Brewpi temperature

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ff13375

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So I finally got my sensors for my brewpi setup. I have them wired up and it is reading the temperature. I have 2 sensors from the brewpi and 1 from a stc-1000 in a cup of watrr. The brewpi sensors are reading 22.4c and 22.3c. With it being a .1 difference is why I then put the stc-1000 prob in the water too. The stc-1000 probe is reading 22.9. I am trying to see if anyone else has had this problem? Also how people check to make sure thier prob temperature are right.
 

alphaomega

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Problem? No, I'd say that is a pretty good result. Hopefully all three are pretty correct (that is that the actual temperature is close to what you measured).
 

thekraken

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I'd say they are all close enough. The DS18B20 temperature probes that my brewpi uses only have an accuracy of +-0.5C. To calibrate you could stick all three probes in a cup of ice water, crushed ice would be better. Fill an insulated cup (coffee mug, styrofoam, etc) all the way with ice, then add cold water, then stir well, add your probes and wait a minute or two to check readings, the ice water should be 0.0C.

If you find the brewpi probes are out of whack you can adjust an offset for them by following this thread: http://forum.brewpi.com/discussion/448/temperature-probe-calibration
 
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ff13375

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Ok thank you for the fast reply. I have another question about temperature hopefully you guy can help me out or explain. So when I put the temperature sensor in a cup of water the fridge sensor changes temperature extremely fast compared to the beer temp sensor. The beer sensor takes a min or 2 to catch up.
 

thekraken

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Ok thank you for the fast reply. I have another question about temperature hopefully you guy can help me out or explain. So when I put the temperature sensor in a cup of water the fridge sensor changes temperature extremely fast compared to the beer temp sensor. The beer sensor takes a min or 2 to catch up.
Hmm, that shouldn't be the case. What probes are you using?
 
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ff13375

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I got them off eBay came in a 5 pack. I even tried switching what sensor does what in the settings but same out come. That what I don't understand
 

thekraken

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I got them off eBay came in a 5 pack. I even tried switching what sensor does what in the settings but same out come. That what I don't understand
You tried switching what sensor does what and the same physical sensor was slow or the one with the beer setting was still slow?
 

FuzzeWuzze

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Ok thank you for the fast reply. I have another question about temperature hopefully you guy can help me out or explain. So when I put the temperature sensor in a cup of water the fridge sensor changes temperature extremely fast compared to the beer temp sensor. The beer sensor takes a min or 2 to catch up.
Yes thats exactly what should be happening?

You put the beer sensor in the water, and i assume the other sensor is just floating in the air in the fridge(as it should be?)

Obviously the fridge sensor is going to shoot up and down drastically as the fridge turns on it will be pumping in tons of freezing air, which will take several minutes to actually effect the beer sensor reading in the water.


One is measuring air which changes instantaneously, the other is measuring liquid which takes a long time to change.

If they are both submerged they should be behaving identically, but then again thats not a real world scenario either.
 

thekraken

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Yes thats exactly what should be happening?

You put the beer sensor in the water, and i assume the other sensor is just floating in the air in the fridge(as it should be?)
I assumed, based on post #1, that all his sensors were in the cup of water for checking calibration.
 
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