VE.Bus Image


VE.Bus BMS verses smallBMS and signalling charge disconnect to MPPT controllers

As I continue to investigate the possible connection options to get my system working as I require and following on from my question about VE.Bus BMS verses smallBMS. I hope someone can help with this part of the communication flow and if any functionality is lost be using a smallBMS verses a VE.Bus BMS.

I am aware that the Cerbo is able to signal via VE.Direct or VE.Can to connected Smart MPPTs that a charge disconnect event has happened. This is confirmed in this post where Guy has stated "Yes, it works. The VE.Bus BMS will signal to the Multi on the VE.Bus, and then that will be sent to the GX device which will control the MPPTs via or VE.Can (>2019 models only) cables."

However there is nothing about the smallBMS. The above post has a link to another post where Matthijs says "Regarding connecting: the Venus GX cant retrieve data directly from the VE.Bus BMS. So, even though they are on the same network (VE.Bus); you still need an inverter/charger in that same network to make it work.". This implies to me that the MultiPlus sends the charge / load disconnect to the Cerbo and not the VE.Bus BMS itself.

While I have a VE.Bus BMS at present it is not connected to the VE.Bus and I am using a 2-wire assistant on my Multiplus. The Cerbo shows this and when the pin on the VE.Bus BMS goes high, the Cerbo state changes too yes. So I know the Cerbo is getting the information.


So the details are getting to the Cerbo. Therefore with a smallBMS or VE.Bus BMS using 2-wire assistant, will the MPPTs still get a charge disconnect via VE.Direct or VE.Can. I am unable to test at the moment as while my MPPTs are installed the Solar panels are not yet installed.

I would like to know if when using the smallBMS, the VenusOS will still signal charge disconnect to the MPPTs, and how I can tell if the signal is getting through to the MPPTs. For info I have two VE.CVan 150/70's connected via VE.Can.

bathnm asked

0 Answers

DMC needed with Cerbo GX, Gx Touch 50 with Multiplus 12/2000???

As the title says, everytime i chop and change my equipment selections for my upcoming RV build, im presented with more confusing aspects.

Do i need the DMC with the above mentioned components if im using a VE.Bus BMS or has that been removed now? Can i control the Charger only/On/Off portions with the GX Touch 50 or will i be required to install another component, that being the DMC???

System will also have MPPT, smartshunt, 2/3 x lifepo4, smart battery protect

brent1982 asked
bathnm commented ·

2 Answers

MultiPlus Not Showing Live On CCGX

Good morning chaps,

I am just after a bit of help/advise. I have just finished installing a Victron Multiplus in a motorhome conversion. It is installed alongside a 70a MPPT solar controller and all are wired to a CCGX. I recently upgraded the firmware in the CCGX as the multiplus and ccgx were previously in a household setup and they have been stored over a year since I purchased them used.

The MPPT shows in the CCGX via the VE Direct cable and that shows fine, showing the solar input, battery voltage etc.

The issue is that the CCGX does not show when the Multiplus is turned on, it shows a symbol for a Multiplus but it always shows off, even when the inverter is on and powering appliances. The Multiplus is connected using one of the blue bus cables to the VE BUS input on the back of the CCGX and I have tried it plugged in to both connectors in the Multiplus but nothing shows up as working. The Multiplus also and has a temp sensor that is connected from the Sensor connection in the Multiplus to the negative terminal of my battery bank (this all came as a used setup kit other than the mppt).

Should it be a case of just plugging in the blue network cable in both the Multiplus and CCGX and it should all display as connected and working? I presume I am correct with the temp to the negative?

The setup and install is pretty much complete, I just want the Multiplus to show on the CCGX as everything is getting boxed in very soon so wouldn't want to have to rip everything out to change a cable etc....

Attached is a pic of the CCGX, I can take more pics of the back and cabling if required.


Can anyone help out here with some info or advise to get the Multiplus showing on the CCGX?

camperconversion asked
brians answered ·

7 Answers

Venus OS and VE.Bus Error Report

My system is constructed of 4 x 12.8/200Ah Lithium batteries configured as 2S2P with a VE.Bus BMS and Multiplus 24/3000/70-50 all monitored through a Cerbo..

I had an issue the other day that caused a charge disconnect event to happen, but have no traceability of this within the Cerbo alarms or Venus OS.

All I can find is the following within the Inverter menu on the Cerbo, but no detail. Is anyone able to let me know what VE.Bus Error 8/11 Report in the Cerbo actually mean.




bathnm asked
Guy Stewart (Victron Community Manager) commented ·

3 Answers

What Alerts does one get from a VE.Bus BMS connected too Cerbo

I am after some information on control signals and information flow with the VE.Bus BMS environment.

I have read the following post and done my own testing

This has highlighted that the MultiPlus/Quatro is key to the interworking. While the Venus OS, Multiplus/Quatro and VE.Bus BMS are all connected on a single VE.Bus BMS there is dose not seem to be any information that flows directly between the VE.Bus BMS and Venus. It all flows through the MultiPlus/Quatro. Therefore it is the Multiplus/Qutro that is reacting to messages from VE.Bus BMS and passing information onto the Venus OS. The Venus OS is then able to pass information to VE.Direct or CAN.Bus connected MPPT controllers to disable charge.

What I would like to know is what functionality if any is lost or gained from using a MiniBMS or VE.Bus BMS with the 2-Wire Assistant verses using a VE.Bus BMS with the VE.Bus Assistant. I know the outcome of both approaches will be that the Multiplus/Quatro will be told by the BMS to stop charging or inverting, but what else is going on behind the scenes that would make having the load/charge disconnect on the VE.Bus?

Many Thanks

bathnm asked

0 Answers

RJ45 Wires used by VE.Bus? pin out?

are all 8 wires of the RJ45 used for VE.Bus?
If not what is the pin out?

A costumer asked me that today because he thinks he have a damaged wire in his installation.
The wire is under ground and can't be changed, so he asked me if he can try figure out what wires are still good and use this wires for the VE.Bus.

Matthias Lange - DE asked
Matthias Lange - DE commented ·

1 Answer

Can I use the temperature information that is shown by my Smart Lithium Batteries in a VE-Network (Cerbo)?

Hi all!

I installed two brand-new 200ah 12V Lithium Smart Batteries from Victron in my van. Those new one come with Bluetooth connection. Via the Victron smartphone app, I can check the temperature of each battery. Now I was wondering if it is possible to provide this information to my Cerbo GX or Smart MPPT. I know that the Cerbo has several temperature sensor inputs for cable sensors. But hopefully, there is a way to use the information that is already there :)

Any suggestions? :)

tschoeki asked
tschoeki commented ·

1 Answer

VE.Bus BMS and MultiPlus / Cerbo combination

I have wanted to be able to control the Multiplus via the Cerbo, but the VE.Bus BMS and VE.Bus BMS Assistant on the Multiplus block the Cerbo from changing the invert state between On / Off / Invert Only / Charge Only.

Having done some testing I have reverted to the 2-Wire BMS assistant on the Multiplus and wired the VE.Bus BMS Charge Disconnect to the Aux 1 port and Pre-Alarm to Aux 2, using an Inverting remote on-off cable. I am now able to change the status of the Multiplus from within the Cerbo Screens. The Cerbo correctly shows the VE.Bus BMS status through the relevant MultiPlus screen. Both disconnected at the moment.


I also had a VE.Bus Smart Dongle and found I could modify the status of the Multiplus via my phone as well. When status changed the Cerbo reflected that changed status. So I have a system working as I would like, but not using any functionality of the VE.Bus. I guess I could have achieved the same thing using the smallBMS with pre-alarm.

What I was wondering is if anyone can advise what functionality I might have lost by disconnecting the VE.Bus BMS from the VE.Bus?

I have noticed during my testing today that there is no Alarm or Error that is logged when the VE.Bus BMS signals load or charge disconnect, simulated by disconnecting the signal. The Cerbo clearly isn't triggering on the change of the Multiplus VE.Bus BMS status. I am not sure if it ever did alarm/alert when the VE.Bus BMS was connected via the VE.Bus port to know if I lost functionality. I do know a few weeks back I had a VE.Bus BMS Charge disconnect event and never saw anything on the Cerbo.

Hope people find this useful and it would be good to understand what functionality has been lost by taking this approach and not have the VE.Bus BMS communicating on the bus.

bathnm asked

0 Answers

Ve bus error 1 cause system shutdown or not

If one inverter of 15 *10 k three phase system shutdown and error 1 appear. Is it cause shutting down for all system or not?

abdallah-salamah asked
Alexandra answered ·

1 Answer

On the Skylla IP44, what is parameter 31 ("BMS present") for?

Why do you need this parameter?

It implies that one can connect the Skylla IP44 to a VE.bus BMS, but is that correct?

If possible, how would you connect it as the Skylla IP44 doesn't have VE.Bus connections and the BMS doesn't have any VE.Can connections?

s-v-simbora asked

0 Answers

Is the VE.Bus BMS compatible with a Phoenix Combi 12/1600/75

I'm looking at upgrading our boats electrical system to a LiFePO4-based system. As far as the components go, I'm pretty sure I have the configuration figured out. The only thing I cannot determine, is whether our current Victron Phoenix Combi 12/1600/75 Inverter/Charger is compatible with the VE.Bus BMS. The setup I am thinking about is very similar to the example given in the VE.Bus BMS manual, shown below. Can we use our Phoenix Combi in this setup?


richard-blaauw asked
richard-blaauw commented ·

2 Answers

Networking Phoenix inverter & Multiplus Inverter/Charger


First, I'm on a boat with a dual voltage setup. We have American AirCon (120v) and Euro Appliance (230V). I have a Multiplus 12/3000/120 Inverter Charger that supplies the 120v, and a Phoenix Inverter that supplies the 230V. The Phoenix inverter has a remote switch and the Multiplus is operated by a MultiControl unit.

Can anyone see any reason to network these together? They both pull from the same 12v lithium battery bank?

Thanks for the info!


mimzy asked

0 Answers

VEConnect not showing my all inverters

What could be the reason that VEConnect is not finding all the inverters connected to VE bus?

I have 2 MultiPlus-II and 1 EasySolar-II.

I am trying to set up 3-phase system.

When I turn all of them on, and open the VEConnect, there is only 1 MultiPlus-II on the list.

When I turn on only EasySolar-II there is also one MultiPlus-II on the list. Should there be a EasySolar-II on the list when only it is on?

I also have a error #25 "Firmware incompatibility".

Apparently EasySolar-II has different firmware than 2 other MP-II.

When I click on this "error #25", I am getting message "Fetching data" and there is no end to waiting for this "fetching" to finish.

How shuld I go about making all firmware the same, so I can start setting this system up?

marekp asked
marekp commented ·

1 Answer

Multiplus VE Bus voltage step change behavior

When observing the slow decline of battery overnight with charger off one sees a step change in voltage 'VE BUS " which is not seen on the BMV 702 monitor . Its not because quantising is large as there are indeed 0.01V steps in the data. See comparison. ( Multiplus 1 - 5kVA vs BMV 702 ) . What is the cause of this?


merlepeter asked
Paul B answered ·

1 Answer

Functional purpose of voltage sense wires?

Can someone shed some light on the intended functional purpose of the Voltage Sense wires on a Multi/Quattro?

Are you using it? If so, how/why?

The manual says loosely that it's "to make up for voltage losses across the wires".

With the volt sense wires connected or not connected, under minimal load or loads in excess of 100A, I've never seen any change in the reported voltage by the system.

This was true even before my installation of a BMV (with the lithium batts) and still so now, since SOC and voltage readings (I assume) are now coming exclusively from the BMV.

The voltage reported (by the BMV) is within .01 V of the voltage reported by the BMS on the batteries with minimal load, and within the expected 2-3% difference under heavy loads.

I'm using 2/0 (70ish mm cross section) wires and runs are around 10-13 ft to the batteries. The BMV is 5-7 ft to the shunt. 24V lithium system.

The lead-acid system prior was considerably sloppier, although still using 2/0 cable, and I still recall no differences.

geomz asked
rjoustra answered ·

3 Answers

VE Bus and MultiPlus On/Off question

I just recently installed a VE Bus for the Bluetooth capability. My question is do you keep the MultiPlus always in the ON position to utilize the on/off feature in the app? Or can you have it in the off position and do the same control from the app?



mccluretj asked
mccluretj answered ·

2 Answers

VE Bus State not showing Correct Information in VRM

This is the first time I have seen this, but things don't add up on my VRM.

Earlier on today I saw that my system was using the power assist feature but upon closer inspection, the current coming from the battery was zero. But the output power was higher than the input power (as one would see during Power assist operation)- See image 1.

This happened twice more this morning, until there was a larger power assistance instance, but this time the VE.Bus state didn't show it went into power assist mode, but you can easily see that the battery was adding power to the system- See image 2.

For reference, the whole mornings data is shown in Image 3.

Has anyone else experienced this? or is this a known issue?

Regards Ewald


Image 1.


Image 2.


Image 3

ewalderasmus asked
Alexandra commented ·

0 Answers

Serial interface of Victron Phoenix Combi

Is there someone that share information on the serial interface of Victron Phoenix Combi units, besides what can be found in the manual? (screenshots below). Is this serial bus the same as VE.Bus? Are there any of the Victron accessories, such as for example the VE.BUS to NMEA2000 adapter, that can be connected to this bus?



Tobias asked
Tobias answered ·

1 Answer

VE.Bus low battery alarm, why?

I am getting Low Battery warning at a voltage that is different than configured in the settings. The pre-alarm is set to 10.9V, the ESS assistant is configured to do a cut-off at 12V@0.005C, yet, I am getting alarms when voltage drops below 12.25V at a much higher discharge rate. The battery monitor Voltage reading = VE.Bus DC Voltage reading so it doesn't look like a cabling issue.

What am I missing?

I am using VE.Bus firmware 465.






wrietveld asked
leslieanne answered ·

3 Answers

Smart Lithium, VE.Bus and IP22 Charger

I've been told by my distributor that I don't need a relay to cut off the charger in the event of low temperature because the battery will do this automatically. All the schematics I've seen show a separate relay switched by charger disconnect.

Is the distributor correct?

ragerty asked
wkirby answered ·

1 Answer

Victron Connect and Venus to get access to MultiPlus


I have a BMV712, MPPT all connected via VE Direct to Rpi with VenusOS.

I have also connected via a USB MK3 cable a Multiplus which is plugged into the Rpi.

If I then use Victron Connect App to connect to the wireless of the RPi on Venus OS it can detect the BMV and MPPT via the Venus - but it doesnt see any information from, or detect the Multi.

Is there a reason the VenusOS doesnt pass through the information coming in from the Multi?



bigal asked
Vance Mitchell answered ·

2 Answers

Gateway for Phoenix to communicate of CAN with Orion BMS

I'm looking for experience around controlling Victron inverters over CANBUS. I was told by Orion that their Jr BMS could shut down discharge to protect my battery over CAN, but would likely need some sort of gateway.

chris-knauf asked
wkirby answered ·

1 Answer

Intermittent VE.Bus Low Battery Warnings, but DC Volt is OK?!



I think, but I’m not sure, that the “VE.Bus System” listed above in the alerts is probably referring to a Multiplus II unit. I keep seeing intermittent warnings like this for no apparent reason. All Physical connections seem fine and actual battery voltage is nominal.


2 x Ve.Can MPPT working together in parallel

1 x Networked CCGX

1 x 712 battery monitor
1 x Latronics LS-5048 Inverter (5kVa 48V) as the primary inverter

1 x Multiplus II (to be used as a 70A battery charger)

All the Victron gear is communicating with each other perfectly.

I have shared voltage sense turned ON

The Multiplus isn’t always charging the batteries (in charger mode) when the generator automatically starts up so we have it switched to inverter/charger mode and that’s working as a charger even though it’s wasteful being left ON all day and night with no inverter loads.

Q. 1. What is this alert referring too usually?

Q.2. Does anyone know why the charger mode wouldn’t be working but the inverter/charger mode does work to charge the batteries when the generator runs? (Sometimes there are no Led lights on the Multiplus II)

Q. Are intermittent alerts like this normal?

ecoworld asked
ecoworld commented ·

1 Answer

BMV-712 V.E bus connection to CCGX


I have a CCGX that somehow isn't able to connect the BMV-712.

The V.E bus cable between BMV-712 and CCGX is 0,3m with one side right angle.

BMV-712 has a 10~15m UTP cable to shunt.

CCGX has a 10~15m UTP cable to the Multiplus 12/3000/120-50.

Connection between CCGX and multiplus is OK.

Connection between BMV-712 and shunt is OK.

When i press the "REDETECT" on the system setup on CCGX, it seem to find the BMV-712, but it doesn't connect it.

On the CCGX battery monitor page the BMV-712 information "flicker" on the measurements about every 10sec.

I haven't yet connected the CCGX to internetrouter.

What's the possible reason that the BMV-712 cannot connect to CCGX?

jens-martin-gunnestad asked

0 Answers

Orion-TR Smart 12/12 30 Charge Disconnect Question

Hi there,

i just purchsed a Orion-TR smart 12/12 30A isolated to istall it into my Van. I would like to enable low temprature charge disconnect as my lithiums could get below 5 degrees from time to time.

The manual states that i should connect it with a "Isolated remote ON/OFF cable" to the charge discconect of the VE.Bus BMS. Unfortunately i cannot find this kind of cable anywhere, could anyone point me in to the exact cable i need? Also, could this special cable be replaced with a simple wire from the VE.Bus BMS charge disconnect to the H-Pin of the Orion-TR?

As an alternative, could i also connect the VE.Bus BMS charge disconnect to the COM Port of my BMV712 and then connect the NC relay of the BMV712 to the H-Pin of the Orion-TR in order to remotely turn of the Orion-TR in case of low temperature?

best regards,


lofy asked
lofy commented ·

1 Answer

VE.Bus Error 5 Overvoltage on AC-Out

Setup (in an RV):

* 2x MultiPlus 24/3000/70-50 120V set up in master-slave configuration
** One each connected to a circuit breaker panel
* SmartSolar MPPT 150/70
* Color Control GX
* BMV-712

AC panels have loads distributed across them. Included among these are two RV aircon units, with soft-start capacitors added. When I run a specific RV aircon unit, which is on one panel, and another high-wattage device on the other panel, I get VE.Bus Error 5 and the accompanying 30-second shutdown of all AC loads.

Testing so far:

* Seems to be centered around the interaction between the inverters, one of the aircon units, and the solar system.
* Only happens when inverting. When on shore power, no issues.
* Seems to only happen when the compressor on the AC comes on.
* Second AC unit does not appear to generate the problem.
* Load at the time is anywhere from 1600 - 3000 W, depending on what I have running. Seems to initially require me to put a heavy load on the system, then I can get it to happen with solely the AC unit in operation.
* Slave unit always displays the fault. This inverter drives the aircon unit that I can generate the fault with.
* Have not tried cutting out the PV controller far have only cut the panels out (400A panel cutout switch, 80A controller cutout switch)

Any ideas appreciated.

malcolmdmoore asked
malcolmdmoore edited ·

1 Answer

Why won't my Quattros deliver rated charging power?

Over the last year, I've had three different Quattros installed with my LiFePO4 off grid system:

Quattro 48/15000/200,

Quattro 48/3000/35 120V,

and just today, a new Quattro 48/5000/70 120V.

I can make none of these Quattros charge my battery at their rated values (200A, 35A, 70A respectively).

The new Quattro 48/5000/70 120V is the latest example of this. When it is started up, cold, it ramps from 0A to 61A, but it will never attempt any higher. Shore current limit is set to 50A, and this is a 53.5V battery that is being charged, so there should be 50A * 120V / 53.5V = 112A of shore capacity.

The battery in this case is well below the absorption threshold, and the Quattro is configured for maximum charge current (70A) in VEconfigure.

The ambient air temperature around the Quattro is roughly 10C today.

The delta between the Vsense pair and the charging cables is 0.20V at the peak 61A charging, so the stated 1.0V maximum delta is not being reached. (Calculated cable resistance is 5mOhm.)

It even takes the Quattro a few minutes before the fan spins up to cool the unit. At no point will it attempt its rated value.

I observe a slightly different, but similar, phenomenon with my 15KVA unit. That unit is rated to 200A, and when it is cold and enters bulk charging, it will begin at 190A for about four minutes. It then drops suddenly and in a characteristic curve to a stable charging current of roughly 150A, which is only 75% of its rated value. A sample graph of the charging current is here:


In summary: my units don't deliver their rated charge under any normal conditions, and I can't figure out why. Is this simply what we should expect in terms of performance from these units? Should I consider returning the Quattro 48/5000 120V since it will seemingly never even attempt to charge at 70A?

ben asked
ben commented ·

2 Answers

Why CCGX cannot find VE.Bus?

I wonder if anyone can help me solve this riddle - I think something is broken:

Set-up: 2 x 10 kVA 48 V Quattro (2653433); CCGX (v2.54) ; 1 x SmartSolar Chargers MPPT (v1.06); 4 x BYD B-Pro 13.8kWh batteries and ESS with grid-tie enabled.

The Quattro and BYD batteries were working seamlessly together. but now they don't.

Quattro communicates with my computer but not from CCGX, sometimes works sometimes not, it confused me.

Resetting Quattro to default and reconnecting to CCGX as suggested by local distributor does not resolve the problem. Neither reconfiguring the Quattro.

The remote VEConfigure use to work but now fails during download: "

An error occurred during the downloading process.

Error Message: 'No VEBus product was found'

Error: mk2vsc-33" . I don't know what this means and have not been able to make it go away.

In desperation, I tried to re-upload the firmware. I did it without any issue.

I suspect these problems are related to one component malfunctioning most likely is the CCGX.

I would really appreciate any help.

Aydin Sadrzadeh asked
Aydin Sadrzadeh commented ·

1 Answer

Overload L1 on VE bus system

I often have that alarm cleared about 30s later. Last time yesterday at 18:47, maybe at the starting time of my washing machine, but not sure. Does not alarm me but I woul like to understand! My setup:

- Off grid, 2kWp on my roof + 23kWh lead batteries.

- 2 solar MPPT 150/65, 1 multiplus 24/5000/230

- BMV712, CCGX

Around the time of alert, exact time to be checked I am normally on my local sun time (UT+28m) but VRM may have some other tim:

  • 17:39: -0.40
  • 17:48: -121.00
  • 18:06 -7.07
  • 18:24 -24.90
  • 18:33 -5.90
  • 18:51 -3.60
  • 19:10 -6.7
  • 19:19 -124.60
  • 19:37 -128.00
  • 19:55 -8.10

Any idea?

Lionel SEYDOUX asked
ejrossouw commented ·

3 Answers


146 Posts
199 Users
1 Follower

Topic Experts

0 Points
0 Points