question

hardy-tuner avatar image
hardy-tuner asked

ESS with VE.Bus BMS overvoltage with PV Inverter at ac out

ESS Multiplus with VE.Bus BMS overcharging Battery because ignoring voltage settings. AC in was off, PV-inverter at AC out was plugged in. In livedata you can see that mppt was stop charging, but Multiplus was still going on.

Is this happen because Multiplus can't stop the PV Inverter?

Why VE.Bus BMS doesn't shut down Mulitplus?


- Multiplus 12/1600 FW490 (max charging Voltage 14,14)

- VE.Bus BMS

- Victron 12V 200Ah (recommended stop charging Voltage 14,2)

- ET340 at ACout

- PV Inverter EVT300

- MPPT 75/15 (max charging Voltage 14,10)

- BMV712

- EM24 Ethernet (Grid)


overview.jpgImage Caption

live-data.jpg


mppt.png

multi.jpg

battery.png


MultiPlus Quattro Inverter Chargermultiplus ve.busVE.Busovervoltage
overview.jpg (225.0 KiB)
live-data.jpg (237.5 KiB)
mppt.png (161.9 KiB)
multi.jpg (103.4 KiB)
battery.png (122.8 KiB)
1 comment
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Alexandra avatar image Alexandra ♦ commented ·
@hardy tuner

I would hazard a guess and say, yes it is because the system would normally control the PV inverter but in this case it cannot. So if you are not feeding back to the grid, the power would need to be absorbed by something.

The PV inverter is obviously not ramping down here.

See about setting up a way for the inverter or pi or something to switch off the EVT300 when SOC gets higher.

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2 Answers
Matthias Lange - DE avatar image
Matthias Lange - DE answered ·

Is the PV Inverter assistant installed on the MultiPlus?
https://www.victronenergy.com/live/assistants:pv-inverter-support

If the assistant is installed and the PV-inverter is not shutting down than you are not allowed to connect that PV-inverter at the output of the MultiPlus, you have to connect it to the input side.

14,2V is not the cut-off voltage for charging. The range for charging is 14-14,4V and the recommended absorption voltage is 14,2V.
So you should set all your chargers to that value, just select the lithium preset.

If I'm correct the "stop charging" signal is coming at more then 3,75V at one cell (15V).

Oh and BTW, your MultiPlus is not certified to be used in an ESS!

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Meine_Energiewende avatar image
Meine_Energiewende answered ·

Sieht mir schwer -> wie Herr Lange schon sagte <- nach einem nicht oder falsch konfigurierten PV Inverter Assistenten aus.

Gruß

Jens

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