RESOLVED: Chart with 2 different units of measurement


I’m trying to create a chart that displays my calculated DeltaT item (which is outside temperature minus inside temperatures averaged) in relation to my heatpump power draw which is in watts.

Now I created a chart in the pages menu, and I can add those two items to the grid but openhab seems to throw everything on the same scale. I also tried creating two different y-axies but I can just name them and I also can’t assign y-axies to specific Items.
Unfortunately I could not find any information on this in the documentation. Am I missing something here?

At first I thought maybe my DeltaT item is not properly defined but also if I use the outside temperature sensor data directly it behaves the same way. Somehow the chart mechanism is not able to grasp that there is two different units of measurement involved.

Is there any was I can tell it to do what I want it to do?

Charts seem to work like a charm when I create ones where all the units of measure are the same. But Temperature vs Power doesn’t work somehow.

Cheers audiocrush

You should be able to. This is done through the configuration dialog of the series itself on the graph page:

So that’s what was meant with that :smiley:

Thanks a lot. Works like a charm now :slight_smile: