In order to automatically read out my energy meter, I flashed Tasmota with SML support. So there are three values that a pushed via MQTT (with examples):
power: 322
count_neg: 18.255
count_pos: 50.714
(“50.714” indicates, that 50714 Wh where used).
These values are pushed as a JSON-string and I was able to extract those three counts and assigned them to three items:
power => number:power
count_neg / count_pos: number:energy
Power is absolutey fine, so I’m getting a chart out of it like this:

But the other both are just empty. What I added is a pattern (%.3f kWh) in state description. So basically looks like this, which is fine…

But then, when I click the number, the chart is just empty

What am I doing wrong?
I’m running OH3.2 in a Docker container on a Raspi4 (4 GB) with mysql persistance.