I have 2 projects with a waterproof DS18B20 sensor, but if I use it like this, everything works perfectly. But when I put the sensor in the water, the temperature keeps switching between -127 and the actual temperature. When I take it out of the water, I only see the actual temperature. Have used v…

It'll be interesting to see how it works in a submersible version.

[image] digiton1: I'll just have to deal with the -127 message now and then How to deal with -127: [image] DS18B20 Error +85°C / -127°C – Causes, Analysis, Fixes and Reliable Reading Methods Programming This is the main article of a series of 8 topics, w…

Analog Devices publication. "Guidelines for Long Line 1-Wire Networks"

Hi @digiton1 Do you have a DMM? Could you measure voltage between VCC and GND pins on your sensor module? (in a working state - so with all wires, modules and boards are connected and power switched on, of course)

All the best solutions didn't work, but I think I'm there now. I made a waterproof pipe and it is now hanging in the pool. The first few hours I regularly received a -127 message, but I haven't seen this message again in the past 2 days. I thank everyone for the input and the information, but I’m …

[image] digiton1: but I haven't seen this message again Just use this: [image] DS18B20 Wrong Readings – Safe Temperature Model for Reliable Output Despite Errors Programming This is article 2 of 8 in a series about robust DS18B20 / 1-Wire system design. …

[image] digiton1: The first few hours I regularly received a -127 message Personally, I would not trust anything that was malfunctioning and buy a quality temperature sensor.

Agreed. It's telling you something. Unreliable.

[image] tigger: It's telling you something. I agree that a -127 °C reading is telling you something, but it does not necessarily mean that the sensor itself is unreliable. I have had to deal extensively with DS18B20 sensors in real-world, usually electrically noisy environments. Yes, clones …

[image] digiton1: I made a waterproof pipe Have you bought the water proof sensor of post #46 and have tested it in water?

Wrong temp with DS18B20 sensor

Projects General Guidance

InquisitiveMind August 26, 2026, 9:21am 76

Just use this:

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Wrong temp with DS18B20 sensor

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