Sensor Temperature with thermistor


#1

Hi all .
I’m new in Cayenne .
I sue my Arduino UNO with Ethernet sheald WizNet5100 and make sensor using thermistor 10k.
Now show value for example 332 … it’s 33.2 celsius ??? why not use correct decimal point ??

regards.


#2

Hi
What do you use the code?


#3

standard code from dash board . … I just add new sensor temperature , set pin … etc …


#4

Do you have any screenshot dashboard?


#5

here is it


#6

Try to change the Graph widget on Value widget


#7

same reslut


#8

When you heat the thermistor, value changes on the dashboard?


#9

yes of course … all working … only decimal point is in bad position … if show value 357 it’s look like 35.7 … that all …
any suggestion …


#10

So I do not know, maybe it will know @bestes @adam @rsiegel @kreggly


#11

ehm… I try flash code to arduino with little changes … :
Cayenne.celsiusWrite(VIRTUAL_PIN, thermistor.getCelsius()/10);

but show same value…


#12

Weird. That should work. Maybe do your calc outside the write function and dump the result to the serial port to be sure.


#13

I tried it and worked me correctly.


#14

hm… paste code here or send to me hex file …
I try print value to serial monitor … but not working … I don’t know why …

I add to CAYENNE_OUT

this : Serial.println(thermistor.getCelsius()/10);
but with no result…

10k NTC sensor from 3.3V to A2 input , 10k resistor from GND to A2 input , I use Arduino UNO R3 (clone) with Arduino 1.6.8 IDE , windows 7


#15

You should connect it to 5V


#16

then value change to 538 for example…


#17

try divide by 100?


#18

Ultimately though, if you are using the thermistor.getCelcius, the library thermistoe.getKelvin needs ro be modified with your Steinhart-Hart constants for that thermistor to be accurate. Either that or copy the functions in thw thermistor library to your code and modify.

Search the forum, I’ve already shown how.to do this.


#19

Hi. ehm… now it working …
what is wrong ??
I use Connectivity : Analog and this bad , right is Virtual and set pin …
I do it in my code , Analog read value directly from ADC , but virtual convert it after read …

Thanks fro your time …
Now working …

best regards.


#20

I apologize to all , I’m new on it … don’t know how it work …

thanks for your time …