Ess on multiplus2 gx not going back to bulk charge

DIY
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1

I have a multiplus 2 4k5 gx and 3 x Deye SE-G5.1 Pro-B - 51.2V 5.12kWh i use a vm-3p75ct meter

                3-fase NET

                    │

             VM-3P75CT  -- meter

                    │

      ┌─────────────┴─────────────┐

      │                           │

    HUIS                    MultiPlus-II 4K5 GX

                                 │

           ┌─────────────────────┼─────────────────────┐

           │                     │                     │

       Batterij             AC-Out 1             AC-Out 2

                           Garage + AC-PV         BTC Miner relais

the battery manager is on auto and it is the mp2 I am running ess optimized without battery life.

every morning it doesn’t wat to charge well. it stays in float or in absorbtion if it wasn’t filled to 100 soc the day before.

only when I reboot the mp it will start charging in bulk mode right away.

It seems like the victron doesn’t know there is a surplus. the state isn’t changing back to bulk.

I have noticed that the ac loads on the right side of venus is a bogus number. it takes l1 and l2 and adds l3, even if that is a negative number, meaning we are exporting to grid, can be either trough pv or by discharging the batt. so i think it might be that the mp2 doesn’t see a surplus as it counts it as loads ??!

any help would be greatly appreciated !!

2

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Screenshot 2026-07-16 0914401513×802 84 KB

3

Your phases dont seem to match between grid and load. L3 on the grid side seems to be L1 on the load side.

For me my MP2 is also not installed on mains L1, so i simply cycled the CTs of the gridmeter over, so that the same phase that the gridmeter measures as L1 is also physically connected to the MP2.

How does your AC PV report its power output to the Victron system?

Did you set your ESS to compensate all phases? What gridsetpoint is set?

4

hey chrigu, I thought about doing the ct switch but haven’t done that yet. so yes it is physically on l3. I might try that.

my pv is connected on acout but has no particular communication with the victron, i have a solis inverter, among others ..

I set ess to compensate all phases and the setpoint is changing by my python script but can be seen as zero. this “'bug”" comes with or without script.

5

But the ESS needs to know the power output of the AC PV in some way

6

I hope not. I have several different small and less small inverters. It should just sense or read grid meter. Tomorrow I will change the l1 and l3 ct and voltage sense wire on the meter.

had to laugh about this sentence A USB GPS can be used to enable remote tracking of vehicles or boats via the VRM Portal. wasn’t planning on following my gf with my victron but hey who knows.

what I read on your link " Note: These measurements are for monitoring purposes only and are not required for system operation or performance."
the thing is when i reboot it will bulk charge. but only after i reboot.

7

does anyone know how ess would decide to go from float to absorption to bulk charge ?? my system charges in bulk till a point then moves to absorption but it never goes back to bulk until reboot. then it will bulk charge on excess ac coupled pv.

the system never raise the allow charge voltage

from:

60.79999 oid to

root@nanopi:~# dbus -y com.victronenergy.vebus.ttyS3 /Hub/ChargeVoltage GetValue
value = 56.79999923706055

but not back. what parameters or variables need to click for this to go back to bulk ???

8

sorry for the bump,

has anyone an answer on how or why will ess normally decide to go from absorption or float back into bulk charging ??

From this:

dbus -y com.victronenergy.vebus.ttyS3 /Hub/ChargeVoltage GetValue
value = 60.79999923706055

to this:

Why does the charger state machine sometimes decide that 56.8 V (Absorption) is still appropriate, but then after a MultiPlus restart—it immediately decides on 60.8 V (Bulk)?

9

Bulk phase is constant current phase, so theres no voltage directly related to that. The battery is charged at whatever the charge current is set to be. I guess the raise to 60.8V is just a way for the system to “deactivate” a voltage limit. But i havent closely inspected what the system does in dbus.

Until the absorption voltage is reached, then that voltage is held stable, constant voltage mode.

Since you are using Deye LiFePos, its the BMS that decides on the CVL, charge voltage limit, which through DVCC then regulates the Multiplus output.

10

thanks for your input. It seems to work now. I’m not sure if it was placing the ct on l1 at the meter or one change i made in veconfig the float voltage was somehow set to 52.8 and it is now set to 54 volts. Idk it seems to work now. if I don’t come back here then i am a satisfied customer :wink: