Adding power from differents devices

Hello,
I’"m trying to add 2 power feeds in differents deices. Here are some archived discussions:
https://openenergymonitor.org/forum-archive/node/12221.html
https://openenergymonitor.org/forum-archive/node/10555.html

I follow also the process creation here:
https://guide.openenergymonitor.org/emoncms/postprocess/
I use two devices : emonpi power 1 ( power RDC) And EmonTX power 1 ( power Voisine). I want TOTALpower= power1emonPi +power1EmonTX.


I Try two ways . At the end :
first solution : a new inputs appears in emonpiInput. But it does’nt take account of Emontxpower1.

Second solution : I create a new virtual device. But power stay at 0. no additionss.

Before going more in details :

Do i need to add a new inputs in wich device? , or add a new virtual feed only?

Rémi

I am not an emonCMS expert, so there might be a better way. What I would do is, in one of the inputs (it does not matter which), after the final “Log to feed”, continue with:

Reset to Zero
+ input [one of the inputs]
+ input [the second input]

[any other processing]

Log to feed [the combined feed]

I think +feed is preferred to + input, but that assumes you have feeds for both sources.

Reading Virtual Feed - Post-processing data on the fly | Archived Forum, it appears that you can only use a Virtual Feed in a Dahboard or a Graph. It specifically states that it cannot be sent to a (real) feed. (Unless that has changed in a later version.)

Thanks for your link.I want use the result in app or graph. Thus virtual seems to be ok. But It is not so obvious… and version are newer.
I don"t understand where I should add your code. I’d like to keep the emonCMS solution if possible. I’m surprised that people using emontx don"t have this issue.

Read this again:

Thank for you answer : good help for me.! I’m newby… I begin to understand that we can play with data… and add many operation before log the results.

We all were newbys once, it’s nothing to be ashamed of, and the best way to learn is to play with the data. You sometimes need to be very inventive when you manipulate the values. When you click an operation, read the text in blue, because that gives a brief description of what the command does.

You didn’t need the Reset to zero and you didn’t need to add emonpi:p1, because that’s automatically there at the top of the list.

So you could have had

1  + input Node  emontx3:power1
2  Log to feed   emonpi:powerRDC

But…
If you had wanted to log emonpi:p1 separately, and you had done other things first that made the number that’s passed down the list different, then generally you do need a Reset to zero so that you can start again.