Dear All,
Have any one integrated/ controlled an Multiplus-II GX with Arduino (ESP32) via serial?
Kept on searching and reading, but nothing found.
Application as below, without current transformer, but with serial control from Arduino. (Arduino is reading energy meter and would know how much energy is up and down every second).
Whatâs the point of all this?
Youâve installed the GX device, which can normally do everything.
If necessary, you can push the values to the outside via Mqqt using Node red.
I have solar panels.
Also, some water boilers controlled with analog SSR by ESP32.
So, idea is to use only solar energy to charge the battery, heat water and keep an eye on the meter.
Also, in the evening do peak shaving.
Full arrangement as below:
Configured as ESS?
Zero feed in is a standard feature of ESS, also with one Multiplus in a 3 phase grid
You could automate many with node red at the Gx device and mqqt or modbus.
Yes ESS.
As I am new here, I will check what this ânode redâ is. Thanks.
Sending outside data is not important. It shall be a stand alone system which simply does the job. I have no time to check my phone every time. To not say to make changes over phone. No way. I just need to do it, start it, and forget about it.
So, have u seen something like this done?
There are some possibilities to switch something at a certain SOC level
You can use the generator start/stop feature first
Other very easy way is node red . You can switch a shelly direct or send a message via mqqt or modbus to other devices in your network.
Also have a view at the ESS handbook
Dear @DirkW,
I keep on reading about Multiplus-II GX and try to understand if / how will fit to my situation.
I have 3x230 V network, with no neutral. Only PE.
In the manual of MP-2 is mentioned that neutral of inverter shall be connected to neutral of house network. But I do not have it.
So, will it work in my âfloatingâ network? Or what kind of different precautions shall I take?
In some topics I see a setting with âground relayâ. In my case I need to have that OFF?
Or, according to this paragraph from manual, ground connection would only be in OFF-Gride mode?
How do u see it?
What country are you from?
That sounds like bootleg ground (or a false ground), PE, and N in one conductor.
Please take a look at the different types of networks.
Switch to english
In my opinion, this works fine with the Multiplus, but requires a slightly different approach.
The grounding relay is only relevant in island/off-grid mode.
Even then, a bridge must be formed between PE and N.
Belgium. (3x230V + PE. Nothing else.)
Without N. Between PE and each phase is ~ 115V. Between phases 230V (in any combination).
If ground relay would be activated only on off-grid mode, then is perfect for me. I have no consumers on that line, except when city will drop and then I will manually disconnect from city and use off-grid line to supply the house (lights only)
So, would the âbridgeâ be the grounding relay?
Thanks.
Mening?
As mentioned, I do not have direct connected essential consumers.
No, not necessarely. Sounds like they use an IT system but with the feeding transformer in a delta configuration.
Victron does not support delta configurations, so three phase is out of the question. But im sure you could at least setup a single phase system, by connecting the L1 mains to L1 of the MP ACin and L2 of the mains to N of the ACin. Then of course disable the ground relay.
But im not sure if this would work as an ESS, first you would need to choose a gridcode, which i assume belgian delta grid is not on the list, and then the mains check could fail, since PE and the MPs N (which would be L2 actually) are not bonded upstream. In gridcodes the only belgian one is C10/11 ed. 2.1:2019-09 but what that actually means you would need to check with someone local.
But to be honest, all of this is the territory of a certified electrician.
I donât think I can help you with Belgium 3x230V + PE.
That doesnât exist in Germany.
But I found a link on the subject.
Indeed, no clear answer.
Iâve addressed the question with my house setup to Victron Belgium. Originally they have confirmed that it would work.
After reading all these and not finding correct and clear answer, Iâve asked them again. I would not be happy to buy the inverter and not be able to use it. Also, all these links and discussions are kind of old. Maybe there is a development, and new firmware would cover it. No clue.
Waiting for their answer.
I think the main question to answer would be, are you looking for a single phase victron setup or three phase?
I was thinking a bit about this, although im also not familiar with delta grid form, im intrigued by unusual stuff. Im sure you could use a delta-wye isolation transformer inbetween
However this would mean a local TN grid form on the wye side, which could not be allowed. I dont think you will get much better answers online, best to speak to a local electrician that knows your grid form and what is and isnt allowed on it
Single. Three phase would be too much and even there is no space for all of these.
Any trafo would increase costs, and changing already approved house network system would make things even more complicated.
Question: With no neutral available, what would I encounter?
âŠ)When using ESS the MP2 checks for a N-PE connection on the grid side before connecting to it. If thats not there, meaning the incoming neutral is not grounded, then it wont connect. But this check could be part of the gridcode, some gridcodes which are available as a selection do have notes about the neutral, but ive not read up what exactly the differences are. Im usually using VDE/German gridcode, and that for sure fails when no N-PE connection is there. (In your case, N of the MP would be fed by L2 for example, which is at 115V to PE)
In any case, you would very likely need to use the only belgian gridcode that is available due to legal reasons. The device itself of course also accepts an australian grid code for example. But this very likely would not comply with your local rules.
The grounding relay is only used in island operation, so whenever the grid is not available, thats correct. If you only use ACin for strictly ESS, and dont bother with ACout for emergency power, then the ground relay doesnt matter.
Is this what you have in mind?
As Iâve asked Victron Belgium, on connection but also ESS potential issues. I will wait some days hoping for answer / clarity.
I will let u know. I believe that there are aa lot of people seeking such info.
Yes, very likely you would be forced to use the belgian code. I think its this, but that needs a good read and you would need to know what local rules its referencing, in order to find out if your grid form is included or not
7.8 briefly mentions 3x230V without neutral grid, but if i understtod correctly, it only means that a newly installed power generation units needs to be able to be converted to 3x400V with neutral in the future
There is hope. I just need some reading and searching, indeed.
And I do not see here the need of converting. Only in case of 3 inverters as per first dot.
And here some progress.
Discussing left and right, it seams that a MP-2 GX can be connected to 3x230v without neutral. On 2 phases. L1 to L, L2 to N.
Grid code âBelgiumâ selected (no clue if this helps, but in my case this is what I will do).
Also, MP-2 GX fixed phase.
In up coming weeks I will purchase and start the project. First using a current transformer on one phase.
Develop the emulation of 530 via ESP32.
At the end, switch from trafo to power compensation over serial.
Nice project.
Attention. MP-2 GX is the âbudgetâ version. Check google comparing âvictron venus gx vs cerbo gxâ.
MP-2 GX has the Venus inside.
Some addition from meter manual:
