EmonTx3 v3.4.3 not working with temp sensor

I have just purchased 3 temp sensors from the Emon store to work with EmonTx3 v3.4.3 which has been untouched for at least 6 years (it’s been used with a single CT clamp for all that time!).
To try to remove any uncertainly of RJ45 and breakout (which I purchased years ago but never used), I am connecting one sensor directly to the terminal block on the EmonTx. The temperature values all show “300” which I understand is “sensor not detected”. Tried a couple of sensors, each on their own, same result. And yes, I did reset the EmonTx many times.
Should the DS18B20 sensors purchased today work with this generation of EmonTx h/w and s/w ?

Welcome, Mike, to the OEM forum.

Yes, they should do, but are they enabled in the configuration menu? This is the default, but it might have been changed.

But when I look at the "JeeLib “Classic” version of the sketch, I see it has been changed with the note:

V3.4 05/01/21 Slow down DS18B20 conversion - required for new batch of RJ45 temp sensors

which suggests to me that your sensors might well be out of spec, but emonLibCM - which I would expect you to be using - should not have this problem (or at least, it’s not been reported to me).

Thanks Robert.

How do I check they are enabled in the configuration menu ? Is that accessed on the EmonTx itself, or is that within the Emon s/w running on the Pi ?

How do I check if I am using emonLibCM ?

If you connect your emonTx to a computer via a programmer, and use a standard comms program (or the Arduino IDE), the configuration should appear and it will probably mention emonLibCM (or just CM) if the sketch is using it - which it most likely is anyway.

Later versions of emonCMS (on your RPi) will also communicate with the emonTx, but you still need the programmer.

It might be possible to infer this from a detailed knowledge of the output as seen in the emonHub log, and this does appear on the Pi - or specifically accessed on the Pi via your web browser…