I have two Quattro 10KVA in my ESS system connected as 120VAC split 180 degree phase (240V total) in my home in USA.
I would like to replace my gas cooktop with a 240VAC 12KW induction one.
Obviously the two quattros can’t handle it on top of my home power demand, so I was thinking to add a dedicated MultiPlus-II 15KVA just for the induction cooktop.
It will work mainly as pure 48VDC inverter as long the batteries are charged, if the batteries are low I would just set it up to pull power from the grid.
No charger function needed in my plan.
My question is if I can just add it to my current ESS (eco)System, or the ESS can’t handle such separate/indipendent inverter?
I don’t think that your ESS will handle an additional independent inverter. An alternative would be to add another pair of 10kVA quatro’s in parallel with the existing ones. Otherwise keep the 15kVA as a totally independent system with separate monitoring if required.
Ve system configuration tool won’t allow you to do that.!! But it would be nice to be able to parallel a smaller inverter with a large one…
you already have 20kVA available cross phase, so I don’t think that your induction cook-top is going to take 15 kVA all the time. Perhaps monitor your load for a while and see how much spare capacity you have.
Victron does not support anything other than a parallel system with the exact same units. You can’t mix and match or use asymmetric devices, nor share batteries between independent systems.
You can build some of these configurations but there will be little, if any, support.
The only thing you can do is connect the new Multi 15k to the same battery, obviously through proper protections. You cannot connect communication to the old Cerbo. I also wouldn’t recommend supplying it with power in any form, unless you actually need its charging capability.
Connect only DC In and AC Out 1. This way it will work, but you won’t be able to manage this inverter remotely. For that, you would need a separate Cerbo dedicated exclusively to this unit.
Of course, this is not a setup supported by Victron, but there is a chance it will work correctly
Hello. Nice setup you have there. First i would monitor loads for your house and decide if another inverter is really necessary. Victrons handle overload quite well and also in ess mode they are connected to the grid and can pull the “missing” power from it. I will describe my approach and you can decide to inspire yourself or add another inverter.
I have build for one friend installation with 3x Multiplus 5000 (We are 3-phase country). He has lot of big loads (11kW EV Charging, 2 Water heaters (7.5kW and 2.5kW, oven , 11kW induction cooktop, heating mats in bathrooms which are 2.5kW each and so on… ) Long story short if all tries to run at the same time it would trip mains breaker even with Multis running full power . But key is that you just need to make sure it does not try to run at the same time. Simple wifi sockets or ones from Shelly (Recommend) cost close to nothing. Then I divided my loads into groups -
Necessary or high priority - Cooktop, owen and other things you dont want to turn off ever.
Then 2nd prio i have EV charging (It is nice to be able to get somewhere)
And last loads which can run at any time ( If water heater gets shut down for 5 minutes while cooktop is heating nobody really notices)
Then you build logic in your prefered system (Homeassistant or NodeRed in Cerbo) and there you go you can do wuite a lot with even lower powered inverters.
From my point of view 20kW is hudge amount of energy. And if you do it smart i am pretty sure you can run a small company.
Also if you are worried about cooktop being 11kW then just know that they are rated for that (needs to be big cooktop anyway , ours are 7.5kW and 2-Phases) It very rarely if ever hits this power. Ususally it is divided in half (two pots each) and each can get to the top power only with big pot and running on booster. Also Boost mode lasts about 2 minutes anyway. Then it derates and goes to lower power. Point is you dont usually boil 4 pots of water on boost at the same time and i doubt cooktop would handle it continuously anyway. So try to get it connected and observe if you arent pulling too much from grid. Anyway it will be bursts of few hundrets of watts every now and then when you are cooking. Not worth extra investment. And in case grid is down and you still wanna cook something just be aware to use only one pot at the each “zone” of cooker.
Guys thanks for all the support!
Tomorrow I have an online meeting with my distributor, I let you know how it goes.
My home here in USA needs a continuous power max of 12KW, peak don’t know but the 2 quattros never had a problem with big inrush current. According to the spec the quattros 10KVA can deliver up to 8KW of continuous power, which give me a 16KW max available in my split phase config.
The system is required to be idiot proof (my wife ), so I need more KW juice for the induction.
Did some homework, I think there is a small hope by using the AC Input Control feature, and the Vsense Batt in the Multiplus 2. The idea is to send a low voltage at the Vsense terminal to make the MP2 think the battery is low and it needs to get the power from the grid. Here below some details:
The K_ESS relay (one of the relay available in my ESS devices) can be easily controlled in NodeRed, so it will open when the ESS is pulling power from the grid…
Not sure if the MP2 ignores the Vbatt voltage at the batteries terminal if the Vsense Batt is present.
Finally in the ESS system I will enable the DC load option, so that the MP2 DC input is considered somehow in the ESS system.
All of this because the AC input control can not be tied to an input in the MP2, Victron maybe a feature to add?
I hope so as well, but it is not 100% confirmed in the manuals.
The local distributor salesman today confirmed me that the 15KVA MP2 is the cheapest solution to my problem, also comparing similar inverters of other brands.
However he did not know for sure if the Vbatt sense trick I posted above will work. Also here in USA is difficult to find the 15KVA MP2 230VAC in stock, so it will take a couple of weeks to come to my hands. This also means here in USA we are unable to test it.
The official solution of 2 more quattros in parallel was suggested, which means at least double amount of money for me.
As plan B I should buy an 230VAC 100A(!) contactor relay to power the AC input of the MP2 when needed…. still less money than 2 quattros, but (maybe) another layer of unnecessary complexity. KISS is my first goal.
And if you want to be absolutely Gucci connect SmartShunt as DC consumption meter before multi. That way you will also have accurate track of actual Multi assisting energy. Ofc dont connect Multi to the VE Bus. It could be possible via another VE Bus adapter (Maybe even MK3) But dont bother. You will not gain anything by it anyway. Monitoring wont work and control either.
So I need a way to tell the MP2 that the battery are below the ESS min SOC and it must pull power from the grid in this condition…
If I connect the MP2 at the output or the Quattros, the Quattros still need to generate the power for the induction, and this is what I want to avoid!
Anyway you basically solved my problem! 10e9 Thanks!
couple of easy question more:
can I set up the MP2 to output 60Hz 230VAC and not 50Hz?
If configured properly, the MP2 will not feed back any power like the quattros to the grid if this one disconnect. It is crucial my system will be Anti-islanding as currently is.….
you need to setup the same AC parameters as in quatros. VE configure is the same just in quatros you can set it up for two inputs.
And i dont know if you have quattros set up to disconnect from the grid but if yes it reports AC Input state "240” so you can read it via node red and switch relays on cerbo based on that.
10.3.8. PowerAssist
Use PowerAssist to prevent an external AC input circuit breaker to trip due to excessive load. If the load exceeds the AC input current limit the Multi will start inverting in parallel with the external AC supply and will provide the extra current needed. Note: When PowerAssist is enabled there is a minimum AC input current limit depending on the device type. Setting a lower limit than this minimum will result in the minimum limit. Note that in a parallel system this limit is per device!
so basicaly you would connect Multi on the output of Quattro. Then set up low power assist current i dont know 5A ? And when it will be drawing more then 5A then multi will join the party and push power to the load.
Or if you are comfortable with some programming i would maybe try this :
Connect Multis AC In to the AC Out of the Quattro. Then before the connection of the Multi (to account for its own current) clamp current meter and connect to Multi. Then set up the Power assist in Multi to arount 20-30A. Of course disable internal charger.
On quattro : You set up generator control to turn on generator (Drive a relay) when load is over certain amount. Then connect the relay from quattro to the remote input of the Multi.
This way you get : Much lower idle consumption of the system - Multi kicks on only when needed and assists the Quattro.
Also you get much higher power on the one phase multi is connected - size your cabling and fuses accordingly. And you can use it for example for EV charging . And Victrons EVSE will disconnect in case of overload of quattro so you are safe even when your wife cooks .
It requies more setup and thinking but i think its best approach.
), so I need more KW juice for the induction.
