NTC and Humidity Sensors LOW COST

[gorkin]

hs12 humidity -ibm

Hello Brothers!
I need the NTC and Humidity Sensor for professional application (home system) in high shiped volumes...anyone have the devices for suggest-me?
Very thanks
Gorkin

 

[techie]

what vaue of NTC thermistors is needed. Also what is the type of humidity sensor required.

 

[Kripton2035]

I "love" the sensirion sht11 and family

https://www.sensirion.com

all digital, integrated humidity and temperature measurment, and very precise for the price compared to others solutions at the same price.

it costs 16 euros each, but I think you can get discount for a great quantity. I don't know what you mean by low cost !

 

[Trishool]

Great link

Great link kripton,

Hey try this also www.humirel.com . I wanna ask what type of sensor is best for humidity sensing ie Capacitive , CMOSense etc


Rgds
Ts

 

[gorkin]

NTC and Umidity sensor Request

Hi all!
My application is control for refrigeration and need the temperature sensor (two - one for enviroment inside and other for enviroment outside) and umidity sensor(for measurement of the air relatyve umidity).
I look for a very large amounts of manufacturer but prices are very expensives...
The small price for the temperature sensor is LM60 by U$0.24 ok but umidity sensor is very hight!!!
Anyone help-me?
Thanks

 

[Kripton2035]

with the sensirion sht11, you have the temp AND the humidity sensor in the same package...

the sht11 is sold by farnell at 13 euros for 100+ qty
on the sensirion web site, they say you can contact them for higher qty. may be you can reach 10 euros for 1000+ qty ?
by the way, if you look at others humid sensors, you may get cheaper ones, but you will have a lot of components to build around to make it works. with the sht11, you need a small microcontroler only.

 

[techie]

The cheapest way to make humidity measurement is the use the resistive sensors like HS12, HS15 etc. But they are logarithmic and require temperature compenstation. These can be built with cheap components but the design is quite complex and require a lot of expertise.
The SHT11 is a beautiful device that gives a clean digital data of both T and C. And compared to other sensors, the cost is not too high.
Remember that humidity measurement is no cheap measurement.

 

[Kripton2035]

actually the cheapest way to measure humidity is to use a small piece of wood, and measure resistance between the two sides. this will change with ambiant humidity, and is quite stable. if you don't need high precision, this could be your solution.

 

[ASIC]

Kripton2035. Thanks for an interesting suggestion. I love this kind of solution. I'll give you a handful of points.


ASIC

 

[gorkin]

NTC

Hi Kripton! Your idea it´s bettifull and great!!!
Simple and elegant. I will make this "sensor" and report the result for others members oportunatelly...

8O
gorkin

 

[Kripton2035]

thanks, but it's not my idea: it's been posted by marie65 in this topic : **broken link removed**

there is an interesting pdf file explaining the relation between resistance and humidity of wood
take a look there !

 

[mastorrage]

sensor

Try the resitive humidity sensor from Sencera, type H25K5, its below 1 Euro in volume.

/Mast

 

[techie]

If you can counter the logarithmic nature and temp coefficent of the resistor, then resistive sensors (as mentioned in above post for < 1Euro) is the way to go.

 

[mastorrage]

humidity

Temperture compensation should not be a problem since it will also be measured.

/mast