I have a Victron Multiplus II GX 48V-3000VA-35A and I noticed recently during charging the SoC jumps to 95-100% and the Victron stops charging. After a few seconds it jumps back to the “real” SoC and continues charging.
This only happens when the current was ~30 seconds 35A.
I changed the settings in the Victron to a max current of 30A, this prevents this oscillation. But ofcourse I would like a higher charge current. Anybody else seen this behavior before?
I have updated the charge current to 33A, still no oscillation seen.
@RoelofH : Off-topic: Can you please detail what registers you used in this topic to get that working. You write “Solved! Somehow I forgot to set the “switch position register”, but that alone wasn’t too clear (at least not to me) to understand what you found/did. The topic is already closed for replies, and cant sent PB’s, so try it via this way 
Or perhaps an OP/Admin can re-open that topic and move/allow my post there. Thanks!
Hi Sygnition,
“the switch position register” is a register needed in the ModBus protocol (so the sensor side), and thus not inside the Victron.
For example if you look into this picture:
https://cdn.alferez.es/wp-content/uploads/2022/07/CarloGavazziFlow-1.jpg
the middle flow diagram shows the “SwitchPos” I’m refering to as well.
Thank you. I guessed so yes, but since you emulated a Victron energy meter, it must have been specified somewhere.
Mostly I was interested in what you supplied in the Modbus protocol registers to make the Cerbo detect the device. I.e. I can add a Modbus device in Cerbo via the plus button, and set IP, port etc, but not what registers it sends or what type of device it is. So after adding, it doesnt talk at all.
So where Im after is some documentation or examples what Victron expects as minimal registers before it sees it as some sort of device. Since you said you got it working, I (and more users I guess) would like some references what you did.
Thanks!
I used an ESP8266 as processor which determines the energy used in my house and sends that data via ModBus protocol over my WiFi network.
For the ModBus I mimicked the registers of the EM24, as this is standard recognised by the Victron.
The register you can find in the datasheet of the EM24, for example see: https://www.gavazziautomation.com/fileadmin/images/PIM/OTHERSTUFF/COMPRO/EM24_E1_CP.pdf
The registers I used includs the model (EM24DINAV23XE1PFB), as well a HW + a FW version = 1E, and a dummy serial number.
And for the rest just the registers of a 3 phase system (voltages, currents, power, and Energy of each phase).
Perfect, thanks for sharing these details and the protocol! (And I now realize the EM24 isnt a Victron device at all; an earlier Google search gave this impression).
For who are interested:
And as addition: make sure you set Switch-position register 0xA100 to 0x0001.
(at least that was needed by me, to make Victron be able to readout the data)
