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anttikan avatar image
anttikan asked

Battery SOC 0% - EcoMulti does not switch on

Under a heavy load (charging an EV), EcoMulti installation somehow allowed the batteries to deplete and the inverter/charger (MultiPlus 24/3000/70-50) switched off. It does not even pass thru power from the grid or PV to power the AC loads.

On the inverter, the "Mains on" and "Low battery" LEDs are blinking. According to the Victron Toolkit App, this means, that the system is in sustain mode.

The battery (2 x LiFePO4, 12.8V/90Ah in series) SOC is 0% and voltage is 14.24V, which sounds seriously low.

The Color control is also switched off, but by powering it up with an external power source, I managed to boot it up and see the status of the system. There, the inverter is detected, but is off and cannot be switched back on.

I was also able to connect to the inverter with VEConfig and MK2 to USB interface, but did not find any solution there, either.

Is there any way to get the system back on?

Are the batteries completely dead? Is there any hope to recharge them with an external charger?

battery charging
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2 Answers
Daniël Boekel (Victron Energy Staff) avatar image
Daniël Boekel (Victron Energy Staff) answered ·

Hi @anttikan

Without knowing what settings you are using etc. It's not possible to give a good answer.

Can you share the Inverter settings?


about the deep discharged batteries: can you still connect to hem via bluetooth? what are the cell voltages?

You can try to -slowly- charge them, with no more than 0,1A (100 mA) in the beginning, when cells are above 2V you can go a bit higher (0,5 - 1A)

if you don't have an adjustable power supply with current setting, please get an electrician to help, or you dealer / distributor.

A charge with higher current -will- destroy your batteries permanently!

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anttikan avatar image anttikan commented ·

Thank you for your very quick reply @Daniël!


1. Is there a practical way to see and list all the inverter settings at once so I could paste them here?

The installation was done according to these instructions:

https://www.victronenergy.com/live/eco_multi:start

And the Inverter was setup with VEConfig using the Self consumption Hub-2v3 assistant.


2. I have access to an adjustable power source so I'll try waking the batteries up. Thanks for the advice. What would be a good charging voltage?

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Daniël Boekel (Victron Energy Staff) avatar image Daniël Boekel (Victron Energy Staff) ♦♦ anttikan commented ·

try to charge to 10V first, keep an eye on cell voltages (as soon as you can connect with bluetooth to read them)

the discharge voltage in the document you sent is -way- too low, please read the battery manual about keeping enough remaining charge in the batteries at inverter shutdown.

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anttikan answered ·

Thanks to @Daniël's advice I was most likely able to recover my batteries and get my installation back online.

I disconnected both batteries from MultiPlus inverter and started charging them one at the time with an adjustable power supply, using a very modest current (0.1A) in the beginning, as suggested by @Daniël. I was not able to monitor the cell voltages, since the batteries are older models without bluetooth connectivity. However, when the charging voltage raised to 10V (2,5V per cell on average) I raised the current to 0,5A and at 11V to 1A.

When the charging voltage was 13V for both batteries, I connected them again in series and charged both of them with 5A current for some time with the adjustable power supply and then connected the batteries to the MultiPlus, which immediately switched back on and started charging the batteries with grid power + PV.

The batteries did not swell and I didn't observe any excess heat during the slow or fast charging.

I will continue monitoring the status of the batteries and report if something weird happens, but so far I'm optimistic, that the system functions properly again.

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Daniël Boekel (Victron Energy Staff) avatar image Daniël Boekel (Victron Energy Staff) ♦♦ commented ·

Hi @anttikan

Please do -not- connect in series before completely charging them separately or in parallel.

You have to give them time to fully balance.

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anttikan avatar image anttikan Daniël Boekel (Victron Energy Staff) ♦♦ commented ·

Ok, thanks for advice. I will disconnect the batteries again and charge individually to 100% and let them balance.

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anttikan avatar image anttikan Daniël Boekel (Victron Energy Staff) ♦♦ commented ·

My adjustable power supply can only provide 5A at maximum. Is that enough for balancing a 12,8V/90Ah battery? I read somewhere, that there's a risk of overcharging if the current is too low.

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Daniël Boekel (Victron Energy Staff) avatar image Daniël Boekel (Victron Energy Staff) ♦♦ anttikan commented ·

Hi @anttikan

lower current is better, if you don't have a BMS connected, I'd use less than 1A per battery for charging.

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