My solar panels along with MPPT 150/70 are powerful enough to run my essential loads subpanel (fed from Multiplus-II 24/5000 output), but they don’t provide enough energy daily to keep it running in fully off grid mode, and I can’t add more panels.
What I did to receive the maximum potential solar yield given the circumstances - my home automation system disconnects the AC input from the Multiplus, x hours (x depends on season and on workdays/vacations routine) before sunrise, so that the system runs off-grid and the 10kWh battery drains just enough to let the whole potential upcoming daily solar energy in. The AC input is then reconnected in the afternoon, to finish the charging process and to support the loads until next sunrise.
This works well, after some trial and errors around the optimal timing.
My question is - how can I tell how much energy is actually consumed daily by the AC subpanel and the DC subpanel?
Within VRM Portal, there are some useful fields regarding VE. bus system, like Energy ACin1 to ACOut and Inverter to ACOut, but they seem to accumulate for weeks or up to inverter’s uptime, unlike the Yield Today field of the MPPT Smartsolar that resets itself by the day, which is very useful. The same behavior applies to the Smartshunt that monitors the DC Panel. Is there a way to tell how much energy is consumed solely by the AC/DC essential loads on a daily basis?
There is a Cerbo-GX in my system, and I use custom widgets in VRM portal for data observation. I access the fields mentioned earlier through VRM web interface, but I don’t know whether it’s possible or not to reset them on a daily basis so energy counts are all zero each morning.
So, I pressed it at close to midnight, and at the same time, I reset the kWh History of the two Smart Shunts which measure my DC loads and my AC charger accordingly,
and, after configuring a custom widget, here is the energy balance of my essential AC and DC loads for a single day:
(this is not a typical day, today I’m also doing an experimental battery discharge down to 20%. I have newely configured my home automation system to reconnect the Multiplus-II AC input to grid right away if it senses the battery monitor’s relay closed, which should happen at 20% SOC.
Also, the AC charger should start charging the battery at the same level, as it would sense the Cerbo-gx’s “Generator auto Start” relay-1 closed.
I’m not sure whether or not the Multiplus-II will also charge the battery, or will it enter “Sustain” mode as it always did so far, as the battery always ended the day with a good amount of charge.
It will be interesting to see the logs in the morning… Hope that both scripts will work as expected, so that AC in and AC charger are both triggered at late night hours.
I would like to find an more automated way to reset the kWh counters, preferably with a command line prompt or similar, but my way still works for a one at a time experiment.
