question

VRM Advanced tab, VE.Bus State widget shows VE.Bus state:

You should see what the inverter is doing and when.

Alarm logs and Event logs below it:

I would guess that you are consuming more power than you can replenish, and the inverter is periodically shutting down and then restarting when battery voltage increases.

Hey snoobler,

Thank you very much for your quick and helpful response.

I haven't set up the VRM yet but now is the best moment I guess.
Your guess may be right, today I found two warnings in the Cerbo panel from the MuliPlus, complaining about low battery voltage.

But I don't understand why. Maybe I am declaring myself to the biggest noob every :D but:

In the morning the battery was at 80% with 13.2V. It is a 560Ah battery so my expectation was I can use the inverter for some time until it shuts down. The only consumers during the night were the router, the Blink cameras and another cam using 230V and cooling fans for the electricity compartment using 12V. All in all around 30 watts. So does this sound like a reasonable thing to do (shutting down)?

In the morning I switched the inverter off manually and on again to no avail, but switching it off and on again in the panel did work. I feel like I am missing something (in knowledge).
The LEDs sequence of the inverter after switching on (when the battery had 80%/13.2V) were as follows:

• at 00:00s green LED on for inverter mode and red alert LED blinking (possibly complaing about low volatge?)
• at 00:15s I heard the relais(?) and the red LED stopped blinking
• at 00:30s secs later the relais clicked again
• at 01:13s relais again
• at 1:20s red LED started blinking again accompanied by 8 clicks (1 sec between each)
• some point later it stopped blinking (I don't know the exact time)

Maybe I am overthinking it but I really want to understand the inner workings a bit better :)

Thanks again for your help!

edit: when the inverter is not operating, no LED is on

Shunts (Lynx, smartshunt, BMV, etc.) must be regularly synchronized to true 100% to maintain accuracy. They must also be configured correctly. If incorrectly configured, a shunt can reset to 100% even when it is near empty, or it can do so prematurely based on charging method and configuration. 80%/13.2V is a decent correlation.

Without having data to go on, it's hard to say. Getting VRM online would be extremely helpful. However, given that you are already working with someone that can connect remotely and fix things, I suspect VRM is already configured. It would be prudent to reach out to your installer to address this issue.

The inverter may be configured to shut down at a higher voltage than you would prefer. One can choose any voltage/SoC they want.

Is the 560Ah battery a custom LFP battery? 560Ah implies it's made with common 280Ah LFP EV cells from China. if this is the case, correct configuration of the LFP BMS needs to be confirmed.

There is a further possibility that the cells of the LFP battery are imbalanced and only ONE cell his hitting low-voltage cut off prematurely.

Worth noting that I'm looking at 80%, 13.2V, 6.1A/81W of charging. LFP voltage is only accurate as an SoC when completely at rest - no loads or charging for several minutes. At 13.2V WITH CHARGING, you are likely below 70% - not a huge error, but it makes the battery % uncertain.

Since I'm only seeing 81W of charging, and you're using AT LEAST 30W continuously, I suspect you are not replenishing your daily energy use, and the capacity available to the system is being consumed, and the system is shutting down.

Thanks again for the insight!

I will need to read up the the smartshunt and how to synchronize it. Also, I installed VRM and will add the devices tomorrow.

After reading a bit, I tend to get a Mk3 device to see what is configured as low-voltage, if it is 13V for example, that would be not really helpful.

Regarding the battery: I have seen in the app for it that it has 4 cells and they all had the same voltage, it is this model: https://ultimatron-shop.fr/Produits/ultimatron-batterie-lithium-12-8v-560ah-lifepo4-smart-bms-avec-bluetooth/

The 81W were the charging in the early morning, during the day ist was up to 380W (I got two 405W panels on the roof) and the SoC was getting up to 95%.

Thanks again, I will get back here with more data once I gathered them with VRM.

p.s. will the data points for VRM be stored on the device? Or are they live readouts? When the inverter powers down my router will also be down and therefore I won't be able to access VRM remotely, does that mean I loose data points?

Sorry for the late reply but I wanted to make "sure" somehow to identify the cause. It "seems" to be a fault due to a loose nut(!). Therefore the current could not flow as expected and I could even provoke some sparks when moving the screw. So I tightened the nut and for 4 days now there are no issues, the current shown in the panel is more to a rational level (14.5V vs. 12.3V before). But all that is based on my non-informed assumptions since electricity is not something I get.