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Author Topic: DS18B20 sensors  (Read 1477 times)

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Offline David E

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DS18B20 sensors
« on: January 07, 2017, 09:50:32 AM »
I am putting together a soil temperature setup using a Raspberry Pi and 3 DS18B20 sensors and the excellent dashboard.  I have put it all together and the 3 sensors are sat on my desk and report the same temperature within 0.1 deg C which I'm happy with.

What I now want to ensure is the actual accuracy of the temperature that they are reporting. Does anyone have any suggestions ?  I have a thermocouple that plugs into my multimeter which I put in a large pan of boiling water. This reported that the water was boiling at 95.1*C! So apart from comparing the temperature reported in the office between the thermocouple and the DS18B20 sensors and offsetting them from this, I could try dropping the ds18b20 sensors into the pan to check but it wouldn't be particularly easy.

Should I accept that the readings are correct or is there a better way to check?

Davis VP2

Offline niko

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Re: DS18B20 sensors
« Reply #1 on: January 07, 2017, 03:03:20 PM »
I've tested quite a number of DS18B20's and I think you can rely on them being within the specification which is 0.5C from -10C to +85C.