My seplos batteries do not have such an emergency mode. In theory i could then also hook them up to my computer and lower some of their voltage levels. It’s just something to keep in mind, I feel like turning off the circuit breaker off all consumption devices make most sense in such a situation. It’s just the fact that it is manual is something that bothers me, but I know that if I want to I could program something on node red.
It’s not as much out of necessity, it’s just hypothetically speaking. I could also hook up my 12v 280ah battery with a boost converter to jumpstart the batteries again. The thing is also the generator is manual and you still need to top off gas once in a while, but in a winter/war where the grid is potentially down for months also this is not a permanent solution. A better solution would be a victron inverter that shuts down when SOC is lower than 5% and then uses the 5% remaining SOC to probe 1x every hour for 1/2 minutes (from 11 till 15) or longer depending on solar forecast in the middle of winter and (8 till 18) in spring to see if the solar inverter is producing enough power to charge the batteries.
All of this is last resort, You don’t want to end up in a situation like this. you would always try to only use whatever you have, but it would be nice knowing that in case of user error when there is over consumption in the winter the system has a function to self boot up again. Instead of getting stuck.
Do you have room for a small array? You could use a 100/20. If you use 4x100w panels should get about 70V which is enough to start charging. If you are getting low voltage disconnect on a cell there is usually one that is around 2.6V and the reset will be sitting at 3V. It takes only a couple amps 100-200W to quiclky increase the voltage high enough to get above the recovery voltage.
If tou turn off switch as group they will stay on
Charging with tour car battery is easier if you use a skylla as charger
The great thing about Dutch is that every 4th or so word is pretty close to english if you look at it sideways 
eg Het water in de tent was warm.
Lars: Also consider what happens in your battery - often a system will end up with multiple levels of “off”
For example, as SOC goes down on one of my demo systems;
~20% - inverter turns off, so no more AC loads
~15% - the Battery Protect turns off a DC load (based on voltage, so a little hard to say exactly what SOC this is
~10% - the BMS in the battery takes the battery off-line by disconnecting the positive terminal from the cells. This might happen at different times as each battery makes its own decision. Once the BMS is in protection mode, it requires a charging voltage to come out.
This is where we make sure that there is an mppt in the system with a couple of panels that will blindly start charging as soon as the panels see some sun. This is not what happens in a Growatt system - the Growatt won’t start charging until it sees that the battery is “there” and “comms are up” - well comms won’t be up until the battery is out of protection mode, and you can’t get out of protection mode without a charging voltage, so you are stuck in a lock-out condition.
The Victron MPPT resolves this by bringing the batteries online early in the morning, which then starts up the Growatt, which then will start charging the battery from a much larger array.
A similar condition exists if you power a GX from the AC output of a MultiPlus - the MP won’t output AC until it sees the GX, and the GX won’t be seen until there is some AC power.
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Waarom zou je een 25A oplader van 875 euro kopen als er een 70A lader gratis in je multiplus zit?
Ja das waar! 
Use a normal 12V lead-acid battery that is completely insensitive to cold and is charged via a small separate charging circuit. The Victron system works with this for months without any problems and is completely separate from the LiFepo batteries …
Yeah I totally understand this. As of right now, the Victron will stop discharging as soon as 1 of the 3 Seplos batteries gives a low battery warning/error(when one of the 48 cells hit 2,8V) However this is still before it disconnects the positive terminals. As the Cerbo is hardwired to the battery and is still staying on. Also the device manager is still telling me that 3/3 batteries accept discharging at this moment. So there is still technically juice left in the battery, but this could maybe give me 10 min of runtime if all devices are still connected. But there is not a magic button or some code that turns on the inverter long enough to start the inverter. So then I would still have to charge the batteries long enough such that i can have a few min of inverter time to start up the solar inverter again.
I agree that a simple mppt controller would be optimal such that there is always a bit of power to start the inverter and thus the larger panels, but as of right now it is not worth the effort to drill big holes, modify ceilings etc to put down a few dc wires, especially as i am living in a country where since i was born i have not had a grid outage(except for 1 planned one).
You could probably grab a 100/20 or similar cheap MPPT (whatever matches your array Voc) and just wire it to your battery with a breaker - leave it off, and if you ever needed it, just unwire your main array and connect the MPPT for 20min, then swap back. An investment of 50 euro or so, but a solid solution should you need it.
Here is a node red flow that might work. I have written a function that will check the SOC and the incoming message for AC in. If the SOC is above 5% and AC in is active set the inverter power to 9000. If the AC is not active and SOC is below 5% set the inverter power to 0. I have put the JSON code is a text file if you want to try it.
CHECK AC IN AND SOC.txt (7.3 KB)
Sorry, ignore me if i get too much off-topic here but i cannot resist…
What type of Dutch home you living in? must be a mega sized mansion with consuming that much energy or just very, very badly insulated? on a cold winters day in the Netherlands with -10 Celsius i expect a COP of at least 2
which means 80 kWh of heat energy on that cold day…
And:
I would have something else to worry about than consuming that much electricity for heating. Maybe you should take a holiday and travel some 2000km east crossing just three borders and ask the people what their priorities are at the moment ?? (take some medical items with you on that trip, they will be happy to receive them!)
And now on-topic:
I would get a external loss of mains detection and switching to create a island so you can install a dumb cheap micro solar inverter without LOM on the input side and let that be the frequency source for the MP2 in such a situation. looking on the map you are not so far away from the border, so you can order that kind of stuff with the VAT exemption Germany has
Ahaha no don’t worry.
With the 40kwh i was talking about total electricity usage. This also includes, a beefy desktop pc and a few big other machines like laundry and dishwasher. Naturally in case of a power outage you can cut down a lot of this usage. With regards to the heating, our home is a pretty standard duplex house with a seperate garage and a small extension from our home for the kitchen etc. It’s not a big home but old as it is build just after the second world war. We have hr++ glas and inserted extra stuffing in between both brick walls. On cold winter days which you were describing we would typically use about 8 cubic meters of gas when we heat our home to about 19 degrees. I think right now on the colder days we use about 20-30kwh of electricity to keep our home a comfortable 20,5 degrees. Which is definitely high, but i think this explains why our energy usage is quite high.
With regards to these scenarios, it is very unlikely for the dutch grid to collapse for several days. The scenario of the grid going down and the batteries running down within a day is not unlikely if we don’t alter our usage what surprised me was learning that if this happens the system won’t restart eventhough there might be enough solar, im fully aware that in case of war, this would be one of the last things we have to worry about.
This is only usefull in case of such an event, i do agree that this suggestion would work in such a scenario, but as this scenario is quite unlikely and there are some manual work arounds ill take my chances 