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Setting DVCC volts for LFP 16 cells battery

I have LFP 100Ah 16 cells from "XD battery" and MultiPlus 48/5000. Both connected via Cerbo GX, via VE.Can configured as BMS Can. Related configuration already done in VE Configure.

I always getting over-voltage error, as on Cerbo GX, as on battery BMS.

I started from 56V and went to 54.9V charging voltage. The last one is not enough to have 100%.

Whole process diagram:


At the point (1:12) where lowest voltage goes down, the inverter stopped charging.



Is there something wrong with BMS or/and VEConfig settings, or anything else?

Why highest voltage raises and lowest goes down after stop charging?

kirby asked
Alexandra commented ·

1 Answer

Can I dump to grid when my batteries reach a certain charge?

Say my batteries reach 90%, can I trigger a dump to grid?

Am using Home Assistant and modbus for control.

groundattack asked
Alistair Warburton answered ·

1 Answer

Tesla Batteries Overvoltage Charge


I have recently upgraded an existing solar system by adding a second MPPT Bluesolar 150/70 Tr. The original system was composed of 2 Multiplus-II and a single Bluesolar 150/70 Tr all connected to a Cerbo GX. The battery was composed of the 2 cells from Tesla.

Upon connecting the new MPPT we measured the voltages at the battery side and it was 57V but what I wasn't aware of at that time, was that these batteries could only be charged up to about 49V so I didn't find it strange to have that voltage. As the new MPPT was also connected to the Cerbo GX I wrongly assumed that the voltage from both MPPTs was being controlled by it and thus no further configuration was needed to the system.

Unfortunately the system was left like this for 2 days before we finally realizing the mistake. Upon disconnecting the battery and measuring its voltage it was at a safe level of 49V.

My question is if has this killed the batteries or do they have an internal BMS that effectively disconnects them from the 57V source causing no harm to the cells inside?

Please let me know your thoughts.

pedroply asked
jjbond edited ·

2 Answers

Orion t isolated 12/30 outputs doesn't change between different charging phases

Hello Community,

I have posted several questions here lately and the situation is getting weirder and weirder...

My last issue was that my orion stay in 'bulk' phase but input and output both on 13.5v(odd).

today while I was driving and monitoring my app - the charger did move to the other phases but...

absorption mode and float mode both had the same voltage values (input: 13.9 output: 14.2) even though the app settings clearly state the the float voltage should be 13.5v

after coming home I turned off the engine and let the system shut down (the app does say that it shut off due to engine should down), and checked the charge on my battery (my battery has a small screen that will show) - and it was 14.2v while resting.

I am really concern that I am overcharging my batteries and killing them, is my Orion faulty? please can someone shed some light on this weird behavior. thank you

I am attaching some screenshots for better observation





Mado (Mado) asked

0 Answers

Charge Voltage Setpoint

I get High Voltage Alarm from BMV, hi alarm set at 55 V. I track Charge Voltage Setpoint on VRM custom widget, 57.5 V in Bulk (battery Volts are normal), where does this setpoint come from? The High alarm seems to occur when the VE bus state changes from Bulk to Absorption, in Absorption setpoint becomes 53.5 (battery Volts settle on 53.5V), as set in VE Config, and Setpoint 51 V when in Float (Battery volts 51 V). all as per battery requirements. Max volts on battery is 55 V. Some voltage spikes are higher than 58 V. i have been trying to catch this on my fluke 187 with fast high/low V but have not managed it yet....

system is Multiplus 5 kW, 250/70 smart solar, AC coupled Fronius 4 kW, 4 Huawei 120A Li-Ion, bmv 700, CCGX.

Keith Arnold asked
Alexandra commented ·

0 Answers

Loaddump @ Protection of Smart BMS with Renogy LiFePO4 12V 200Ah


what will happen to the Mulitplus or the SmartSolar Charger, it a smart BMS of a 12V LiFePO4 Batterie ( in my case from Renogy) will enter the protection mode and open its relais? With an other Inverter and solarcharger i got a damaged inverter finally......

How is the SmartSolar Charger and the Multiplus protected against such Loaddumps ?

matthew69 asked
Paul Simon answered ·

1 Answer

Multiplus II 12/3000/120/32 charging voltage runout

Dear all please give me your lights on that matter because I cannot figure this out.

A customer of mine that is now far away from me, has problems with the absorption state of charge.

As you can see on the graph below, after a big load is turned off, or the system is reset (off-on), the absorption voltage goes up to even 14.75 and customer is reporting even 15.35 for 15 seconds causing alarms.

The ABS settings on the Multi is 14.4V and temperature voltage compensation (-16,2 by default) and is not supposed to be triggered when Battery temperature is 18C as on the example bellow. (that's not very clear to me when it triggers from the info I find).

All that happens in 3 - 4 cycles on every restart of charge and not more that a 20 seconds or so each cycle.

Anyway, I tried to change temperature compensation setting to make sure that is not the case from remote configuration, but the settings are not saved on the machine, even after turning it off/on after the setting.

I get no error message after I close the VE.config 3, I get the message and it seems to save the file properly to the device.

Cerbo is on V2.92 and Multiplus II on 500 (problem was also happening with previous version of multiplus II I think it was 496)

Do you think that I have to send him on a dealer for warranty.

The installation consists of the following:

Multiplus II 12/3000 (Battery temperature sensor connected)

MPPT 100/30

BMV-700 (this is set as systems battery monitor in cerbo)


3 GEL Exide ES1350 on 12V system




Dimitris Mavronas asked
JohnC answered ·

1 Answer

Dealing with power surges on low-current devices in stand-alone PV system

We own a property disconnected from the public power grid with a self-sufficient PV system. The other day we had big problems with our low current devices (router, house control, heating, heating control etc. all failed) and I investigated the problem. Apparently, a power-hungry device was turned on at about 9:10 on a Friday morning, so phase B was overloaded. It probably caused voltage spikes which caused power surges to the low-current devices. My investigation revealed that the culprit was a very powerful drill. Fortunately, I don't think anything is broken. The alarm messages are in the portal and everything can be traced in the log files.

My questions:

Can I protect my power grid from such power surges? How?

How else can I prevent such risks?

essi asked
wkirby answered ·

1 Answer

Cell #4 above 3,75 volts when charging from the buck boost

Hello from France (excuse my poor English, and also the long story).

In my RV (a camper van), a Victron system was installed in January 2019 by the van fitter, a pro, with the advice of a Victron technician.

The system is composed of :

  • a smart Lithium 12 volts battery 200 Ah

  • a BMS 12 200

  • a smart BMV 712

  • a MPPT smart 100/30 with 2 x 150 Wc solar panels

  • a Buck Boost 50 amps

  • a Multiplus 35 A 800 W

  • a Battery Protect 50 A.

During 3 years, everything was OK.

In May 2022, I reconnected the battery to the devices (each winter I disconnect it during several months) and I started the engine :

I observed no increase in the SOC ! Victron Connect told me ‘charge deactivated’.

So, after a few minutes, restart of the engine (I dit it several times) and Victron connect showed me that cell #4 had an increase of its voltage above 3,80 volts, sometimes above 3,9 (the current received from the buck boost was around 40 amps) when the 3 other cells stay at their initial value.

I then plugged the system into the 220 volts mains; same thing happened although the voltage of cell #4 was «only» around 3,77 volts (amps received were between 25 and 30).

When I let the system on the mains, a cycle of deactivation – activation begins and after several hours, the Multiplus was able to charge the battery, it has a 100% SOC.

When only under the sun, everything works fine, the current received from the MPPT is lower (around 15 A or less) and the battery can take the charge.

So I went on a trip with my camper van for several weeks : there was no improvement. I just noticed that the cells were very often unbalanced.

When at home (July 2022), I asked the installer to start a balance process, thinking that, maybe, it would have an effect on cell 4; they did it, with the help of a Victron technician, and finally after several days of low current charge, the cells were balanced.

But, in fact, no change, when starting the engine, the load is deactivated after few seconds.

I went again on a trip during the summer, relying on the sun, but I had to go every 2 or 3 days to a place with electricity. A pity as I am a fan of off-grid in the nature.

Remark : one day, after the engine start, it was OK, cell #4 and cell #3 had both a voltage increase but less than 3,75 (3,73 and 3,69) while the 2 other didn't move → no deactivation ! I was happy.

This phenomenon continued one day more but unfortunately not after.

The only event I can remember is that the evening before, I was off road (a poor track during some meters), there was a big hole and bump on my way and I had to manage it together with the gradient, so not very slow.... maybe the battery was shaken a bit.

I would like to know if it is possible to easily disassemble the battery, have a look on cell #4 and its connection, and perhaps, at the end, to replace it by a new cell from Victron.

Appreciate any help from the community, as the installer says : will have to replace the battery.


pittgv asked
pittgv answered ·

2 Answers

Disable voltage sens by the VE Direct

How to disable voltage sensing when MPPT and BMV712 are connected by VE Direct?

The Issue occurs when charging the aux battery only and the house battery is isolated from the charger (MPPT). The aux battery will be overcharged due to VE direct will read voltage for the house battery. Voltage sens must be disabled.

best-lithium-battery asked
Alexandra commented ·

1 Answer

Lightning current arrester for BlueSolar or SmartSolar 250V

Hello, could you recommend me a suitable combined lightning current arrester of type 1+2 for BlueSolar or SmartSolar 150V? The typical arresters of this kind, e.g. DehnCombo are rated for at least 1kV DC. And what to do with the minus pole? Are those MPPTs buck converters and minus poles of input and output are the system ground and can be earthed? Or the input must be left floating and both poles have to be protected? Thanks.

Anton asked
Anton edited ·

4 Answers

MPPT150|35 Overvoltage without solar panels conncted

Hello Victron community,

I have a problem with one of my MPPT150|35A. Eventough I disconnect the solar panels I still get an overvoltage error #33 (Error code: #33 - Input voltage too high).

My setup consists of a pylontech battery and five MPPT150|35A controlled and monitored by a Cerbo GX. Every MPPT150|35A is connected to 6 solar panels. Three in a row and two in parallel. The open circuit voltage of a single solar panel 41.14 V so 124.2 V is the max string voltage.

All MPPT150|35A work like a charm expect one MPPT. This MPPT drops the error #33 overvoltage. The max voltage in the history of the MPPT is 130V.

First thought was, that this solar panels have the longest distance to the MPPT with approx 30m and the inductivity might be a problem.. I tested other panels with shorter cables and got the same error. Today I disconnected the solar panels completely and still have the same problem.

What are your ideas?

Thank you very much!

victronthumbsup asked
victronthumbsup commented ·

2 Answers

MPPT: limits and exceeding of PV input voltage

Hi all,

even after reading through https://www.victronenergy.com/blog/2014/03/28/matching-victron-energy-solar-modules-to-the-new-mppt-charge-regulators/ and several posts here, I couldn't find an answer to my question:

Given there are two 200WP solar panels with Voc=46,6V and Vmpp=40V, connected in serial to a Smartsolar 100/30. Online MPPT calc says; it's a match. As long as you don't enter the temperature coeffients, which I'm trying to obtain since some days now by contacting manufacturer, searching online etc.

When playing around with values of -0,25% to -0,35%, the calculator jumps between Smartsolar 100/30 and 150/35.

Question: how hard is the voltage input limit really? What happens if it is exceeded by 0,1V or 1V or even 3V? Is there a tolerancy? Will it kill the MPPT or will it just shut off and be back again at normal voltage?

Thank you

christianf asked
klim8skeptic commented ·

2 Answers

Errors 2 and 29 on MPPT RS charge controller with BYD battery

Hello colleagues. We use BYD batteries in most of our installations. On some of our systems, after commissioning or adding new batteries, we get BYD high voltage notifications in the "Remote console" (screenshot 1). This is not a critical error and is not written to the "Alarm logs", but it does make our customers worry.


In reality, the battery voltage is far from the permissible maximum, and if you go to the menu of the battery itself immediately after receiving the notification, you can see that all the parameters are normal and it works fine (screenshot 2).


It's just that while the batteries are new and the cells are not balanced enough, the Victron system interprets this as a "high voltage" of the entire battery and starts to warn about it in this way. After a couple of weeks or months, these notifications stop. A similar problem is described here using Pylontech batteries as an example: https://www.victronenergy.com/live/battery_compatibility:pylontech_phantom#high_voltage_warning_or_alarm_shown_on_battery_status

But lately (and only on some new systems) we are facing more serious errors 2 and 29 on MPPT RS charge controllers. I can't figure out why this only happens on some systems even though the settings we make are the same. I know that the PV voltage at the input of the MPPT RS should not exceed 8 times the float voltage of the battery, and we are far from that limit. Firmwares on all devices in the system are updated to the latest versions, as well as Venus OS. DVCC is enabled.

On one of the systems there was error 29, I carefully checked all the settings and, not finding any deviations, left the system running in this state. As a result, this error stopped appearing after three weeks (screenshot 3).


A couple of days ago we started a new system with an RS controller and a BYD battery and I see errors 2 and 29 again (screenshot 4). When I look at the battery voltage charts in the "Advanced" section, I see perfectly normal values (screenshot 5), but when I go to the MPPT RS menu in the "Remote console" I see a very high battery voltage (screenshot 6). Where does it come from? This value conflicts with all settings. At the same time, there are no errors in the menu of the battery itself. Maybe there is some problem in communication between BYD equipment and Victron?




I understand that it is possible to limit the voltage in DVCC, but on most of our systems (with the same set of equipment and settings), there are no such problems. I don't want to do many individual settings for the same systems, it can be confusing.

I will be glad if Victron employees or installers who successfully coped with this problem answer.

romarub asked
romarub commented ·

3 Answers

What overvoltage situations on input (grid) MultiPlusII can handle ?

I understand that I would find this info in norms listed in device specification but maybe someone knows it from top of the head ? Thanks.

Mariusz Zieliński asked
sharpener answered ·

4 Answers

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