I'm using latest Dashboard v. 2.19.4.
Gauges/Donuts work very well when the range minimum value is not negative.
In my case I'm using a dashboard flow to display the electric power exchanged between grid and solar PV panels in my home. When you produce more than you consume the ehchange value is positive ( you are selling energy to the grid), whereas it's negative if you consume more than you produce ( you are buying energy from the grid). So, when setting up the node, a negative value has to be inserted in the minimum field, say -6 kW and +6 kW for the maximum.
In this situation the gauge/donut display is very unintuitive, if not misleading. For instance if no power is echanged (payload =0) you still see half sector filled with color and you may think that half power of total range (-6 kW-6kW) is exchanged while it's actually 0!
As you can see in the following screeshots the gauge rapresentations with power = -5kW, 1kW and +5 Kw are equally not meaningful. For instance, if you are buying 5 kw from grid, you just see a tiny red sector whereas it should be at its almoust maximum extension:
On the right side of every screenshot I have proposed what in my opinion should be the correct representation.
What I'm proposing here is a sort of "differential" gauge.
It should have following behaviour when a negative minimum value is set in the minimum field :
- with value = 0 the needle is in vertical position ( a "zero" digit on central top of gauge would alse be nice to have)
- with value < 0 the circular sector is drawn counterclockwise starting from zero vertical position
- with values > 0 the sector is drawn clockwise from zero.
Is this behaviour achievable with some particular node configuration/tweaking? if so please help me.
If not, I'm proposing to the Dashbord/Gauge team to add this new "differential" appearance. From a UI perspective it will suffice to add in existing node configuration window a checkbox "Use differential appearance", enabled only when a negative value is inserted in the Minimum field. So you can keep actual behaviour if you like it more.
Note: I also had screenshots of 1 kW and 5kW scenarios, but I couldn't post more than two images here. I will if someone is interested in the topic.