Displayed Light Temperature

[Arne]

Hi Rob,

I still have some strange displayed light temp... ;-)
Running v2.94 Beta.

   

   

   

   

[Rob F]

Are you getting that randomly or during startup? Did you happen to copy that file to the Arduino IDE program directory for serial buffer size?

[Arne]

Hi Rob,

Yep, I copied the buffer size file to the Arduino directory on my pc... ;-)
This is a continuing swapping of digits, so not just at the startup.

[Rob F]

Perfect, I'll look into it and get back.

[niksunen]

Perfect, I'll look into it and get back.

Just for info, my temp readings work just fine (version 2.94, first version, so there is no corrections you upload, if this is any mean) 

   

But i have long time ago same kind problem, and water temp show these strange readings also :D And i blame them faulty probes :D Rob do, you remember how i get it fixed?  :D

There is a clue :D Probes somehow get confused if they are diffrent ground potential. So my problem solved, when i added that wire to aquarium water in the controller ground pin. If i remove that those readings start soon get just like Arne's picture. I realized that after i ordered ten temp probe and all show same symptons, but then i realized that if they are not near of aquarium water or aquarium, they work fine :D After that grounding wire, everything works just fine. But I still sees that if i forgot usb cable to controller or display usb port, when i upload software, but this don't mind me, because i always removed usb wire between pc and controller after that

   

[Rob F]

I noticed it once on mine quite a while ago, haven't seen it again but not always looking. :) I think I saw it when it started up that's why I asked that. Good news is its just visual, the data is getting messed up going to display and obviously rare, this has no effect on anything being controlled using that temperature, those readings are direct from the probes so controller always knows the correct temp but sometimes the display is getting confused, if that makes sense. I will get it sorted out though. How often do you get that Arne?

[Arne]

The temp sensor works great.
For now it's only the light temperature that is showing strange digits.

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Rob, I had this in every version, so not only the latest one, if this helps... ;-)

[niksunen]

The temp sensor works great.
For now it's only the light temperature that is showing strange digits.

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Rob, I had this in every version, so not only the latest one, if this helps... ;-)

Yeah i have that both of them, even light temp probe is no water off course :D But somehow that ground cable fixed it to me. I am not saying you might have same problem. Just trying to give Rob so much info that i can, so he can solve this better :)

[Arne]

Interesting Niksun, but I do not want any copper wire in my reef tank... ;-))

[niksunen]

Interesting Niksun, but I do not want any copper wire in my reef tank... ;-))

Yep i understand that :) have you check, using serial monitor, if controller reads light temp right?  And if so, then peoblem is somewhere display or connection code between controller and display

[Rob F]

But i have long time ago same kind problem, and water temp show these strange readings also :D And i blame them faulty probes :D Rob do, you remember how i get it fixed?  :D

There is a clue :D Probes somehow get confused if they are diffrent ground potential. So my problem solved, when i added that wire to aquarium water in the controller ground pin. If i remove that those readings start soon get just like Arne's picture. I realized that after i ordered ten temp probe and all show same symptons, but then i realized that if they are not near of aquarium water or aquarium, they work fine :D After that grounding wire, everything works just fine.  But I still sees that if i forgot usb cable to controller or display usb port, when i upload software, but this don't mind me, because i always removed usb wire between pc and controller after that

I was trying to find who told me about this. :) I wanted to be sure I said it correct. I think that is the problem Arne, this problem has plagued me for ages. If you look back in old posts you'll see it brought up. I remember before I added code so if number went over a certain value nothing would happen, I'll have to make sure that is still there. Can you try it temporary to see if it helps? Maybe using an aquarium water ground probe would be the answer?

[Rob F]

Yep i understand that :) have you check, using serial monitor, if controller reads light temp right?  And if so, then peoblem is somewhere display or connection code between controller and display

I always tried that but it would never do it when the serial was open. If I left it over night the IDE would be locked up, seems to do that if to much data goes in the serial window.

[Arne]

Okay, when I understand correctly, you want me to connect the power supply gnd to my water?

[niksunen]

Yep i understand that :) have you check, using serial monitor, if controller reads light temp right?  And if so, then peoblem is somewhere display or connection code between controller and display

I always tried that but it would never do it when the serial was open. If I left it over night the IDE would be locked up, seems to do that if to much data goes in the serial window.

Is there possibility to use serial monitor using example putty or something, so it wont reset arduino when connects? Because it still prints that data to serial everytime when arduino is running and sometimes you sees this data when connects using  ide serial monitor, but this sends same time that 1200bps command which reset arduino, using putty it would not do it, and you should open and close serial connnection and arduino keeps running, so easier to benchmark etc.

[Rob F]

Okay, when I understand correctly, you want me to connect the power supply gnd to my water?

Yeah, any common DC ground should work, whichever is closest to the aquarium. 

Is there possibility to use serial monitor using example putty or something, so it wont reset arduino when connects? Because it still prints that data to serial everytime when arduino is running and sometimes you sees this data when connects using  ide serial monitor, but this sends same time that 1200bps command which reset arduino, using putty it would not do it, and you should open and close serial connnection and arduino keeps running, so easier to benchmark etc.

I'll have to look into that, it can be frustrating when it restarts after opening serial window.

[Arne]

I'm not a programmer so this might be a stupid question: why does the water temp work correctly and the light temp not?

Rob, these kind of fixes tells me there could be something wrong... ;-)
Ground loop?

[niksunen]

I'm not a programmer so this might be a stupid question: why does the water temp work correctly and the light temp not?

Rob, these kind of fixes tells me there could be something wrong... ;-)
Ground loop?

I thinks that aquariun which are full of water and electronic devices makes aquarium very "noisy" place, electronic aspect i mean. And when you put temp probe there, and arduino and aquarium might be diffrent groundlevel / potential. Just like computer case, it has 115v voltage diffrent to the ground (if no grounded wires/shuko connectors used)  and if you put place like that temp probe, which is ic microchip it can get / "measure"  those interferences and show strange temps, and actualy they are not temps, just temp probe ic faulty outputs. And when there are ground connection wire wich set both arduino and tank same ground potential, those errors are gone. 

Or this is how im think of it. But im not electrical engineer or something, so i can be very wrong :D

Have you try to change those probes between? And see if there is still error in light temp :) if you have faulty light temp probe

[Arne]

Aren't the light sensor ground and the water temp sensor ground on the same level?

[Rob F]

Sorry I disappeared, just had a fire alarm go off in my building which scared the heck out of me, looks like someone pulled the alarm.

Anyways, these are cheap sensors, there are better ones available that don't cause issues, soon I'm going to add the code so Atlas Scientific temp circuit and probe work. I've read these can cause interference, not sure where it comes from though. Here's some possible solutions I found.

You have 100nF or similar decoupling capacitor between 5V/Gnd at the sensor end of the cable?
You have a strong pullup (2k2 perhaps rather than 4k7) between 5V and the data line at the Arduino end of the cable?
You run the data and ground on the _same_ twisted pair of the Cat5 cable?
All of these precautions should reduce chance of interference/noise corrupting the signal on the OneWire bus.

[Rob F]

I just added a solution that should work, its in the code used for the probes. Now if anything comes out of the sensor greater than 100.00 it will discard it. You can download it now and try that. That should fix it and only allow proper readings to be used.