islands.
User avatar
JamieW
Chicken Farmer
 
Posts: 634
Joined: Sun Aug 19, 2001 8:00 pm

Postby pranav81 on Wed Aug 04, 2004 8:26 am

Dear Phoenix '97,
Hi.You are right about measuring humidity that way.The sensor uses capacitance,all right.When humidity is more the capacitance across the sensor is less than when the air is drier.I wanted a circuit which will display the humidity using the sensor.
I would be glad if you post a circuit diagram which uses this capacitance sensor.

Waiting for reply.

::Pranav::
Increasingly mathematics will demand the courage to face its implications.
User avatar
pranav81
CD-RW Player
 
Posts: 1160
Joined: Thu Dec 05, 2002 6:57 am
Location: Solapur,Maharashtra,India

Postby ClayBuster on Wed Aug 04, 2004 10:57 am

http://www.smokeshopmag.com/0402/showcase/

Look at the Digital Hygrometer
Rick
User avatar
ClayBuster
CD-RW Player
 
Posts: 205
Joined: Sun Apr 11, 2004 1:11 pm
Location: MI.

Postby Phoenix '97 on Wed Aug 04, 2004 6:59 pm

I really wouldn't know how to start on something like that, I'm afraid, I was just recalling stuff I've learned in previous courses and stuff I remember reading.
Just this spring I finished my Electronics II course which dealt with op-amps, diodes, transistors, and transistor amplifiers. I'll be taking E III in the fall. :)
I also just recently finished a microprocessing systems course... if your project dealt with a 6800 or 68000 I might be able to write some assembly for that, too. :p
Phoenix '97
CD-RW Player
 
Posts: 213
Joined: Tue Jul 23, 2002 4:11 am
Location: Winterpeg

Postby pranav81 on Thu Aug 05, 2004 9:17 am

Thanks a lot Phoenix '97 for the info.I would be glad if you would help me search the circuit diagram for my project.

ClayBuster,I want to build a humidity meter.If I get a readymade one,my professor will kick me. :-?

Basically I have to get a circuit diagram approved by the professor,then he will ask us to get the components,then design the PCB,etc.


::Pranav::
Increasingly mathematics will demand the courage to face its implications.
User avatar
pranav81
CD-RW Player
 
Posts: 1160
Joined: Thu Dec 05, 2002 6:57 am
Location: Solapur,Maharashtra,India


Return to The Beer Garden

Who is online

Users browsing this forum: No registered users and 1 guest

All Content is Copyright (c) 2001-2017 CDRLabs Inc.