Cable length
I bought 6 temperature sensors for building my new brewery. It has taken quite a lot of time, as these were acquired at the end of 2021.
Waterproof OneWire Temperature Sensor extra long (RJ11, DS18B20).
This week I got to test the sensors, and due to cabling I needed to extend the cables with simple RJ11-male to female 5m cables (name: RND 765-00139). That worked surprisingly well. I can not see any shift in the measurement compared to direct connection to the Spark 4.
Success
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Sensor showing high temperature in a cold room
However, one of the sensors was showing 85 degree, increasing to 90 degree while testing. I never deared to test this one with the extension cables. Also the other sensors at the same Brewblox-module was not working when this sensor was connected.
I started to search this forum and found this thread by Elco explaining problems that could occur with the temp-sensors:
https://community.brewpi.com/t/troubleshooting-temperature-sensors/14
From what I read there, the sensors could heat up if the cabeling was wrong. Testing again, I found the sensor to be extremely hot. Therefore, I guess the conclution is that the cabeling within that spesific sensor is faulty.
Luckly I ordered 6 sensors even though I just needed 5.
Problem found
I will post some pictures when the HERMS brewery build is finished. For now, I just have a picture of the control-cabinet in its current testing phase. You may spot one of the white extension cables for the temperature sensors rolled up in the middle of the picture underneath the Spark 4:
