Ah, and I’m guessing it’s not possible to have an automation make changes to the times of the scheduled charge?
So does that mean that once the batteries are fully charged the MPPT’s will essentially shut down until the charge window is done?
^^ this! I really think that this is something that would solve a lot of capacity anxiety issues. I guess the crux to this is that people would still want PV to power non-essential loads, but not use batteries for these loads.
Definitely not unique. I know a couple of people who (mainly due to cost) sized their banks to be able to get through a 2 or 4 hour load shedding period without making any behavioural changes (knowing that the water heater and pool pump won’t run) or the minimum required for the inverter.
Just a disclaimer. I don’t have any equipment just yet and I’m just here to learn and dish out advice of what I’ve learnt over the last couple of years.
Nope, as far as I am aware there’s not modbus addresses (or whatever the technical term would be) for scheduled charging.
This is what I’ve noticed on my system, more or less. The MPPT doesn’t completely idle, but doesn’t ramp up nearly as much as it can and I end up drawing a lot of power from the grid. Though @plonkster indicated that this should not happen, it is what I’m experiencing and I don’t really have the technical knowledge to troubleshoot…
Yeah, even if you size it to go completely “off-grid” with essentials (which is largely what I’ve done), you won’t have the capacity to carry the non-essentials.
That, but also something called legacy. For every change, you must make sure you don’t break how it used to work, and that the new behaviour still fits what one might call the “design language” (if I can import some car terminology).
The design of the ESS self-consumption setup is that you’re trying to always eliminate as much as possible the cost of importing electricity from the grid. The Multi WANTS to be in self-consumption mode as much as possible, and when it cannot be (because the battery is low), it goes into the lowest power state possible to avoid further discharge. The idea of an “idle” mode where it just sits there implies a third state that things can be in which does not fit the design language well. There are ways to make it work, eg Scheduled Charging with a Low SOC target, or your own automation, but it is not built into the firmware. Adding it requires careful thought…
… what I’ve done is split my DB,
input bar,
Non Essential bar
Essential bar.
then wired it so that the inverter only feed the essential bar, not can push back to the non essential if there us grid, if grid drops, then non essential is dead.
Also connected everything on the non essential as a pair of switches, “isolator”, contractor => load and then I drive the contractor from a Sonoff, this allows me to run automation (HA and Node Red) on these non essentials which are pool, 2 geysers and a stove.
G
