Using BMV-712 to measure SOC of series connected batteries which are charged INDIVIDUALLY.

I am planning to use a BMV-712 to monitor the SOC of two Battle Born 12-volt Li batteries connected in series to run a 24-volt trolling motor. The batteries are charged individually by 12-volt chargers.

I can find multiple diagrams for using a BMV-712 to monitor:

12-volt batteries wired in parallel, and charged separately,

6 volts in series to make 12 volts and charged with one 12-volt charger.

6 volts in series to make 12 volts, with several connected in parallel to increase capacity.

This is what I have in my travel trailer, which is charged through the trailer system, or can be switched to be charged by a Sterling 60-amp battery to battery charger I can connect to the truck with an Anderson connector. This is monitored with BVB 712.

What I do not find is how to use one (or two) BMV-712’s to monitor series connected batteries being charged individually.

My thinking is this:

I have 12-volt batteries A and B connected in series to yield 24 volts.

Both batteries A and B are charged individually.

Connecting to measure both batteries:

If I connect the BMV shunt between the negative terminal of battery A and the trolling motor, the shunt will detect the energy supplied to the trolling motor by BOTH battery A and B, but will only detect the energy charging battery A. With each use and charge, the calculation of the SOC will be off by 50%. The only ways I can think of to compensate for this is to adjust the peukert exponent to be about .52, or the charging efficiency factor to about 200%. The ranges shown in the manual do not include these drastic settings so I doubt either is possible.

Connecting to measure ONE battery of the pair.

If I connect the BMV between battery A and B the shunt measures the current flowing from battery B to battery A. When charging, the shunt will measure the energy used to charge battery B. The SOC should be accurate for battery B. Batteries A and B are “matched” per Battle Born- and under the same load from the trolling motor, so the SOC of A should be very close to battery B.

Is there a way to measure the SOC of both batteries?

Is there a better way to measure the SOC of one of the batteries?

The rest of the story:

I have two Battle Born 12-volt 100 AH Li batteries connected in series to produce 24 volts to run a trolling motor. The batteries are charged individually by two different systems. The primary means of charging is a Dual Pro charger (15 amp per battery) The batteries will also be charged by a Minn Kota MK-2-DC onboard alternator charger. Its output is up to 10 amps per bank with a 25-amp alternator, but my outboard only puts out 20 amps.

It would have been simpler to have two 24-volt Li batteries in parallel charged by 24-volt chargers- but that is not what I have…

hednout asked
Kevin Windrem answered ·

1 Answer

Victron Connect blocked access to SmartSolar settings

With Victron Connect v 5.41, something very surprising happened yesterday. When I tried to see what my MMPTs were doing, I noticed a warning marker over the settings icon and when I clicked, I was told that my access to either view or edit my MMPT settings was blocked - unless I performed a firmware update. Is this correct - I haven't seen that before with VC.

ian273 asked
Guy Stewart (Victron Community Manager) commented ·

3 Answers

Lynx Shunt VE.Can mV values

What are the Amps -> mV values for the Lynx Shunt VE.Can 1000?

rspott asked

0 Answers

How much data is transmitted between a CCGX and the Portal

I have a remote solar installation which I monitor through the Portal, and use a sim card in a router for the connection. However I do not understand the data patterns and sizes which my service provider says I use. There is nothing else connected.

There is a connection made every eight hours between the sim card and presumably the Portal, which use around 1MB. Then there are occasionally bursts of about 3Mb each, usually occurring in groups of four. Roughly this happens about once a month.

Can anyone put an activity to the communication please? Are the large bursts (totalling 12Mb each occasion) me accessing the portal/CCGX? I need to understand the data usage to get an appropriate mobile communication package

ianwhite16 asked
ianwhite16 commented ·

1 Answer

VRM Verification E-mail Not Received ?

Hi All,

I have not received the verification email to complete my registration for VRM and there is no option to resend it. Could someone please assist ?

byron asked
Teun Lassche (Victron Energy Staff) commented ·

2 Answers

Error Message: 'Incompatible VEBus configuration' Error: mk2vsc-61

I commissioned a 135kVA (9 x 15kVA) system on Friday and am trying to adjust settings but getting this error when trying to download configuration:


I see there is something in Gitmemory about this being an issue > 6 units but it seems solved:

warwick asked

0 Answers

Quattro Low Battery Alarm/Warning during engine start

Victron enthausiats,

Almost every time I start the main engine of my boat, I get an alarm or warning for Low Battery, sometimes also for DC ripple.
I hoped the newest version of the Quattro firmware would solve these very short "disruptions'.
Can these be solved by a setting?

harold asked

0 Answers

Voltage for ground relay information wrong in manual ?

I have a Multiplus 24/5000/240 and an Autotransformer. According to the Autotransformer manual the Relay is 12 V, and the output voltage of the Multiplus/Quattro is also 12V regardless of the DC Voltage of the Inverter. Here is what it says in the manual

When the Internal ground relay is not selected in VE Config or Victron Connect, there is 12V on the external terminal of the Multi/Quattro for the ground relay control (on all models 12/24/48V this voltage is 12V).

However if I measure the voltage I get the DC Voltage of my system (in my case 27V) and not 12V. I am afraid this will burn out the coils on the Ground Relay in the Autotransformer.

mfriedel asked
mfriedel answered ·

2 Answers

VRM Dashboard new thing " Time To Go " under Battery section ? , appeared and vanished




Just noticed this today , appeared and disappeared within a minute.

Anyone know what that is relating to ?

Work in progress?

I am guessing time to go Batteries to full charge at current charge state ( when they are charging ) and Time to go before batteries fully depleat at current discharge state?

teloth asked
harold commented ·

0 Answers

Current limit display won’t turn off on Digital Multi Control

I have a DCM connected to a Multiplus 12/3000/120. I also have a VE Bus BMS and an Octo GX. Recently I installed a VE Bus Smart Dongle and although the Multiplus seems to operate correctly when I turn the DCM switch to Off all the lights go out except for the numeric current limit display, this now stays illuminated in all three DCM switch positions. How can I restore the DCM to normal operations?

Tim Chapman asked
1point3liter edited ·

3 Answers

Orion-Tr Smart, VE.Direct and integration with GX devices?

Hey there, as I commented on the blog post,

"I'm curious if future versions will have VE.Direct or some sort of integration like that with GX devices? Currently, it seems that the MPPT and MultiPlus are able to coordinate their total charge rate with external BMS via the GX devices. But it seems that the Orion-Tr does not participate in this?"

I'm wondering if there's a way to integrate the Orion-Tr Smart chargers with the CCGX. In particular, as far as I understand, GX devices can coordinate with external BMS via CANBus to determine the charging parameters of a battery. It seems that the Victron MPPT and Victron MultiPlus can respect these limits via VE.Direct and VE.Bus respectively, which is great and a big reason why I bought this BMS and the suite of Victron product.

Now I'm considering purchasing Orion-Tr Smart chargers, however I noticed that they don't have any VE.Direct connectivity, or any other VE connectivity aside from the Bluetooth one. Is something like VE.Direct, VE.Bus or VE.Can planned? Will Orion-Tr Smart chargers integrate with GX devices?

aybabtme asked
cwoody answered ·

12 Answers

MPPT 250/100 Tr Maximum 390W panels

Obviously a newby here, I have 28 390 W Canadian solar panels and would like to know if I can connect them to my smart solar MPPT 250/100 in 7 strings of 4 connected in series.

The Isc is 10.17 A

Voc 48,2 V

Hannes Swart asked
JohnC commented ·

2 Answers

2x MPPT 250/100 not producing expected output

I now have 2 x 250/100 MPPT's that I have connected 28 x 390W panels 4 in series and 7 strings, 4 strings to one and 3 to the other. My question is why at peak hours am I only producing 6500W?

I have a Freedom Won 30/24 LifePO4 battery connected as well as a generator on remote start


Hannes Swart asked

0 Answers

Phoenix inverter zero load negative value

My 24/1200 inverter shows an output current value of -0.7A in VRM. I know that the device is not accurate but that 160W fault throws the DC draw way off. If I turn of “Has DC system” in Venus OS on my pi I loose the numbers for Consumption in VRM so that isn’t a way I want to go. Would it be possible to specify a fixed offset in VRM to correct the imprecise measurement of the inverter? So that -0.7A is 0 and 0 is +0.7A? That would at least get rid of the major error whenever the inverter isn’t supplying any current.

System: SmartSolar 100/20, SmartShunt, Phoenix 24/1200. All connected with VE.Direct-USB cables to a Raspberry Pi Venus OS.



jh8001 asked

0 Answers

Split phase with two 120v Quattros and 5500 onan genset 30 amp each leg in an Rv configuration

I have two quattros I am going to setup as primary and Secondary/slave. I believe my 5500 watt onan is split phase 180 degrees out for 120/240.

Do I need a transfer switch if the genset is connected to ac-1 input on both quattros?

I would like to wire the quattros with each leg from genset to each Quattro along with each leg from shore power to each Quattro.

just want to make sure the transfer switches in the quattros can handle the transfer between shore and genset without an external transfer switch…

thx for any input

Geoffrey Schwark asked
Geoffrey Schwark answered ·

2 Answers

Which Victron MPPT Settings for AGM battery?


I have just installed new Victron gear and im not sure what settings i should have for everything.

I have the Smart Shunt, Mppt 100/30 controller, Dc12/12/30 charger and the IP22 12/30 chager 3 ports.

I have 2 Ritar 120 AH AGM bateries connected for a 240AH total.

Which profile should i select for these batteries and are there any other settings i should change?


destrvction asked
destrvction commented ·

1 Answer

MPPT RS case interferes with the VE.Direct connector

I am using a Victron VE.Direct cable with my MPPT RS 450/100. The position of the MPPT case means that the cable plug won't fully seat home in the socket of the MPPT. More than once it has not made a connection between my MultiPlus II GX and the MPPT. This seems like a design flaw and could be rectified by making up my own cable rather than using the Victron cable. Alternatively I could cut away some of the case but would rather not do this. Any advice?



paulcooper asked
Ingo commented ·

0 Answers

Venus Docker Grafana 64-bit Images

Good day

I have a 64-bit Raspberry Pi 4 with an Ubuntu operating system on which I have installed a 64-bit Docker system.

Now I am wondering if anyone can help me to find the venus-docker-server, venus-docker-grafana and venus-docker-upnp images that I can use, if such images are available.


bertie-bezuidenhout asked

0 Answers

PV-Eingang MPPT 75/15 über 2 poligen Umschalter wahlweise mit Solarpanel und Dauerstrom des Zugfahrzeugs verbinden

PV-Eingang MPPT 75/15 im Wohnwagen über 2 poligen Umschalter wahlweise mit Solarpanel und Dauerstrom des Zugfahrzeugs verbinden, geht das? Der Hintergrund ist der, das ich während der Fahrt den Bordakku des Wohnwagens aufladen möchte, Die 12V Versorgung des Wohnwagens würde dann (außer Kühlschrank) komplett über den Lastausgang des MPPT laufen (nur Innenbeleuchtung und Wasserpumpen für WC und Waschbecken).Benötige ich für diesen Zweck einen zusätzlichen Booster um die ankommende Spannung zu erhöhen, bzw, ein zusätzliches Ladegerät? Als Bordbatterie plane ich eine LiFePO4 Lithiumbatterie einzubauen

Hat jemand schon eine kleine Autark-Lösung für Wohnwagen realisiert. Im Wohnwagen ist eine Schaudt CSV300 installiert, Ich möchte nicht die Schaudt CSV409 einbauen.

Mit freundlichem Gruß

Wilfried Wendland

ballonwilli asked

0 Answers

smartsolar 100/20 load switches off in float mode

I have noted several people have problems with load switching off eg fridge.

So am testing with a simple halogen lamp which draws 4.5amps. The lamp will stay on in bulk and absorb mode but turns off in float mode. It works fine with no pv panel at all (draws power from battery through reg) but will not turn on in float mode when pv is connected??

Is this a software fault, I am using f/w v1.37

ray-pridham asked
bazbrush edited ·

11 Answers

Difficulty with MPPT100/30 + 305W solar

Hi there,

I got a Victron 305W Solar panel and smart solar MPPT 100/30 installed by a mechanic in my van but I feel like it's not working appropriately.

The Mppt is connected directly to the batteries (2x100Amp in series) (positive on first battery, negative on second). Theres a fuse breaker between mppt and batteries.

My problem is that the app always shows float, no matter how much I've used my fridge, lights etc. It also shows immediately whatever voltage I put in the battery settings. So If I change the battery voltage to 14.0 it just jumps to it without ever entering "bulk" mode. Lastly my wall voltmeter (I know it's not fully accurate) keeps dropping during the day and night.

Not sure if it's important but I also have a split charge relay to charge the batteries while running the engine. So when I drive for a while and stop my wall voltmeter shows 12.8V while the victron app doesn't show a higher voltage. When the engine is running the app is jumping all over the place showing battery voltages between 4 and 15 and going between float, bulk and absorption.

I would really appreciate any help.

Thank you in advance.




iris123 asked
iris123 answered ·

2 Answers

BlueSolar 100/50 mppt controller shows "State" as "Off"

I connected the BlueSolar 100/50 mppt solar controller to my solar panel and battery. The bluetooth app shows the battery "state" to "off" and the "virtual load output" to "off". There is an information icon above it that says "why is this charger off?". I click on that and nothing happens.

Best I can tell is the solar charger never turns on as it always shows 0 watts from the solar power. when I test the solar panel though it shows 32 volts coming out of the wires just fine from my multi-meter.

codydog asked
jperez (Victron Energy Staff) answered ·

1 Answer

Victron/Mastervolt compatibility

We have a Lagoon 39, which was originally outfitted with Mastervolt Mastershunt 500 to monitor the batteries. I purchased a Victron inverter/charger along with a Cerbo GX for monitoring all electrical currents. Question: Can the Cerbo GX use/read the existing mastershunt 500 to monitor battery levels?

tilapia asked
gro edited ·

3 Answers

Possible to monitor multiple inverters with one cerbo

Setup is 2x Phoenix 24/3000/120 vebus stacked. I Plan on adding either a Phoenix 24/3000/230 or a multiplus to handle my 230v equipment. Question is, Will one cerbo gx recognize and show the separate units?

trwr321 asked
gro edited ·

1 Answer

IP22 - Lead from charger to battery


I was recently gifted a VICTRON Blue Smart Battery Charger 12V 30A IP22 (3) Outputs to replace an old Euro style charger for my caravan.

Unfortunately, the gift did not include a lead to connect from the Charger screw terminal (AwG6) to my battery. I would prefer a lead without clamps.

All I can seem to find is IP65 accessories.

What lead do I need to go from the IP22 to the battery?

caittravels asked

0 Answers

MK3 ok with victronconnect but not ve config

With two installers at site, two laptops, two MK3's (both with moulded in cables) both can connect to the Mulitplus-II GX with VictronConnect. But when they close VictronConnect and open VE Config (to set up PV Support assistant) they cant connect. They get 'Help on Connection' notification, etc, Have tried downloading drivers, running Prolific_DriverInstaller , etc etc but no change. (have also tried setting up via VRM but limited connection at site)

Any thoughts?

David asked
Guy Stewart (Victron Community Manager) answered ·

1 Answer

Ve.bus BMS and Multiplus in Passthru

On a boat installation, I have an existing 3k/12/120 Multiplus (current firmware) and have just swapped out AGM batteries for Victron LFP batteries and added a ve.bus BMS plus a Cyrix Li-ct.

BMS assistant installed in Multiplus.

At first startup, I am getting a low battery led on the Multi, even though voltage across the multi's battery terminal shows 14.5, and the Multi is stuck in Passthru mode.

No charging and no inverting functions.

The BMS V+ voltage is 14.6, but the Load Disconnect and Charge Disconnect outputs are low, 0V.

Is it possible the BMS is defective? How would I bench test the BMS.

There was a Cerbo in the system, but it is disconnected at the moment.

Victron Connect thru the MK/USB interface shows everything normal in the Multiplus.

jerrykeefe asked

0 Answers

Your Experience with Warranty Claims

What exactly is the warranty when you buy Victron products? Is there a link to "the fine print"?

Has anyone had to claim a warranty for a component that stopped working? If so, how was the process. Did you have to ship the component somewhere? Who paid for that?

agroventuresperu asked
Vance Mitchell edited ·

4 Answers