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macOS VictronConnect can't connect over MK3-USB/VE.Bus to Parallel Multipluses.

Situation: Initial setup of Dual Multiplus situation. Everything appears working, but no ability to communicate with Multipluses.

1. The MK3-USB was loaned to a friend who had no trouble using it. macOS shows it in the USB bus tree. Running the latest Ventura version of MacOS.

2. The Multipluses are reasonably late model, running 27xxx413 and 27xxx481 versions. They are giving different LED flashes but according to manual these are not VE.BUS errors. (no opposition flash to the inverter light, which is solid.)

3. The Cables connecting are highly rated Cat 6 cables, premade. Everything appears correct.

How to debug?

The VictronConnect app has two tabs, Bluetooth and VRM. Both of these work. When the MK3-USB is connected should another tab appear with the multiplusses? Or is there something that needs to be done in the app?

sailing-cat asked
sailing-cat commented ·

1 Answer

Multiplus-II dosen't re-switch ON over Remote Console


I have a Cerbo GX and three Multiplus-II in a three-phase system configured.

When I switch off the Multiplus over the remote console it turns immediately off.
Switching back to ON (remote console) has no affects.

To bring the Multiplus on again I must pull VE.Bus cabel out of Cerbo and the Multiplus starts few seconds later.

After reconnecting the VE.Bus cable it is all fine. Switching between Charging Only, Inverting Only and ON is no problem and works fine.

When I’m using the MK3-USB Adapter and the VictronConnect Application, the switching between ON and OFF works fine.


Cerbo: v2.93

MultiPlus: 501


pv-andy asked
pv-andy commented ·

4 Answers

Cannot connect my laptop to Multiplus II GX via Mk3-USB


I have a Multiplus II 48/5000 GX with Pylontech US5000 batteries and an ET112 meter.

I have tried in vain to connect to the inverter via the MK3-USB device.

HP Laptop operating on Windows 10

Cable Cat5e (approx 3m long). Also tried a Cat6 cable 6m long.

Can Cables to pylontech, Ethernet and ET112 remained in place.

I did have the MK3-USB connected in the Laptop port and the RJ45 connected in the free CAN port on the inverter when downloading the VEConfigure 3 software (I see on here some advice that this should only be connected after the download).

When selecting a communication port, it does give me a drop down 'Com 3 (USB Serial Port) and the device has a green indicator in my devices settings - am I to assume the drivers have loaded ok and the device is connected to my laptop?

I cannot however get beyond 'connect cable and switch on device'. Batteries are on and I switch the invertor to 1 (it then starts charging the batteries - which worries me as I have not checked settings).

After 10 or 15 seconds I get message pop up saying 'Help in Communication' and that's as far as I can get.

I can see the inverter on Victron Connect and the VRM portal along with my ET112. It has monitored power used when I switched the unit on). I managed to update the firmware via bluetooth using Victron Connect, but I cannot adjust any settings this way.

At present I have the unit switched off and I have run out of options.



andy-mullins asked
andy-mullins answered ·

4 Answers

Unable to connect with Multiplus via MK3 USB


I am installing a system using Multiplus charger/inverter. I need to configure the Multi. Hence communication between PC (Lenovo Win10) and Multi is required.

I have installed the VE configure III and I have a MK3 USB interface.

When I let the VE Config auto detect nothing happens i.e. the programme is doing a search and eventually times out.

When I try manual connection to e.g. Com3 an error message apperas saying "Cannot open Com3" - it does not help to change Com port no.

I have removed and re-installed the MK3 driver. In device manager I am able to locate the virtual serial port i.e. that part seems to work fine.

I have also tried to use the VE Bus Quick Configure software - and the error is the same

Any good suggestions?

p.s. I have tried on a different Multi and the error message is still the same. I have not tried a different PC yet - not so easy due to remote location

gustav74 asked
robandheaps answered ·

8 Answers

Macbook, parallels MK3 USB driver not available

I have a new 2021 M1 Macbook, running Windows 11 on Parallels.

I need to add a PV inverter assistant to a three phase Multiplus system.

The MK3 USB connected seemlessly with Victron Connect in Apple but no matter what I have tried I cannot get the MK3 USB to be recognised - "Driver is unavailable" by Windows or Ve configure tools.

I have have read numerous community posts and searched Victron information manuals, reinstalled the configure tools, rebooted, updated, set the USB drive, tried through VE Configure 3, tried numerous ports, tried through apple terminal, tried through windows many times and no luck.

The VE config says use the "found new hardware" assistant to specify the location but I can't find such an assitant any where.

How do I get the driver and MK3USB recognised ?????

greg0448 asked
Daniel Leone edited ·

13 Answers

VictronConnect 5.42 not finding Multiplus device on Windows with MK3-USB LAN


I am familiar with VictronConnect on bluetooth and Android - no problems there.

Today I purchased MK3-USB interface, installed VictronConnect 5.42 on laptop and desktop PCs, tried 2 brand new LAN cables to connect to new Multiplus 12|500|200 (which is powered on). VictronConnect simply reports "No devices found"

Have tried different computers and cables, reinstalled VictronConnect, turned firewall off, run as administrator. But result always the same, after a few seconds of searching: No devices found

What else can I try?

Thank you

gerald-d asked
tarpkir answered ·

3 Answers

MK3 Drivers

I cannot get the MK3 drivers to install on my Windows 10 machine. I have followed every tutorial, downloaded VE Config 3 and created the USB drivers. Tried to manually install them with no luck. Windows says it cannot find the drivers. Yellow triangle will not go away. I have rebooted, restarted, uninstalled, reinstalled. Any ideas? What is the exact filename for the driver?



bf-mining asked
sakara777 commented ·

7 Answers

MK3-USB interface not recognized by Victron Connect v5.8 on mac.

I'm trying to connect my older Macbook Pro to my Multiplus 24V3000/120v. I'm using a new out of the box MK3-USB interface. I've followed all the procedures: my Mulitplus is powered by DC. All other components are disconnected. I am using a Victron RJ45 Cat 5 cable to connect to my Macbook pro running Victron Connect v5.8. I tried running the older version of Victron Connect v3.2 and the newest on my wife's new Macbook, without success. The sticker inside the Multiplus reads: 2012120.HEX. What am I doing wrong?

kellystier asked
kwame commented ·

3 Answers

Extension cord for MK3-USB interface from basement to top floor office

Now that we know the MK3-USB interface cannot be connected to a network switch. Question is can an extension cord be attached to the MK3-USB interface ?

Attached is what I am trying to achieve - Will both extension cords work ?



satish asked
satish commented ·

1 Answer

Can the Interface MK3 - USB be connected to a switch with a USB/RJ45 adapter

I have acquired a Avaya network switch-box and would like to connect the MK3-USB adapter to the switch and then remotely connect my desktop on the top floor (wired connection to the switch). Firstly can the connection be made to the Network Switch and if yes will the existing Victron Direct sApp till work ?

satish asked
nickdb commented ·

2 Answers

question about MK2/MK3 protocol for setting AcPowerSetPoint / ESS 'Grid Setpoint'

Hi, i am programming some simple functions on top of the MK3 USB interface. I have read the 'Interfacing with VE Bus MK2 protocol' pdf from the site and i have most of the thinks working. My goal is to implement the AcPowerSetPoint via the MK3 interface.

Does anyone know that the correct MK2/MK3 protocol variable is for setting and getting the AcPowerSetPoint? (aka Grid Setpoint)

When i look at 'RAM variables' from the MK2 protocol pdf, i see ID 's 14,15 and 16 and that could be what i am looking for. Unfortunately these ID's don't seem to give the right values.

(Does anyone know the difference between ID 14 and 15? The text is the exactly same for both ID's but they return a different value..)



jeroenw asked
symbioquine answered ·

2 Answers

MK3 not connecting to multiplus 24/1600/40 on Windows 10

Greetings. I have two Multiplus 24/1600/40's that I would like to connect in parallel. I have been unable to communicate with them in any way. I've tried a laptop and desktop computer with apple iOS and windows 10 operating systems. I've tried VE Configure 3, and VE The drivers seem to work fine. No yellow triangle, and the device is recognised as an MK3. I've downloaded the drivers both from Victron website and directly from FTDI website. Tried completely wiping everything and starting over several time. The inverters and MK3 were purchased within the past year, just months ago. I've tried everything I can think of and there is absolutely no communication between the MK3 and inverter, nothing, ever. Please HELP!!!


critterfer asked
Alexandra commented ·

9 Answers

Is the "MK3-USB" dongle/interface electrically isolated from the inverter?

Is the "MK3-USB" interface electrically isolated from the inverter

ppe-sammy asked
klim8skeptic answered ·

4 Answers

MK3USB driver not downloading installing

Using Windows 7 and VE Config: Under special no listing of MK3USB (only MK2USB) , this has been described by several other posters here. Nonethe less, followed Mathias advice: save files, opened them up under device manager but again no MK3USB file to update. Cant use my Victron Multiplus Compact to charge my Victron Lithium batteries (which is mind boggling that the Multiplus doesn't have an easy preprogrammed lithium setting). Any help on this would be greatly appreciated. Thank You.

jraelson asked
Alexandra answered ·

1 Answer

VE Configure 3 MK3 USB but only MK2 drivers show

We loaded VE Configuration Tools; opened VEConfigure3; created a USB directory. The directory only shows a MK2 folder not a MK3 folder. With the MK3 device attached, I do not see the MK3 in Device Manager. There is an Unknown USB Device with a triangle under System Devices - Universal Serial Bus Controller; trying to update it fails with it saying it is the best (but I don't even know if that is the MK3 device to begin with). The Alienware laptop is Windows 11 would that be an issue? Also, my husband did this without the MK3 being hooked up to anything; would that be the issue?

I have searched the forum and seen a bunch of MK3 issues but not this.


ldc asked
jraelson commented ·

3 Answers


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