EmonTH and DALLAS Temperature probes

Hello. I have bought multiple DALLAS DS18B20 this year and none of thme do work with my EMonTH (1.5) while my older DALLAS probes all worked perfectly.
Is there something that changed on to handle the lastest DALLAS components (higher voltage?). Has someone faced the same issues?
Thanks for your feedback.


I’m not aware of any change to the software. Do you have genuine probes? The DS18B20 is a target for counterfeiters, see Ds18b20 and emonTX3CM firmware - post 78 in particular, and the page in ‘Learn’: Learn | OpenEnergyMonitor

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Thanks Robert.

I did read those article already. The first set of probe where from Ebay - so I assume they were “fake” probes. The second set was from Amazon.
The strange thing is that each tie on my EMonTH, the probes are correctly detected, give a temp and the next cycle a zero. It is really difficult to find a trustfully supplier with probe in stock!

I will give the test sketch a go once more on the new batch I’ve received.

I have suffered from fakes on both FleaBay and Amazon Marketplace - they either had a poor calibration, e.g. off set of a 2 or 3 degrees, or the problem you describe, work well sometimed and just return zero the next.

I buy from CPC Farnell now, they cost 4x as much but are much more reliable.

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