Best way to report both negative and positive values

Is there a workaround to get a center zero gauge or histogram?

I want to monitor/report on Net Energy. If generation from solar panels exceeds consumption then we are exporting (-ve) otherwise we are importing (+ve).

I have seen other questions on centre zero guages but not found a way to to do it - how have others solved this problem?

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Welcome to the forum.

What is your datasource and which version of Grafana are you using?

Hello Grant, thanks for responding

Datasourse is influxDB v1.8 which receives data from my energy monitor (IoTaWatt)

Grafana version is 7.5.5

What I am aiming for is a dial that runs from (say) minus 10Kw to + 10kw with zero in the centre. The color (reading) should then from the centre towards the left if negative and from the centre towards the right if positive.

A histogram would work for this use case (instead of a dial) but if I set the histogram limits from -10 to +10 and have a reading of (say) 2 then the bar starts at -10 and runs to 2 instead of starting at zero and running to 2.

is there a way to say ‘start the bar at zero rather than the minimum’ for a histogram?

I think this works if you upgrade to Grafana 8.1:

In InfluxDB 2.0 Data Explorer:

Thanks for coming back so quickly, The Data Explorer view is close and might do the trick.

On your normal gauge the colour is starting at -15 (the gauge minimum) and not at zero.

Here are a couple of examples (I’ve edited your 6.73 gauge) to show what I am trying to achieve.

The bar also centres on zero and extends left and right from the zero (clumsy excel chart)

I’m hoping that there is a setting that I’ve missed…

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Hmmm…I cannot find a way in Grafana to change the bar as you indicated in your screenshot:

Maybe a future update of Grafana will address this? (any Grafana staff want to to chime in?)

I do not know if InfluxDB 1.8 offers any charting tools like 2.0 does, but give it a try, or post your question on the InfluxDB forum.

Implemented it. See my pull request: Setting the neutral-point of a gauge by sfranzis · Pull Request #53989 · grafana/grafana · GitHub

@sfranzis Thank you coming back to this thread to let us know.

Hopefully it will be merged and available to use soon.