OpenEnergyMonitor Community

Newbie Feed / Graph Help Please

Got my EmonBase and EmonTx installed in the garage today, all talking together nicely and very easy to setup.

I have 4 consumer units in my property that I want to monitor, I’ve connected the CT’s to 3 of them thus far. (Looks like I picked up the Neutral on one as it measures in negatives).

In addition to the individual feeds, I want to see the total on a graph. All I have setup right now is to log the feeds in Realtime Watts.

I then created a Virtual feed that add’s the inputs together. This shows the right values when I look at it in the feeds page. However, when I try to view it in the graphs, no matter what time period I view, I just get a straight line from bottom left corner to top right corner and the value goes up into something like 2.4 million.

What am I doing wrong please?


You haven’t shown us any processing, but at a guess, I would say you should probably be using +feed not +input in the virtual feed as input data is not retained so it would be difficult to graph with anything but the current inputs (hence the realtime value on the feeds page looks ok).

[edit - And there must be a source feed to start with, eg source feed Basement CU, +feed Garage CU, +feed House CU, +feed Utility CU]


Or you just got the CT orientated the wrong way on the right wire, if it’s on the right wire, the easy fix is to flip it 180 degs (so the cable passes through it in the opposite direction).

Hi Paul,

So as far as I know, I’ve not done any “processing” per say at this stage, simply just logged the feed then created the virtual feed.

Ive changed it from inputs to feed as per your suggestion (and with a source feed), but I’m still seeing the same issue. Any other ideas?


Ahh thanks for that, I didn’t notice an orientation on the CT, but I will check that also. It was too tight in the CU to get the CT on the incoming cable, so I had to find the tail in the back of the cupboard and they are both grey cables!

It looks like you have used a +source feed not started with a source feed,

note there is no leading plus sign on my “sfeed”

That’s sorted it, thanks very much Paul.

So I think I get the difference between sfeed and +sfeed. But whats the difference between +feed and +sfeed?

Thanks again.

TBH I’m not that clued up on virtual feeds, just snippets I picked up along the way.

@nchaveiro might be able to answer the more technical stuff when he’s passing next.

The + means that it will sum up the result with the previous one.


I get the purpose of the +. But I was wondering what the difference between feed and sfeed (source feed) is?