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HR202 humidity sensor value output

PostPosted: Wed Dec 09, 2015 12:50 pm
by azhamrosli
How to convert this value? example : i get 145 value...
I newbie for this..Hope can help me...Thank.
How to convert this value? example : i get 145 value...what it mean? is that is RH value..or voltage value. and how to convert to get RH in %. please help me.i'm try to use data table base on attachment https://docs.google.com/document/d/13uc ... FuYkc/edit and https://drive.google.com/file/d/0BzFWfM ... AtMHc/view but i not understand how to convert it.any example code can i refer to get RH%.


Note:
HR202 humidity sensor

Thank You.

Re: HR202 humidity sensor value output

PostPosted: Wed Dec 09, 2015 4:38 pm
by ZaM
hi, i dont know how u get 145 from. but i assume u read from analog pin. i think u using 5v system and supply the sensor with 5v vcc. my opinion: if the sensor only can read 20-95%, then the value should be 20% equal to 0, 95% equal to 1023. if we consider no loss, linear equation should be like this ((value from sensor/1023)x(95%-20%))+20%=actual RH value. but it just my opinion. maybe you can plot the graph using real HUMIDITY meter to compare the accuracy. Note that temperature will affect the resistance too. . :D :mrgreen:

Re: HR202 humidity sensor value output

PostPosted: Thu Dec 10, 2015 10:00 am
by azhamrosli
Correct I'm using 5v vcc power. So what voltage need to supply?

Thank you ;)

Re: HR202 humidity sensor value output

PostPosted: Thu Dec 10, 2015 2:41 pm
by azhamrosli
Here is my design,value and code....help to get value.

Re: HR202 humidity sensor value output

PostPosted: Thu Dec 10, 2015 3:55 pm
by Nurul.Syuhada
Hi

You can get the humidity value by plotting the graph and do some analysis.

Thanks. ;)

Re: HR202 humidity sensor value output

PostPosted: Thu Dec 10, 2015 8:30 pm
by azhamrosli
Hi Nurul Syuhada,

I'm not understand what so saying..

Nurul.Syuhada WROTE:Hi

You can get the humidity value by plotting the graph and do some analysis.

Thanks. ;)


what to mean to get humidity value by plotting the graph?

my average value is from 0 to 1023..to how to convert to %.. sorry i'm newbie here. :(

Thank you

Re: HR202 humidity sensor value output

PostPosted: Fri Dec 11, 2015 9:48 am
by Nurul.Syuhada
Hi :)

The sensor can only read from 20% to 95%.

so,

value from sensor | humidity percentage
0 | 20%
1023 | 95%

To get Actual RH value:
actual RH value = ((value from sensor/1023)x(95%-20%))+20%

Thanks.

Re: HR202 humidity sensor value output

PostPosted: Fri Dec 11, 2015 11:58 am
by azhamrosli
Thank you...i will try it next. :D
One more question..

HR202 got 2 indicator light (Green & Red), if only red light turn on what is mean?

Note : i use 3.3V Battery DC.

Re: HR202 humidity sensor value output

PostPosted: Fri Dec 11, 2015 1:36 pm
by Nurul.Syuhada
Hi,

Which LED that you refer to? LED near to A0 is for POWER, LED near to VCC is for DO.

If you refer to LED near to VCC, LED will ON when humidity level is higher than threshold level. The threshold level can be adjusted by adjusting on board potentiometer.

If you refer to another LED, it will ON when power is being supplied to the module.

Thanks. :)

Re: HR202 humidity sensor value output

PostPosted: Fri Dec 11, 2015 2:20 pm
by azhamrosli
Thank You...