I have noticed one of the sites I monitor has an issue with reporting the PV generation.
On Sat 15/4/17 around 15:50 the total recorded PV production on 2 separate feeds (phpfina & phptimeseries) reached 10,000 kWh’s and have not shown any increase since, despite plenty of generation. The “solar” power can be seen as expected on all three phases and as a summed total as usual. I also have a “power to kwh/d” feed and that is reading correctly.
As a quick test I added a second “power to kwh” process and feed immediately after the original one, the only difference was this being a new feed it is starting at 0 where as the original is currently at around 10,000 kWh. That started counting immediately and proved the values are being passed into the process ok, and the process is passing that same power value on to the next process ok.
When looking closely at the chart above it is possible to see some slight movement in the “flatline” and when zooming in that becomes more evident.
It isn’t until you zoom right in that you can see there is actually a lot of movement but the value remains around 10,000 but changes with every new datapoint. This is the plot since 07:00am this morning til now (around 6hrs)
during this time the solar power has been flowing and the kwh/d feed has climbing steady. As has the new “2nd” kwh feed I just added.
That line at full magnification is always smooth on all previous graphs and the values can only increase, there is no provision for a “power to kwh” feed to move backwards, and yet it does here!
I believe this to be a rounding issue somewhere, each time the value goes over 10K’ish it is rounded down or truncated and then the next value does the same, resulting in a value that is almost always the same but not quite, it just bounces around the 10k mark.
What is confusing me further is the fact that MySolar is able to detect the “PV today” correctly from the same feeds (solar & solar_kwh, both phpfina)
So I deduce from this that perhaps there is a correct value being held in Redis or memory and only the persisted values are being rounded or truncated etc.
I’m therefore a little unsure of trying a reboot or redis flush as that may lose data that can currently help locate the issue.
Any idea’s ??? Anyone ???
Running self-hosted v9.8.2 on a Pi+hdd.
@TrystanLea or @nchaveiro can you shed any light on this at all? This site was the first of a 20 site pilot so I have 19 more sites a couple to a few months behind this one, but this being a smaller site (generation wise) the other sites will be hitting the 10k mark real soon!
I can provide more charts and data etc.