Hello, im new to victron stuff, waiting for victron gear to come to me from shop. And want to know did i buy all what it’s needed to get what i want.
I want to connect MultiPlus II to the grid and use it as a battery charger. Phase (AC) can not have higher load than 16A. So i want to achieve that if phase is not loaded (other devices in the house, phase is used not only by MultiPlus but the whole house uses it too) charger to charge at max possible amps eg. 16A AC. When phase is loaded by other devices, lets say dishwasher, i want MultiPlus to dynamicaly lower the maximum current it can use from AC. Can i achieve that by using ET112 smart metter? SO i could “tell” that AC can handle 16A, smartmetter will tell MultiPlus that 6A is used, so multiplus will charge (draw from grid) @ 10A not 16A?
PS so far i have ordered MultiPlus II, Cerbo GX, SmartMetter Et112 + wires of course.
Hi Tomas,
I’m not sure if you’re aware, but if you have your house loads wired to the output of the Multi, then it will do this natively. Grid is passed through as priority, and what’s left (up to the set limit) is used to charge the connected batteries.
But maybe you have another plan with the arrangement of your kit?
You only need the grid meter if you want to charge with excess grid-tied solar and build an ESS. If you want to use it purely as a UPS then you might want to put non-critical loads on AC out 2 if that is available on the model you ordered.
Thanks for replays, but looks like i need to add more info, cause all answers are not the ones.
I want to use multiplus as a CHARGER, nothing more, just a charger (for simplicity sake). AC output is not used, there is no solar panels, or something, pure AC charger.
But my house have 3 phases,i guess all houses in EU have 3 phase, anyway, multiplus gets one of phases and uses it to charge battery. I need that if i turn on dishwasher or any other devcie that also uses that same phase, MultiPLus to “sense” that and throttle down charging power. Let’s say i give it 50 AMPS, so it’s about (52*50 = 2.6Kw. 2600/230v) = 11.3 amps from AC (will be more cause it’s not 100% efficiency). And dishwasher uses another 10A - this will trip breaker, that is rated for 16A.
So charge should lower it to lets say 30amps (dc) while there is loads on that phase and go up again when there is no loads on phase.
Looks like smart metter is best answer, so victron will know how much phase is loaded and multiplus knows how much amps it draw, so it can calculate how much less it shoudl draw based on given MAX ac amps limit. But i can not find how to set up such simple thing.
But looks like victron did not have any tools to make this very simple and i guess very offten people’s problem, to solve it. The only thing i think of is using MQTT. So HomeAssistant [or some python script in Cerbo GX] will monitor data from SmartMetter and will send to MultiPlus AC limit based on phase load and available power from that phase.
The problem with this-that it may wear out EEPROM very fast. cause it may send tens of times per day new value.
I see that is easy. Here are a couple of ways to disable or reduce the charge current on the phase. When you get an energy meter you can check the current and disable charge if it’s too high or use DVCC to adjust the current lower. Here is a node-red flow that checks the current and if it’s over 10A disables the charger or you can use the one to adjust the current.
Hope this will get you started. The flow is in the text document if you want to try just adjust the parameters as required.
Thanks, did not wanted to go nore-red route, cause i wanted to integrate HomeAssistant and it’s much easier with MQTT, but thanks for directing me to the right path.
I neve rused Node-RED and looked at TXT file, i can not see how often it checks for current? Is this happening automatically? Who calls this node-red code? And how often?
Or it’s called, if we can name it like that, everytime any of variables changes?
Thanks in advance.
PS> strange that MultiPLus can not do that automaticaly with assistants. It would be much faster IMO.
I have a Shelly energy meter, and the current is sent every 700ms. I think the ET122 does it every 500ms.
Why use an assistant when you can use Node-RED? Assistants are terrible—you can’t customize how they work, they often conflict with one another, and there is no debugging.
If you have an RPi, you can put the Venus OS image on it and do some testing with the demo mode. Just install the large image and enable Node-RED. If you use HA, you will need to set up a separate unit and figure out how to send commands to the Victron unit. I’ve seen a lot of people use HA to send data to Node-RED and then to their other devices because the palettes are already there and easy to use.
As per my understanding assistants runs inside the device. Native code. So most effective. Fastest to react. Node-red runs inside Cerber GX (for example), it takes time to run code, to comunicate with devices and so on. it may take 2seconds before real action happens. Dont know how much cerbo gx is slow, still waiting for items to get to me. As i know it’s just raspberry pi inside with more ports. And i hate raspberry pi most overhypoed, overpriced junk ever made. For it’s price i bought normal mini pc with intel cpu, normal fast ram, ssd disk and so on. Off topic, but still salty about it’s pricing
It’s easy to send commands via HA and MQTT to Victron. IMO Node-RED consumes more resources in cerbo gx than MQTT. But i did not did test but i think node-red is heavier software than MQTT server.
Anyway thank you for answer! Will play with node-red and maybe it become my main tool I agree about ability to be able to change every detail, debug and so on. Im developer, but windows apps, not hardware code…and i udnerstand how important is to have ability to debug…write to 'console ’
If only we could program our own assistants. You could do something smart, like using a Shelly on the high-power device to send power data and check if it’s on.
When you turn the dishwasher on, it does not use 2400W immediately. It will start and do some pumping first. You could implement something smart to disable the charger or reduce charging for one hour while the high-power device completes its cycle.
Yeah would be cool to program assistants by ourselfs
Yes dishwasher first rinses only later turns on heater. But i want to make wife friendly system, she already knows a lot of what to do and not to do, dont want to introduce new ones
Best is to monitor phase, and not depend on devices. There is many devices like washing machine and so on on phase1, induction cooktop, grill on phase 2, phase 3 high power motor that pumps water from the ground, all phases pretty balanced to have 1 or 2 high power devices, so there may be new ones and best is to just fallow load and lower change current in case of phase overload. DOnt want to disable charging, its critical for me to charge as fast as possible while electricity price is low. And it may be only 4-5h per day…sometines never in whole week
Sorry id id not udnerstood your video… how you see what is quick and what’s not? why you show task manager? it suppose to show something? or it just aws open while recording?
I really like your node-red code and i will test how fast node-red, mqtt, native python code that runs inside cerbo gx and will choose the fastest one
I think you dont read what i wrote. Multiplus is used as charger what AC out?
If multiplus won’t even do any inverting at all. Also since when multiplus have ac2 out? it only have 1 ac out.
Also i CAN NOT connect “these loads” to an multiplus because “these loads” are inside the house and multiplus is in basement. House runs 3 phase electricity so i can not introduce 4th phase and have 1 neutral for all 4.
or i just did not udnerstood your anwer…also may be
I just used the task manager to crop the screen. Look how fast it changes from 10 to 50 and 50 to 10. Updating the settings is instant. You can see it ramps down pretty quick because the next update is below 10 amps on the DC current from the charger.
Oh!!.. i suppose to look at those small numbers bellow labels…i not even noticed them! yeah now i see what you had in mind. Thanks. Really cool to see that! Thanks for your time spent on me! really appreciate.
These are just ideas. It helps others as well. I have solved problems for myself by looking at what other people want to solve and improve some of the settings I have as I go.
Instead of having a hard limit you could change the charge current based on the load of circuit so when you are at 15A for example you might be around 2-3A.
most overhypoed, overpriced junk ever made. 