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Programming max inverter power of Multiplus II-GX using Node Red

Hi all,

I would like to use Node Red to program my Multiplus II-GX so that the max inverter power can be controlled by

(i) time of day (so that the dishwasher does not deplete the battery and the fan does not run at night) and

(ii) battery voltage (so big loads do not take it below the 47.0 volt cut-off limit).

Has anyone done this before? If not, where do I start (I have no prior knowledge of setting up Node Red flows)? Is there a Victron sandbox where I can try out ideas without risk of crashing a live system?


sharpener asked

0 Answers

Large OS Node-Red password

Hi Everybody,

want to set a password for Node-Red but I don't know how or where respectively. I understood that I have to modify settings in the settings.js but I cant find it.

Please can somone give me a hont hot to set up a password if it is possible at all?

Thanks in advance

senna1976 asked
senna1976 commented ·

1 Answer

Venus OS Large: Node-RED and Signal K

BE AWARE: welcome to post a nice screenshot to show what can be done here. But please don’t ask question or post issues here. See support section in the Venus OS Large manual for that.

Hello all,

As some of you know, something new is in the works, called "Venus OS large". This post is intented to start getting a large audience for it, as well as to recruite more help in further developing it.

This story is a bit longer than I usually type, here we go:


Venus OS Large is an extended build of Venus OS, it adds Node-RED and Signal K server.

Node-RED is a tool for connecting hardware devices, APIs and online services. It provides a browser-based editor that makes it easy to wire together flows. With it, one can for example program something relatively simple such as a relay to open or close based on a temperature measurement. As well as make far more complex algorithms, tying voltage, current, power or other readings and other data available from Venus OS or elsewhere together with outputs such as relays or control points of the Victron system. All without having to write real source code.

Also Node-RED features a fully customisable dashboard, viewable in a webbrowser - both locally and remotely, via the VRM Servers.

Signal K server is aimed for yachts, and multiplexes data from NMEA0183, NMEA 2000, Signal K and other sensor inputs. It makes all that data available for Apps, such as WilhelmSK, a highly customizable boat instrument display. The Sailing with Signal K blogpost on our website is a great read for more information and ideas.

Customisation & automation without needing to be a software developer

The value of above is that now you can self configure and customise your GX Device to do many of the things asked for here. And doing so without having to posses software developer skills. It will require patience, time and to be not too afraid of trying things.

Its really extremely powerful and I'm super excited about the possibilities.

Documentation & how to install


Venus OS Large is available for the Cerbo GX, Venus GX, MultiPlus-II GX and EasySolar-II GX as well as the RaspberryPi3 and RaspberryPi 4.

Want to help?

There are a few ways to help. First of all by simply installing and using it; and reporting any issues, or just that you're happily using it and what you are using it for.

The other is by helping others here on the Modifications section on Community. There is and will be no official support for Venus OS Large. Instead, we are referring users to turn here, the Modifications Space on Victron Community. You can help by answering questions.

Next, there is developing and improving the documentation; The manual needs further development, also the nodes and available measurements will need detailing and documenting, examples, screenshots, videos, it will all help adoptation and getting the best out of this. And we'll need more help for all of that that.

Lastly I am looking for help in development and support. First of all to further develop and support the Victron integration into Node-RED, ie. the node-red-contrib-victron package. Which will require nodejs experience, Linux experience, and preferably also experience with Victron products; ideally you'd be following and taking part of the discussions here on Community, (remotely-) debugging issues as well as suggesting and implementing new functionality in the said package.

Besides the node-red package, also the integration of Node-RED and Signal K in Venus OS needs to be maintained. Which requires a different skillset: deep experience and knowledge of Linux, but also the Open Embedded build system.


I can type a whole lot more about this, but have to stop now. Have a good Sunday! And if you have examples, or questions or comments, welcome to put them below.

Ps. Node-Red example flow:


mvader (Victron Energy) asked
jsrivet answered ·

24 Answers

Change AC input 1 from Grid to Generator using Node Red

Good morning

I need to be able to set the AC 1 Input value of a Multiplus 48/5000 in a VE.bus system using Node Red. The parameter is manually adjustable using the GX touch screen or Remote Console (Settings>system setup>AC input1). However, I cannot find any option to set this parameter via any of the preloaded Victron Energy Nodes or via any of the MODBUS TCP registers. The value can be READ using Modbus from com.victronenergy.system Unit-ID 100 address 826. However this register is NOT WRITABLE.


Does anyone have a suggestion to be able change this value as part of a Node Red flow?

I have written a Node Red flow to automatically change the ESS mode from Optimised to Keep batteries charged when the user manually starts his Diesel genset and manually switches the change-over switch. The end user starts this large 3 phase genset occasionally to run 3 phase irrigation pumps. Since the generator has surplus capacity, the user wants it to immediately be recharging the batteries when it runs.

The generators AC output drives a dry contact as an input signal on D1 of the Cerbo GX which is set to Generator.

When the state of D1 changes it triggers the Flow.

The problem I am having is that unless I change the value of Settings>system setup>AC input1 from Grid to Generator the Display on the Touch GX still shows the input as Grid with a zero Value


It is only once I change the value for AC input 1 to 'Generator' via the Touch GX that I am able to see the correct information



Why not then just leave the value set to 'Generator' all the time? The changing of the Value of AC input 1 from Grid to Generator seems to be more than just a display change. It changes the behaviour of the ESS system. If the only thing I then change is to set AC input 1 to 'Generator' while the system is still connected to the Grid and running ESS Optimised, the system changes its behaviour to power all loads directly from the Input source. The ESS status remains on "optimised" and the battery doesn't discharge or charge from AC Input source.

Sorry for the long explanation when all I want to actually know is how to change a single register. I trust it gives the necessary context.

craig-gebhardt asked

0 Answers

Weather controlled Minimum discharge SOC example using Node-red

I have an interesting NodeRed project - based on next day weather, it is changing the minimum discharge SOC on the GX device. So if next day it is sunny, it will configure the SOC to a lower level, if it is cloudy it is increasing the SOC. At this moment I have only 4 levels, but it can be improved. How I'm doing this - you need to create a free account on After doing that use the API generated on that site, put it in the openweathermap node, add your city name or coordinates, and you will receive the details for the next 5 days. I'm looking only at next day, between 9AM-6PM and the value used is called visibility. Having the average value for next day, the system will decide (every day at 3PM) how the SOC should be for the next 24h. There are lots of things that can be added. If you need any other info, you can ask. Or if you have something similar, please share.



Lucian Popescu (Victron Energy Staff) asked
fish answered ·

4 Answers

Sending a node red payload from one Venus GX to another?


Would it be possible to send a node red payload from one Venus GX (Venus OS Large) to another, using just the Victron back-end for networking, if the IP addressing and security could be solved?
I would like to send solar forecast once or twice daily to 2-3 Venus GX installs on the same offgrid island. Maybe using web sockets or similar, could it be done, would it be allowed?
What would the smartest way to achieve this be?

Many thanks for any helpful comments.

houser asked
houser commented ·

2 Answers

Cerbo GX send receive SMS via GSM ?

Has anyone used Node Red to send and receive SMS messages on their Cerbo GX For status and commands?

I have it working with an email plugin but sms would be nicer.

david-ross asked

0 Answers

Cerbo GX Storage Full?

Hi everyone,

I have a Cerbo GX installed in a remote system which includes a Multiplus, a few solar chargers and smart Lithium batteries. I have Venus OS Large installed and use Node-Red for some automation.

In general it has worked well and has accomplished what I need. But recently I have noticed some strange behaviours with the Cerbo not doing or reporting what is expected in certain situations.

In Node-Red, now when I go to make a change and redeploy, I get an 'out of space' error like so:

Error: ENOSPC: no space left on device, copyfile '/data/home/root/.node-red/flows_einstein.json' -> '/data/home/root/.node-red/.flows_einstein.json.backup'

I can't find any way to actually check and confirm the storage space situation and don't have physical access to the device for a little longer.

Has anyone had storage space issues with the Cerbo before? Why would it have filled up? Log files? And how can I review this?

Any insights appreciated - thanks!

liam-hogan asked
Stefanie commented ·

2 Answers

Feature Request: "Virtual Switch" for Venus OS - solved with Node-red


the virtual switch in the MultiPlus is a very useful and powerful tool. I'm wondering if this would also be possible to integrate in VenusOS similar to scheduled charging.

Some independent examples:

- Turn Multi off at 10:00 PM. Turn Multi on at 6:00 AM

- Switch critical loads on for 2h every 48h OR if Battery SOC is >90% AND PV Power is >100W

- Don't turn Multiplus on sundays

- Use Multiplus Charger only between 10:00PM and 06:00AM (probably because Energy is cheaper then)

- Switch Solar Charger off when DC-Loads were <5W for more than 24h (don't know why) and VE.Bus state is off

- Set Absorption-Voltage to 14,2V if Battery-SOC hasn't fallen below 90% for more than 72h

- Set Absorption-Voltage to 14,7V if Battery-SOC has fallen below 60%

- Ignore temperature and turn off compensation if voltage is above/under example-voltage

- Limit Output to 500W as soon as SOC reached <60% and AC-In is connected.

- Stop Discharging if PV-Power is lower than 200W for 1h and SOC has fallen under X%

- DON'T limit charge current if loads are higher than X

- Switch 230V to 220V on overload

and so on ..



porcini asked
Warwick Bruce Chapman commented ·

5 Answers

How to control charge current of Multiplus with node-red on Cerbo GX

For some years I have controled my Multiplus (old Version not II) with a raspberry pi via two DAC and the assistants for "Charge current control" and "Input current limit control".

Since now an extension of the solar plant took place, I wanted to use a Cerbo GX instead of the Raspberry Pi and do without the DA converters but regulate this purely via software. More precisely, by means of Node-red on the Cerbo GX.

But unfortunately I miss the possibility to regulate the charging current (of the Multiplus charger).

I have installed the "large" einstein- Firmware (V2.82) on the Cerbo GX and I have enabled node-red and I'm using the node-red-contrib-victron node.
Devices are: Cerbo GX, Multiplus 24/3000, BMV-700, MPPT250/60, MPPT 75/15.

The AC charger node reports "There are no ac charger services available. Please check that a ac charger is connected or try a different node." The "multi control" node has no input for charger settings too.

Question now is: How can I control the Multiplus charge limit with node-red?

Multiplus 24/3000/70-16 (Type Id 2612) FW is 209



erichabg asked
shaneyake commented ·

9 Answers

GX node red update frequency

Hi, I am wondering why the values comming from the Victron nodes (Energy values) refresh with a frequency o approx. once at 4 seconds so 0.25 messages/sec. I assume they should be sent more frequently.

OS 2.82 lage, HW: MP 2 GX

daba asked

0 Answers

How to switch power assist on an off via node-red?

For some years I have controled my Multiplus (I not II) with a raspberry pi via two DAC and the assistants for "Charge current control" and "Input current limit control".

Since now an extension of the solar plant took place, I wanted to use a Cerbo GX instead of the Raspberry Pi and do without the DA converters but regulate this purely via software. More precisely, by means of Node-red on the Cerbo GX.

But unfortunately I miss the possibility to regulate the charging current (of the Multiplus charger) and also the regulation of the power assist mode does not behave as expected.

I have installed the "large" Firmware (V2.82) on the Cerbo GX and I have enabled node-red and I'm using the node-red-contrib-victron node.
Devices are: Cerbo GX, Multiplus 24/3000, BMV-700, MPPT250/60, MPPT 75/15.

The AC charger node reports "There are no ac charger services available. Please check that a ac charger is connected or try a different node." The "multi control" node has no input for charger settings too.

Question: How can I control the Multiplus charge limit?

The input current limit can be read and writen by "Multiplus Input 1 AC current limit" in and out node but the behaviour is a little bit strange.

From 3 to 16 A current limit, all works as expected. i.e. when I set it to 5 and read it back afterwards, i got 5.
But when I set it to '0' , i got '3' when i read it back, but the Multiplus stops Power Assist mode (as expected). Is this (set to 0 to disable and set to >=3 to enable) the only way to enable/disable power assist?



erichabg asked

0 Answers

Why is the node-red-contrib-rfxcom node in Node-red not working in the "large" version?

I have a rfxcom device working on a rpi 3b+ running Node-red. I can control 433mhz switches and I read data from my 433mhz weather station. Working just fine.

If I connect that same device to my other rpi 3b+ running Venus os 2.82 large 30 (Node-red) than that node is just not working. Same goes for the node that controls my ultrasonic distance sensor (node-red-pisrf). With that I measure the level of a rainwater tank.

I had the same problem with the gpio pins (node-red-contrib-gpio) but I found a solution for that. I can control the gpio pins now without a problem and the node works ok now.

So....does anybody know how to get this working under Venus os large? Maybe some hints on where to start or look for a solution? If this is not possible then is there another system available for controling switches that will work on Venus? For my project I need to remotely control some power plugs. No possibility too hard wire.

Marcel asked
Marcel commented ·

0 Answers

Alert when generator is manually started

I’m looking to receive an alarm from VRM when a user cranks the generator manually. In my case, the mains for the generator are wired to the Quattro AC IN-2.

In the VRM all installations overview page a generator that is running manually looks like this:


We see that the generator is outputting 432 watts but the CerboGX says it is stopped.

Normally when stopped we should see Zero watts:


So, my question is how do I setup an alarm condition for generator voltage and or wattage at AC IN-2 when the CerboGX shows stopped? Not sure if there is something “canned” that with work or if I need to access the API of the portal and do something custom.

My Victron rep says it is not currently possible and that I should be able to do this with Node-RED. I have installed V2.82-large-30 and have enabled Node-RED. I followed this example and confirmed that Node-RED is working:

Does anybody already have a flow to accomplish this or can tell me how to do this with Node-RED?



tslewis99 asked
Kevin Windrem commented ·

1 Answer

Difference between standard OS and OS large with node-red


I have a ESS system with 3xMulti II 5k , Can-bus Battery (BMS with CAN comm. is my own development), SmartSolar MPPT RS and AC Inverters

Cerbo with os large image node-red

My problems is that the system is not automatical regulating the excess power from the Multiplus and Smartsolar (everything is working fine without the node-red image)!!!

With the standard OS image the Multiplus are regulating the charge power down if the voltage or the cell-voltages are over the limits.

But with the os large image 2.82 large30 I need to connect in node-red the "CAN-BUS bms battery current charge limit CCL" with the "ESS system current charge limit" to control the multiplus charge current depending on the can-bms.

But the smartsolar mppt rs is still ignoring the CCL setting, to get this working i would need to connect the batteryy voltage with the charge voltage limit in the DVCC menu but for this I cannot find a node in NODE-RED!!!

Hopefully someone can help me.



maureralex asked

0 Answers

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