Robo Tank, temperature probe errors

[kdx7214]

I received my Robo Tank (thanks again Rob!!) and love the unit! I hooked up a temperature probe (forget the # on it, but it's the one used by reef-pi) and it's generally working pretty well.

The problem is that every now and then, it's showing the tank goes from 79.9F to -0.91F in an hour, then jumps to 39.9F, then back down to -0.98F, then back to normal finally.

Anyone have any idea what could be causing this? I have another separate thermometer and it shows the temperature is stable at those times (between 79F and 80F).

Thanks!

 

[Projects with Sam]

That looks like its for a while too, not just a few blips. could the thermometer have fallen out of the water? Or could the water have dropped?

 

[kdx7214]

That looks like its for a while too, not just a few blips. could the thermometer have fallen out of the water? Or could the water have dropped?

The time increment on that is only an hour for each spot, so basically it's saying it did that in an hourish. If the probe had fallen out of the water it wouldn't have ever recovered. The water level is still okay today and I've not added anything.

Just curious as to what the heck is going on. Maybe an iffy probe?

 

[robsworld78]

I received my Robo Tank (thanks again Rob!!) and love the unit! I hooked up a temperature probe (forget the # on it, but it's the one used by reef-pi) and it's generally working pretty well.

The problem is that every now and then, it's showing the tank goes from 79.9F to -0.91F in an hour, then jumps to 39.9F, then back down to -0.98F, then back to normal finally.

Anyone have any idea what could be causing this? I have another separate thermometer and it shows the temperature is stable at those times (between 79F and 80F).

Thanks!

Hi, glad you got it but not that it's giving you issues, has it done this again? It is a little strange that it looks like it slowly dropped, slowly came back up, then down and finally back up. As mentioned a faulty sensor normally does quick -1 and then goes back but it could still be a bad sensor, if you got it from me let me know. Also make sure the sensor cable isn't running across any AC cables, that can cause interference.

 

[kdx7214]

Hi, glad you got it but not that it's giving you issues, has it done this again? It is a little strange that it looks like it slowly dropped, slowly came back up, then down and finally back up. As mentioned a faulty sensor normally does quick -1 and then goes back but it could still be a bad sensor, if you got it from me let me know. Also make sure the sensor cable isn't running across any AC cables, that can cause interference.

I don't think it slowly dropped. Right now I have it set to only record data once an hour. According to the times on the graph peaks are on the hour. That means the slope you see was just the graphing code interpolating between the two values.

I honestly don't know if I got it from you or elsewhere lol. I sort of piled things up when I got them and it all got mixed. Most likely I didn't

I'll keep an eye on it and if it goofs up again I'll just get another one. It's not like they're expensive or anything

Thanks!

 

[Ranjib]

logging data once every hour could be very slow. i use 5 or 15 seconds

 

[kdx7214]

logging data once every hour could be very slow. i use 5 or 15 seconds

I'll change that and see how it goes. Thanks!

 

[robsworld78]

I don't think it slowly dropped. Right now I have it set to only record data once an hour. According to the times on the graph peaks are on the hour. That means the slope you see was just the graphing code interpolating between the two values.

I honestly don't know if I got it from you or elsewhere lol. I sort of piled things up when I got them and it all got mixed. Most likely I didn't

I'll keep an eye on it and if it goofs up again I'll just get another one. It's not like they're expensive or anything

Thanks!

That makes sense why the graph looks as it does, my guess is at the hour when it read -1 it was the last value read so it got saved in the graph. If it continues to do this try another sensor if possible.

 

[kdx7214]

That makes sense why the graph looks as it does, my guess is at the hour when it read -1 it was the last value read so it got saved in the graph. If it continues to do this try another sensor if possible.

I changed it to read every 15 seconds as @Ranjib mentioned and it is still working solidly. Just that weird blip and it's stable, so I'll give it a bit and see how it goes.

Thanks!