I have recently setup an emonPi solar bundle and a tx unit. All is going well so far.
At the moment the Tx inputs P1-P4 are publishing correctly to their respective feeds, however I am missing the USE feed. I am expecting the USE feed to be a total of the values from all 4 inputs. Is my thinking correct? if so how do I go about getting all 4 inputs into 1 feed
I don’t know the details of emonCMS, however if yours is a “Type 1” installation and the four c.t’s are each monitoring a separate consumer unit, or separate distribution circuits from a C.U., or a combination of those, then you will indeed need to sum all four.
The best way is, in the input processing of one of them, after you’ve done whatever individual processing you need, then if the value of that feed has been modified (or if you’re not sure)
add: Reset to original
then for each of the other 3 feeds, add + feed picking each in turn from the drop-down list
and finally Log to feed which will be the total use feed.
(Note: you’re not restricted to the four emonTx inputs, you can add in an emonPi one as well - but you might see anomalies because the two devices won’t report at the same instant, so the values will relate to the powers a few seconds apart. Also, the “Reset…” isn’t needed if you have not modified the value on the way down the process list, except of course if you’ve ‘calibrated’ it with an addition or multiplication.)