Power jump if MP2 switch to float mode

Hello,

I have a MP2 5000. I control the MP2 power with external software via MK2 interface.
I observe that the MP2 has a jump in power if the MP2 switch to FLOAT mode.

I watch the power with extra single phase meter (SDM120). You see in the measurement:
blue = power MP2 (> 0.0 = deliver power to grid / < 0.0 = load the battery)
red = the grid power

So the grid detects a delivery of power and the victron shows a jump. After that the MP2 shows FLOAT mode.

double check: battery voltage (16s pack):
orange big line: SOC (jumps to 100%)

2 |3000

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Alexandra ♦ commented · Apr 24 at 03:16 PM

You lost us at external software.

What causes the soc to jump? where is the reading from?

Not even sure if there is a question here?

Usually when an inverter switches to float it is a discharge down to that level. Shown by the voltage drop in cells. When do you consider your battery fully charged at the end of absorption? Most people do.

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internermitarbeiter Alexandra ♦ commented · Apr 25 at 09:54 AM

OK, here some details:

The MP2 can be controlled via MK2 interface (USB-Serial adapter). The control system can be a laptop or a rasperrry pi, the only thing you need is a program to write/read the USB serial information.
That answers the question, where comes the SOC from? --> that is trasmitted by MP2. The MP2 SOC detection is not perfet, thats why it jumps if the batterie is almost full 95.x% to 100%.

I will record the status of MP2 to get more information, wich state the MP2 enters.

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Alexandra ♦ internermitarbeiter commented · Apr 25 at 07:48 PM

It depends on if you have GX and a bms connected battery or not. The ve bus synchronises to the bms connected. (Or BMV or smart shunt soc)

If not it tries to calculate itself based on parameters entered into the battery monitor section of the inverter (understandable that is can be off as there is no shunt measurement there)

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