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Emon CMS web negative values - eg feed in

I’ve noticed that when PV system outputs to the grid, the values go negative - but the chart on the ‘my electric’ web app only shows down to zero.

The android mobile app shows the negative values nicely.

What I’d like is to see the negative ( feed in ) values in the line charts,
but the have 2 sets of bar charts, one set only showing power taken from the grid (eg what i’ll pay), and one set showing power fed back into grid (what I’m giving away that I could try and use)

Is there a way of setting this up?

I’m no emonCMS expert, what it sounds as if what you need (not knowing exactly which charts you refer to) is to use the conditional statements on the Inputs page “Allow positive” and “Allow negative” to set up a separate feed for each.

In very rough terms:

Log to Feed [Nett_Grid]
[any other operations]
Allow positive
Log to feed [Import]
Reset to ZERO
+input [the original input]
Allow negative
[any other operations]
Log to feed [Export]

Thanks - I didn’t notice the ‘allow positive’ / negative on the feeds.
Also - the Reset to Original is the one I need after logging one of them to a feed.
I’ll have a go at setting them up later

Hello @jonshutt, the MyElectric Y-axis is limited to 0 hence why you are not seeing the negative values. This app is only designed for home consumption. Could you use the My Solar app?

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Hi there - although I have solar PV I’m not yet monitoring it as I need to do some stuff for that. But I’ve set up a flow to take on positive, to get the usage from the grid, then take only negative to log the power fed back to the grid, and added substract from zero to convert the feed in values back into positives so that charts can handle it nicely. So now I have 3 apps - one showing the full in and out, one showing ‘in’, and one showing ‘out’