Victron Multiplus, Micro-Inverter and Generator. Where does the energy go once the battery is full?

I always wanted to know (and some of you as well), what will happen if the battery is full, but we still have AC-coupled solar connected to the Multiplus and also a generator (or the grid).
Usually, the Multiplus would change the frequency at its output from 50Hz to around 53Hz to stop the connected AC-Inverter from producing power. However, this only works, if there is nothing connected to the AC-input of the Multiplus. As soon as it is connected to the gid or a generator, it cannot shift the 50Hz anymore.
So, where does the power from the AC-coupled solar go in such a case?
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[@keithcress1335]

Andy.... Where's it going? You pointed directly at it at 10:20. Notice the "generator" output is NEGATIVE meaning it's consuming not generating.

[@rcinfla9017]

Multiplus will not allow AC output voltage to rise. Assuming you have grid back feed disallowed, there is only one place left, other than AC output loads, for PV power to go. That is to batteries. It will be unregulated charging to the point where DC input to inverter gets close to exceeding maximum Multiplus DC input voltage limit at which point Multiplus will shut down. Other condition that will cause Multiplus to shut down is if back push power to batteries exceeds the power capability of Multiplus. There will be no regulation on battery charge amperage (other than Multiplus power capability handling shutdown). If off grid, toughest situation to handle is if you have a lot of AC coupled PV power with a lot of AC loads, then a large AC load is switched off. All of a sudden there is a lot of excess PV power that has to be absorbed by batteries until frequency shifting can back down PV GT inverter. This can take a few seconds to accomplish and the batteries/Multiplus must handle the excess during this time. When allowing AC coupling, most hybrid inverters will not allow batteries to be fully charged to hold a reserve margin to absorb a PV back feed with less danger of over-voltaging DC input to inverter. You can add a load dump system, like a hot water heater, to absorb excess PV power based on sensing AC back feed current or battery voltage rise.

[@cooltrkin]

My wife loves to here you talk, she said your accent makes her smile.

[@OffGridGarageAustralia]

Uh, oh, I have an influence on women... BTW, what accent?🧐

[@cooltrkin]

@OffGridGarageAustralia your German accent with an Australian twang. 😆

[@robfre70]

I have the same setup. When the batteries were full the MPPT's shut down (Float). The Micro inverter I (had) did not react to the higher frequency. It could not dump its load. The MultiPlus was making a very strange and loud noice so I disconnected the Micro Inverter to be safe. I bought the Deye 2000 Andy has. Thanks for the Video Andy.

[@mhelander]

Andy, your observation and especially your comment @ end confirms my observation how Deye 2000W micro-inverter works behind MultiPlus-II which is grid connected. I was initially afraid to have both AC sources available, used Deye only and added 375Wp panel to it so there is 825Wp panels in perfect angle for mid-day production. Unfortunately near arctic circle sun was so low that neighbor's roof was shading too much those panels and production was not enough to keep battery in charge without grid AC. Later I got lazy and had grid AC input connected with Deye in output side, to my surprise there was no problems. Battery is charged to full, then AC charging was completely stopped. DC loads were consuming battery charge and AC loads were served by Deye 1st and if not enough, from MultiPlus-II which took from grid AC all it can get (I've got input limit of 6A/230V because when driving I can boost DC-DC charging of the campervan with 12V/1200VA Phoenix inverter), for example when cooking using induction hob. After bigger loads, MultiPlus-II charges battery to full, then above repeats. Deye pulses power in, MultiPlus-II stops charging, AC goes idle, repeat. Unfortunately I don't have measurement of the grid export so dunno if excess is exported through MultiPlus-II, I was little worried about that but there is not much panels to feed grid and my house is consuming most of it anyways before grid feed. In my setup, without grid AC input, output frequency goes up until no charging is needed which stops power production from Deye. And it goes back to 50Hz when battery charging is allowed. Same cycle as above.

[@OffGridGarageAustralia]

Very interesting. So, you don't have the AC Inverter Assistent setup in your Multiplus? How does the AC Inverter shut off though when the battery is full? If the grid is connected, it can just export the excess energy unless you have turned this off. Probably not allowed on campgrounds anyway to export energy. Thanks a lot for sharing.

[@mhelander]

​@@OffGridGarageAustralia I've done similar off-grid island configuration as you've got. My rig is designed to be fully off-grid and campgrounds are out of the question anyways, only when parked near my house I'm using shore power. Most likely while on the go I'm using digital inverter generator if not driving, most likely then I'm not cabling both micro-inverter and generator. Long term plan is to purchase light box trailer, mount tilting rails for three 550+ Wp bifacial panels feeding to the micro-inverter. Use it to boost charging over winter or if using corded power tools etc...

[@KossuJahvetti]

Well ladies and gentlemen, Andy has just figured a technical way to call thunder god Thor on site by releasing 3rd dimension energy from its system.

[@OffGridGarageAustralia]

I think the thunder was a sign to stop these experiments! ⛈⚡

[@nostalgicamuseudevideojogo5565]

Andy you can program the shelly pm from the micro inverter to shutdown if voltage increase to 240v for x minutes or seconds you can also program shelly to notify you when that happen.

[@chuxxsss]

Stop sending thunderstorms , Andy😅. All good we need the rain.

[@FutureSystem738]

Thanks Andy - always great to see another video like this, interesting! When did you get thunder? Any rain? It’s absolutely PARCHED here. 😢 I have NO idea where surplus energy will go. As you said, it can’t go “to the grid” as your system is not connected to the grid.

[@ToddDesiato]

Power Factor my friend, Power Factor! It will phase-shift the current so that the energy is stored at zero (0) power factor as a circulating current through the inverter. The generator is probably the inductor and the inverter is the capacitor and the tilt-PV is the source. If you check, the current is probably flowing backward through the generator coils, and it is spinning with less torque.

[@OffGridGarageAustralia]

Well, there is no generator.

[@a-c-g]

You mentioned float voltage of 56.8V, do you have newer setting for float and absorption than what is published on your website, Andy?

[@philgavin]

It can go into the Generator ( off-grid inverter). That is also a bi-directional inverter charger and will charge that battery bank. Log into the other inverter, and you will see it isn't just a calculation. A Phoenix can have AC - -coupling and use it to charge. The Charger settings are available in the Veconfig software. They are just customarily hidden. When the Phoenix batteries are full it will raise the frequency to the entire system, and in doing so the micro-inverter will throttle.

[@TheRonskiman]

I suspect the above is correct answer, depending on how the Phoenix is setup. My Quattro has a AC connected PV inverter, and it is setup as an ESS system, but in the event of grid failure it will still power the house. My understanding is that if the system wasn't setup to alter the frequency when I have grid loss and the batteries are full, and too much power is being generated by the AC connected PV it would be dumped into the cells until the BMS shut off due to over voltage, then the whole system shuts down. I've not tested this, but have tested the frequency shifting, which works perfectly.

[@henvern]

But with Phoenix default settings it wouldn’t increase frequency, so would overcharge and/or shut down. I wonder why Victron don’t enable frequency shifting by default. It seems like a safer default. A diesel genset will increase frequency as load comes off. Maybe this is why Victron don’t recommend using inverters as the generator. Detailed config required to make it work well.

[@mjp0815]

Some advanced s*** this 😂

[@Full-of-Starships]

The manual does not mention anything about charging from the mains supply.

[@OffGridGarageAustralia]

How do I connect the Phoenix inverter to VEconfig software? It has no VE.bus, just Ve.direct. www.victronenergy.com/media/pg/VEConfigure_Manual/en/introduction-and-requirements.html

[@paulphone4767]

I suspect the Multi will go into Pass Through and the Phoenix will trip out to protect itself. Waiting with popcorn to see though.

[@OffGridGarageAustralia]

The thunder during this experiment was enough to make me stop, I think😄

[@thedolphin5428]

You are facing the same situation marine alternators face when the BMS shuts down and there's nowhere for the current to go while the alternator field (and stator) are still charged. Result: Massive, instantaneous (10ms) load dump with HV spike. Alternator rectifier diodes and all 12v appliances fried by 16v - 90v spike.

[@9111logic]

Thanks, Andy I was wondering, 230v but what is the current coming from the PV inverter? If there is low or no current flowing the voltage should not mean much should it

[@OffGridGarageAustralia]

It was around 130W, so roughly half an amp at 230V.

[@HybridShedIraq]

I was feeding back to the grid last spring and the Utility ac voltage reached 252v 😂😂. By the way Andy what you say about 56volts bulk voltage that you had set for the battery shelf?

[@BadIdea1123]

There is a second form of control (wont work for your situation) You need to have the network configured to allow for modbus tcp, if you have inverters compatible with victron they will take instruction for the cerbo regardless of the input frequency. But it requires that they are compatible (we saw the fronius inverter you had sitting in your shed in one video, that will work) There is only a couple of items that need to be configured for it to work But the AS/NZ 4777.2 (2105) standard does discuss voltage as potential for DRM as well, i thought it was as low as 265v

[@OffGridGarageAustralia]

Ok, that's interesting. I have modbus activate in Venus OS as I use this to connect to Home Assistant. That might be something in the ESS Assistant which controls DRM in a grid-connected setup. Yes, voltage goes up to 265V with the Volt Response Mode

[@kevinmills5293]

If your producing more AC coupled power than you need, it will back feed into the grid connection of the Multi. As this is a Phoenix, and probably has a similar design to the Multi, I would expect the power to back feed into the batteries of the Phoenix. If the batteries are full, the Phoenix will raise its frequency in the same way as the Multi does and this will be passed through the Multi and throttle the micro inverters.

[@jasondevine6014]

Ok so the Phoenix will still phase shift you reckon. This is interesting as in thought only the multi.would be capable.

[@mbr8981]

Das muss ja dann wohl so sein

[@kevinmills5293]

@@jasondevine6014 you might be right but Victron seem to describe the Phoenix as a Multi Plus without the transfer switch.

[@number40Fan]

Does the Phoenix have the ability to charge the battery? I don't think it does, but I'll look.

[@kevinmills5293]

@@number40Fan people on the Victron forum say the Phoenix will back feed into the batteries. I have an 15 year old Quattro and that supports ac coupled charging but it doesn’t do the frequency shifting.

[@klightspeed]

The inverter generator is probably acting kind of like dynamic brakes on a train, and trying to suck "rotational" energy out of the sine wave that the micro-inverters are trying to push "rotational" energy into (basically by shorting-out or reverse-driving the input side of its transformer on the lagging side of the sine wave). This would dump heat into the transformer and into the generator's windings. With an old-style direct-drive generator, it would speed up the generator until the frequency went out of spec.

[@mflo1970]

Hola andy ,te cuento mi experiencia, con variedad de reguladores,maximisadores etc hay una cosa muy importante que no debemos pasar por alto la energía, tanto la cargada como la descargada debe pasar por un gobierno de gestión y en mi caso confío plenamente en la gestión de carga que efectúa el multiplus ya que toda la energía pasa por el ,y cualquier intromisión de otros dispositivos puede hacer que esta gestión no sea del todo precisa y alterando los resultados

[@OffGridGarageAustralia]

Whatever that means, thank you.

[@stelaboys]

It's exporting back to the grid by raising the voltage higher than the input from the grid, a grid connected multiplus does this all the time the phoenix inverter is getting back fed and is likely handling it a bit but eventually you will will I suspect burn it out

[@OffGridGarageAustralia]

Yeah, good point, the 150W is probably what the Phoenix can cope with, with more it might go 💥

[@mflo1970]

Hola andy yo lo tengo así funcionando, tengo conectado un fronius a la salida del multiplus, y este aumenta la frecuencia para reducir la producción, pero tienes primero que configurar el victron, con asistentes te sugiero que busques en asistentes de la página victron, o veas webinards al respecto, un saludo

[@Juergen_Miessmer]

Hello Andy, the enegy goes into the grid. Your grid is the Phoenix. This means in case the Phoenix is not able to charge his battery, it has to fight against the miroinverter. This causes the Phoenix to heat up. Maybe it can endure the 200W, but if the sun comes out and your microinverter ramps up to full power your Phoenix will hopefully protects himself by switching off, otherwise it will die. In case the Phoenix protects himself, the Multiplus then can increase the frequency.

[@OffGridGarageAustralia]

That is the most logical explanation so far, I think. The power from the micro-inverter was just too small to make something happen. I'm too chicken to test this with a higher AC-inverter power though.

[@Full-of-Starships]

Andy has grid feed-in disabled in his MultiPlus for safety reasons. I've just spent a while arguing with myself whether this means that the MultiPlus blocks itself from sending power "back" into the "grid" (actually the Phoenix). Hmm???

[@Juergen_Miessmer]

@@Full-of-Starships Yes, the Multplus itself will then not feed into grid, but the microinverter will do. The Multiplus can not control the microinverter as long as it is operating ongrid. I dont know in detail how the Multiplus is internaly wired, but usualy all hybrid inverters i know do connect input and output together by relay in ongrid (grid paralell) operation.

[@aidendeem903]

The multiplus is reading -266W which may suggest that even if it is set to not back feed into grid AC it is unable to regulate the micro PV inverter. Has Andy set Multiplus to not backfeed?

[@Juergen_Miessmer]

@@aidendeem903 Regulation by increasing the frequency is only possible offGrid. But the Multiplus runs 'on the Grid' comming from the Phoenix. The Multiplus can not control the the Phoenix. The Phoenix has no microGrid function, due this it can not change its own frequency.

[@kurtmiller7945]

Ha, wenigstens Dritter😆 Los Andy, Her mit dem Pokal😂

[@OffGridGarageAustralia]

🥉da hast'n 😁

[@kurtmiller7945]

@@OffGridGarageAustralia Thanks a lot mate....wirkt aber sehr angepisst ??? Why ?

[@OffGridGarageAustralia]

@@kurtmiller7945 hatte das Smilie vergessen 🍺

[@marcorobbe9003]

Hey Andy, maybe you use NodeRed and a DTU to shut down / limit the power production of the micro inverters.

[@OffGridGarageAustralia]

The micro-inverter is connected through a Shelly 1PM so this is actually an option to turn this off if certain situations occur. Home Assistant is another one...

[@sparkletornado5890]

Could you use somthing like a Shelly Uni to sense the voltage of one cell and disconnect the shelly switch connected to the micro inverter at 3.5v - 3.65v or some other arbitary voltage that determines the battery is full?

[@Dutch_off_grid_homesteading]

Heya, I'm in winter here in Holland and making only 400-800 Wh/day so I have to install more solar panels ( but have to safe for it )

[@lerrypage]

Hallo Andy! Die Anzeige ist richtig, die Energie geht zum Phoenix-Inverter. Ober er die Energie vernichtet oder in die Batterie zurück lädt lässt sich einefach mit einer Amperezange am Batteriekabel messen. Bei meinem Steca-Inverter lädt er in dieser Situation tatsächlich in die die Batterie zurück.

[@OffGridGarageAustralia]

The Phoenix is a simple off-grid inverter. It cannot take any energy on the output or even charge it back into the battery. There are main components missing in the inverter. Or maybe not...?

[@lerrypage]

Alos ich kann mir technisch vorstellen dass es mit Invertern mit 50/60Hz Trafos funktioniert bis zu der Leistung, die auch der Inverter liefern kann (aber nicht mit Hochfrequenz-Trafo-Invertern) @@OffGridGarageAustralia

[@nikolaosvelissariou7107]

You can connect the PV micro inverter on AC-out-2 of the multi and then set up an assistant for programable relay (actually 2 instances of the same assistant for on and off), in order to turn on, or off your PV micro inverter, depending on the DC voltage, or Battery SOC.

[@robfre70]

Hi, will there be power on the AC-out-2 when here is no AC-in? I have the same setup as Andy. NO GRID.

[@Lulastyle]

Hi Handy, I have the same problem as you with the microinverter, do you think it could be a solution to connect the microinverter to the ac-out 2 output and using the assistant to set the relay 2 which disconnects at 99% of the soc? I'm waiting for your reply or better yet a nice video. Thank you

[@fdsa3f3cas3w]

I thought that when the load==AC coupled PV generation it would then disconnect the generator. Now it has disconnected the Generator it can then increase the frequency to reduce the output of the AC coupled PV. This assumes your AC coupled PV is on the AC2 output of the Multi-plus.

[@OffGridGarageAustralia]

It does not disconnect the gen though. It stops taking power from it, but the gen still sets the 50Hz for the whole system.

[@fdsa3f3cas3w]

@@OffGridGarageAustralia There seems to be a hub-2 Assistant that does disconnect. But seems to warn against using that as can then struggle with power spikes. Glad you pointed this out as I though I could AC attach some micro-invertors to a grid attached system and it would frequency shift. Now I realise only reliable route is to go down the Fronius route which seems the only supported way to avoid grid export (which I can't do here).

[@patrickp.5976]

Hi, is there a way to identify, at the Victron system, if the full power from PV Panels is loaded? I sometimes have the impression that my charing is limited by either the smart shunt or the Daly BMS but where would I see this ?

[@OffGridGarageAustralia]

Several locations to check: MPPTs, Multiplus and DVCC

[@claudev.k2]

I think I asked for testing this scenario 😅 Next step should be the measurement of voltage and current with an oscilloscope to check their shape and phase shift. It could be that it is all reactive power (Blindleistung) and the Victron and the microinverter are a bit confused with 90° of phase shift.

[@mbr8981]

Blindleistung ... ist das nicht der Schaum im Bierglas?

[@claudev.k2]

@@mbr8981 Ja, genau 😄

[@OffGridGarageAustralia]

What would make the inverter shift phases though? They would need to go opposite directions, one inductive, the other capacitive to compensate for the surplus power.

[@teardowndan5364]

​@@OffGridGarageAustralia There is no "excess" power if the inverter and generator are incorrectly calculating "power" as AC RMS volts x AC RMS current measured and calculated based on internal parameters. The inverter is likely only putting out 15-20W net to compensate wiring losses from 150VA getting bounced back and forth between the inverter and generator output filters.

[@luisaviles6066]

This energy go to the consumption of to both inverters, and also to every bms. I think.

[@brendankehoe7198]

heat loss in the phoenix inverter perhaps?

[@OffGridGarageAustralia]

It could be that the Phoenix burns off this small amount of energy coming back to it.

[@nicmate2543]

I think Mr. Andy needs one or two S.P.A.Ts and everything will be fine 😊

[@OffGridGarageAustralia]

It's always fine afterwards. S.P.A.T. for the win🍺

[@peetbraun9439]

Doesn't have the MP a contactor inside, witch can disconnect the generator, and then increase the frequency?

[@KevIsOffGrid]

thats what i was expecting - but no, thats not what happened.

[@OffGridGarageAustralia]

You usually use the relay in the MP to turn on the gen when the battery is low. You can also use it to turn it off when the battery is full, why not. So that could be a safety mechanism you can implement.

[@showme360]

Does the Generator have the ability to burnt off the excess energy (at a limited level) through a heat sink, can you see the temperature of the Generator rising? Do you have any dry connacts between the Generator and Micro controller, or a third party swict to trun off the DC voltage from the Micro controller, that you can use to control this voltage problem?

[@OffGridGarageAustralia]

Well, the 'generator' is the Phoenix inverter in my case, so, no, it won't take a single W of reverse power. I have a Shelly connected to the micro-inverter which I can programmed to turn off this source. But this was more for testing purposes and such a scenario would not occur in my setup ever. The 'genset' never runs unless I turn it on manually (again more for testing purposes than anything else).

[@adrionvanbeurden6365]

Hi Andy I’ve installed 15kW of solar in the central coast of California. In one of your videos you mentioned a bitcoin miner for your surplus power. Which mining pool do you recommend?

[@AveRage_Joe]

I Vote 💥💥💥💥😅

[@OffGridGarageAustralia]

I was waiting for your comment! 😂

[@greensolardiscussion1476]

I have a grid connected multiplus II with PV generator on AC OUT 1, It does change the frequency when the inverter is not allowed to feed back to the grid. So AC IN and AC OUT 1 can have a different frequency.

[@marcelvanlieshout3508]

I am studying on installing such a system and did not expect the Multiplus doing a frequency-shift whilestill being grid-connected. Are you aware of any Victron documents that may shed some more light on this? Specifically AC-coupled PV in a zero-grid-export multiplus installation.

[@greensolardiscussion1476]

@@marcelvanlieshout3508 In the ESS settings you can decide if you want AC coupled PV feed to the grid or not

[@greensolardiscussion1476]

​@@marcelvanlieshout3508 Sorry but every time I comment here, it is removed. I followed victron online courses. I use the ESS function that must be configured as an assistant. If you don't need ESS you can just add the "PV inverter support" assistant.

[@OffGridGarageAustralia]

Is this maybe turning off the transfer switch in the MP when you disallow exporting? Because if you have a large load coming online, the MP would not be able to lower the frequency quickly enough and it usually takes such power spikes quickly from the grid. If you post links, the comment will be removed. Sorry for that, KZbin does not give any other option.

[@marcelvanlieshout3508]

@@OffGridGarageAustralia perhaps it uses the batteries to satisfy this surge?

[@jasondevine6014]

No mp won't stop charging. Can you connect a relay based on soc.

[@OffGridGarageAustralia]

Yes, I can. The Multiplus has got one built in. I could use it to turn off the Shelly of the micro-inverter.

[@jasondevine6014]

@@OffGridGarageAustralia I would definitely do that. I just had a fire from a ac coupled inverter not turning off due to a BMS fault I believe. You are getting away with it at moment because of small AC couple but you really need to control it. The Phoenix is a low frequency inverter and any excess power freewheels through the clamp diodes on the MOSFET drive back into the battery. Mine diy inverter works the same.. it has no way of stopping that power other than turning off the AC output to the microinvéters or relying 9n frequency shifting.

[@OffGridGarageAustralia]

@@jasondevine6014 it never occurs in my system. This was just for a test. The gen/Phoenix does not come on automatically.

[@Lulastyle]

Hi Andy, I would like your advice, I want to add 3 panels to my victron system, due to a shadow problem I would like to add some optimizers, but the victron mppts get ruined with the optimizers, I can't put a variator on each panel because the voc is only 34 do you have solutions? Thank you

[@OffGridGarageAustralia]

I tested optimisers with Victron MPPTs. Not good. They basically start fighting over the max power point of the panels. Optimisers give no advantage with partly shading. There is a Danish study and they have tested all scenarios and compared them. www.solarquotes.com.au/blog/panel-optimisers-danish-study/

[@Lulastyle]

@@OffGridGarageAustralia thank you very much for the answer, I saw the Danish study, my problem is that having a house that shades me would mess up the whole string of 3 panels, maybe I can put micro inverters on each panel. but I would have the double transformation to charge the batteries. I accept advice, thanks bye

[@OffGridGarageAustralia]

@@Lulastyle The optimisers will not help with party shading. They probably will make it worse. At the end you cannot do much about it in a reasonable manner than just leaving it as it is and live with it.

[@KevIsOffGrid]

4 mins in ... what I'm noticing here is that the micro inverter has turned "off" way before the DC MPPT's have. I'm wondering what the sensitivity difference is in low light.

[@KevIsOffGrid]

and very strange at the end, with VRM showing it going to the Pheonix ..... Hmmmm - will sleep on that one.

[@OffGridGarageAustralia]

You should have kept watching a bit further 😉. The thunderstorm rolled through and hence we saw no solar production for a while. Yeah, the Phoenix cannot take any power normally. Interesting thoughts from some here about this...

[@VinayJhinkoe]

I can confirm the microinverter works at 270Vac

[@OffGridGarageAustralia]

😮

[@VinayJhinkoe]

@@OffGridGarageAustralia yea it gets that high only when i export to the grid with about 4750W. I only have 127v grid connection but with my own splitphase transformer

[@timchambers5242]

These extreme events are worth testing for system safety. Don't always trust the apps. Can you measure voltages & current flows between the various parts of the system? Using clamp meter for current will be less accurate but better than alternatives. Measuring voltage with different meters I have at home give different values. Standby power usage of inverters? Is charging of batteries really all 0 in this situation?

[@OffGridGarageAustralia]

Yeah, that is a good point. I was actually hoping for a bit more power coming from the micro inverter that day but the weather🤷‍♂️ Even measuring these smaller currents can be tricky and may lead to false assumptions. I can also only measure one voltage at the time and find it difficult to remember all the numbers and make sense out of them. The main think here was to get people start thinking about such setup and system designs and what potentially could happen. Even these rare occasions might be worth thinking of.

[@SchwarzwaldEnergiejunkie]

Energy is like Water, if there is nothing where to flow, it will not flow. It's like an generator running w/o Load, nothing will happen... ;-)

[@sirmonsterle]

5:05 I would think the Multiplus will disconnect the AC in. Then it can adjust the frequency. Or maybe the whole Australian continent will explode 😱 Hoping for the first version 😉

[@OffGridGarageAustralia]

It will only disconnect the AC-in if the specs of this AC source are out of the set values in the Multiplus. So, under and over voltage for example. I've never seen the MP actively disconnecting the AC-in. Even if the battery is full and the 'generator' is connected, it just throttles the power it takes from AC-in down to 0W basically. No explosion. Yet.

[@peterwalker7869]

Isn't it obvious? Frankenstein is alive.

[@OffGridGarageAustralia]

It looks like it!

[@mbr8981]

Die Energie wird per Unterseekabel nach Deutschland exportiert

[@martijnheeroma5492]

Unterseekabel ist kaput ;)

[@mbr8981]

@@martijnheeroma5492 wieder mal weg gesprengt?

[@GapRecordingsNamibia]

😂🤣

[@OffGridGarageAustralia]

Dooooh!

[@Full-of-Starships]

Hey, @OffGridGarageAustralia. Do you think "ECO mode" on the Phoenix could be useful? "When the inverter is in ECO mode, it will reduce its power consumption by approximately 85% when there are no loads connected to the inverter. When the inverter is in ECO mode, the inverter will switch to search state when there is no load or a very low load. While in the search state, the inverter is off and will switch on every 3 seconds for a short period (adjustable). If the inverter detects a certain size load (adjustable) the inverter will go back to normal operation mode. Once the load drops below a certain level, the inverter will go back to ECO mode." Programmable relay can also be programmed to indicate whether the inverter has been switched off. "In ECO mode, the relay will be closed both when searching for a load and when fully on, ie. load detected. Use this option when you want the relay to signal that there is power available on the output of the inverter."

[@Full-of-Starships]

BTW, I assume that the MultiPlus will then be able to modulate the AC frequency to turn off the micro inverter if required. As for what happens when the AC frequency is high and the Phoenix does one of its "searches" - 🤷🤷🤷 Good subject for a video. 😊

[@Full-of-Starships]

Also, didn't you originally have the MultiPlus configured so that it would switch on the Phoenix above a certain demand? ISTR you installed a switch between the two, but can't remember whether it switches this behaviour? Would it be worth going back to that with a very low startup threshold?

[@OffGridGarageAustralia]

I tried this at the beginning but the concept only works if you have this sitting on a boat or a cabin where there are times without any load connected. And in these circumstances you want to save power. For a normal off-grid installation that's not an option. If it is set to say 50W threshold and you have only a router connected, it will constantly turn off your internet as the load is below the threshold.

[@Full-of-Starships]

@@OffGridGarageAustralia This is the point. There was no load on the Phoenix. In fact, you were feeding energy INTO the Phoenix. The diagram showed NEGATIVE load. As I read the manual, it detects when the current it generates is not being consumed, which seems to be exactly the case here.

[@Full-of-Starships]

@@OffGridGarageAustralia If the load is only 50W then the MultiPlus doesn't need support from the Phoenix, which is why the Phoenix can switch off and all the mains power comes from the MultiPlus & the micro inverter. Since the MultiPlus is no longer tied to 50hz, the micro inverter can then be throttled off via frequency modulation.

[@uwe6734]

Mein Problem ist, das der Generator 53-53Hz macht und der MPl2 das nicht annimmt

[@opless]

#5 ;-)

[@83kaszas]

it went into the consumption of all the equipment

[@OffGridGarageAustralia]

130W? The MP has a consumption of 18W and that's about it...

[@mdatharjawedkhan4277]

Sir my neey 4gen balancer is not connecting please help me. When I am connect all the connection then blue and red light blinking please help

[@PierredeVilliersLife]

🎉🎉🎉🎉

[@OffGridGarageAustralia]

🥇

[@cyberplebs6577]

🐸🐸🐸🐸

[@davidpenfold]

It had been 4 days, I was getting withdrawal symptoms! That's an interesting conundrum. Why is it showing energy going to the other inverter? Does it have some sort of load capacity like wind inverters? Once installed, my two SMA dual string inverters are meant to be controlled by increased frequency too, so the question would be the same (as we have grid input too). But they and the SMA hybrid inverters will also be connected via Ethernet/WiFi so maybe they can control the string inverters that way too. I know this isn't a solution for you, and I'm not sure it is for me, so thanks for sharing this. I don't want potentially 10kW flying in uncontrollably 😮

[@OffGridGarageAustralia]

I'm not too concerned in my case because I don't have the genset running when the battery is full. It was more the question, what will actually happening in these rare occasions and raise a bit of awareness. In your case, the communication between the devices could be what will prevent any escalation in such a situation.

[@davidpenfold]

@@OffGridGarageAustralia maybe my expensive SMA Home Manager will be of use, as it sits right after the grid, so could potentially isolate the home system from the grid if needed. It's a hefty little piece of kit for its size.

[@ffs5310]

Cant the Phoenix Inverter charge the battery?

[@adon8672]

In his example the batteries were already full.

[@ffs5310]

@@adon8672 ok at least the first part was only the multiplus battery there was full, as the "generator" was on another battery, maybe i misunderstood 😁

[@OffGridGarageAustralia]

The Phoenix inverter is an off-grid inverter, so cannot take reverse power.

[@teardowndan5364]

Is any of the equipment actually able to distinguish real power from reactive power? My guess is the equipment was not programmed to care about reactive, real and apparent power and is doing a dumb RMS current x RMS volts output power calculation instead of proper i(t) x v(t) integration. By plugging two inverters into each other, the only load they see is each other's LC output transformer and LC filter. You are seeing almost pure reactive power bouncing between inverters being incorrectly reported as watts instead of volt-amps (VA) with the true PV output being a much lower amount to offset wiring losses.

[@OffGridGarageAustralia]

The smaller inverter shows actually VA instead of Watts. But yeah, you're right, This is not well displayed in the apps.

[@HybridShedIraq]

I made kaboom to two inverters trying to charge from cheap small gasoline generator 😢😢.

[@danielvanaalst2460]

If there is no way to "burn" or feed the Energy, the same thing would happen if you don't configured the multiplus with AC Inverter. The frequency wouldn't raise, the AC voltage wouldn't raise, but the DC voltage would raise, until the BMS trips. at 56.8V that could happen very fast.

[@OffGridGarageAustralia]

The DC voltage does not rise above the set Absorption voltage though. Never. It turns off all power sources connected to the MP. But what happens with the AC inverter if the frequency cannot be raised?

[@danielvanaalst2460]

In case the Multiplus is not configured with an AC inverter it does. I have tested this a few month ago (without grid connected), to see what happens. So priority of the multiplus seems to be the AC voltage. The AC voltage stays at 230V 50Hz, but the DC voltage raised until the BMS tripped. And I think this is much better than raising up to the AC voltage limit and damaging some of your devices (poping some capacitors) when there is an generator connected, I would assume, that feed in is disabled so the only way to not feed in is to send the power to the battery. Wrong configuration should not be possible. I assume that the multiplus would not connect to a generator when the input is configured as grid.​@@OffGridGarageAustralia

[@OffGridGarageAustralia]

@@danielvanaalst2460 Ah, OK, so no PV-Inverter assistant... OK, that's a very special case and a 'wrong' configuration which should not happen. But interesting to hear. What happens once the BMS has disconnected, does the MP just turn off? My MP keeps running if there is enough solar available, even without battery.

[@Raphael_Hofmann]

If you have no AC-PV-Assistant installed and no Grid / Generator connected, the MP-II will increase the battery voltage and eventually shut down, once the BMS disconnects. In your situation, the "Generator" will take this excess energy and heat up and eventually shut down or burn out, if it does not bidirectionally charge your second battery bank.

[@OffGridGarageAustralia]

It will overcharge the battery? Or at least trying to? I thought it will protect the battery under any circumstances... Well, in my case, there is no way the the Phoenix will take any energy at all. Will the MP try to push this energy back to the grid even knowing there is no grid as such? Not sure if the setting in System Setup and assigning the AC Input1 to either Grid or Generator makes a difference there.

[@Raphael_Hofmann]

Well, I could not try that jet and I am not quite willing to sacefice a Inverter or Generator for this experiment @@OffGridGarageAustralia 😅 But I just found out...if you forget to install the PV-Assistant (with not Grid or Generator connected), the Inverter will not increase the frequency and therefor try to overcharge the battery with the excess AC-PV-Power.

[@tristramsnowdon5256]

I thought Australian Standards required inverter shut down above 253V (10 minutes) or 258V peak. Your micro does not meet AS and shouldn't be used

[@tomasbolt]

In Europe it’s 253V

[@frostyfroze7352]

It’s 100% off grid, no grid connection, the off grid phenox inverter is connected to the grid input of the multi plus

[@rjinhobart7748]

Measure the currents for real. You can't really trust what is displayed because some of it might just be a back-calculation of other readings. When it was in the in the charging mode with the battery at 100%, the power of the tilt and the generator (running at about 97% efficiency) added up to equal AC load. eg at 11: 40, tilt is 91w, gen is 682w, load is 756w. (756-91)/682 = 0.975 efficiency from the gen - that seems reasonable. It's must be doing a double conversion (otherwise it's unable to change frequency) hence there will be losses. No idea as to how/where it was sending power back - you need real measurements.

[@OffGridGarageAustralia]

Yes, that is correct, some of the numbers are just calculated and related to other measurements the system actually takes. And the numbers where quite low, so there are some errors in this observation.

[@edwardvanhazendonk]

The "grid" multiplus is ordered to charge it's batteries. The multiplus 3k.

[@CHloras]

Andy, what kind of bitcoin miner do you run?

[@RichardSteigmann]

I suspect that the generator is burning the energy. 200 watts isn't that much if 2000 disappear somewhere then things get interesting😅😂

[@panospapadimitriou3498]

waiting until cold sunny day hits and use thermal camera!!! in every possible spot

[@OffGridGarageAustralia]

Yes, you could be true, Richard. I'm too chicken to test this with clear sunshine.

[@Zirrad1]

Has anyone tried connecting the Microinverter output to the generator input of the multiplus?

[@OffGridGarageAustralia]

That will only work with a grid connection. The micro inverter needs a grid form to start up and producing power.

[@JJMentz]

Andy has created dark energy.

[@OffGridGarageAustralia]

Hahaha, yeah, I did somehow...

[@deh_developer2725]

Kboom?

[@mornmorn8425]

The microinverter is delivering less power, cause its capacitors is staying full! It could lower mppt voltage, and, or, go in fault mode as well.

[@OffGridGarageAustralia]

But it's a dumb micro-inverter. As soon as it sees the grid, it delivers all the power it can. Until it hits 52.8Hz or 275V...

[@mornmorn8425]

@@OffGridGarageAustralia I dont know. I guess its charging some caps internaly, what happends when they wont discharge into the grid? There should be some kind of feedback loop? A smps is stupid as well, even less "smart" but it wont push voltage into a nirvana, or it pushes itself into nirvana. i guess, i dont know.

[@mornmorn8425]

When it is going high on volts to 275v but no current is running, the voltage drop on the cables will be enough? Grüße!

[@PietjeNL]

Did this, pv inverter on ac side. Hybrid inverter and to test i shut down the mains. Well the hybrid inverter did not like it, and on the phase the pv inverter was on it the hybrid inverter was shutting down the power to the phase. And this kept happening. Probebly the hybrid inverter switched of for high voltage, but there was no error message at all. But was to scared to keep trying 😂

[@OffGridGarageAustralia]

Oh, wow, thanks for sharing... and trying, I guess. That is what I was expecting as well, an increase in output voltage until one device shuts down.

[@mornmorn8425]

Some generators could actually spin up, but i thought they are very old tech from the 60s. But when there is no 50hz it shouldnt work, so no way. The victron shouldnt create a 50hz net for exporting when there is no 50 hz from the generator, or does it.

[@GapRecordingsNamibia]

I just need to clear up some confusion here, There are people commenting without really comprehending what the setup is here. 1: this is not a grid connected system, this is off grid. The "grid" connection you are seeing is a second 3kW inverter. 2: There are people still raving on about charging to 100% SOC. Let me break it down for you so that you can see what is going on with the supposed 100% SOC. "Why do you insist on charging to 100% when all the manufacturers say for longevity it should be 80 - 20% DOD for daily cycling & max cycle life....." Because, 1: he is not charging to 3.65V / cell 2: He has proven in past videos that charging to a lower voltage and using the absorb function the batteries can be charged to "100% SOC" at 3.45 or even 3.5V / cell. This means, even less stress on the battery poles inside the battery....... I urge you to go back and look at those videos. My batteries are at 100% SOC when my pack (15s) is at 53V (3.53V/cel) and empty 0% SOC when my cells hit 43.5V (2.9V / cell) compare that to the rated 3.65V / cell when the manufacturer says the cell is at 100% SOC or at 2.5V / cell when the manufacturer says the cell is empty, doing the maths should help you to realise that these cells are NEVER being charged to the manufacturers 100% SOC or discharged to the manufacturers 0% SOC.....? I hope this clears up some of the confusion going on in the comments.

[@danielardelian2]

The manufacturer's charge to 100% SOC at 3.65V is done with a high current (typically 0.5 C) and a cut-off limit or tail current to completely terminate the charging process (typically 0.05 C-rate). But the manufacturer's 0.5 C high charging current elevates the cell voltage and that's why the cell must be allowed to get up to 3.65V in their test. If you charge with 0.2 C up to 3.45V and then do a one-hour absorption, there's a very good chance that the batteries will be charged very, very close to the manufacturer's definition of 100% and you have gained nothing regarding the cycle life.

[@GapRecordingsNamibia]

You've tested it to be so? Yes? My batteries remain at a cool 31C in 37C ambient temps when charging as I described, but, when charging as you suggest my temps get to almost 55C, you think that is healthy for those cells? You are aware that dendritic growth is sped up at higher temps and higher charge rates? No? Also, doing an hour or half hour float gives you balancer time to work, my cell difference is 30mV when peak charging and 100% SOC is reached..... Charging as you state leaves my cells at a200mV difference.... But, to each his own, you charge your batteries as you like, I'll stick with what I see happening inside my cells and the SOH of my cells...

[@danielardelian2]

@@GapRecordingsNamibia I did not say that is how I charge my batteries. I only said that if you charge slower than the manufacturer's official capacity test, you still reach the same 100% SOC, but at a lower voltage (3.45V). And we've also seen proof of this in Andy's videos.

[@GapRecordingsNamibia]

Ah, I understand what you mean yes.

[@OffGridGarageAustralia]

Thank you for your comprehensive summary of some of the points, viewers have commented here, @GapRecordingsNamibia Charging to 3.45V with absorption time is 99.6% of the achievable capacity. It takes lower voltage, lower current and lower temperature but more time to achieve that. If it is indeed healthier for the cell, we don't know for sure but we have good indication that higher voltages in Lithium batteries reduces their lifespan. Charging with 0.5C is rarely possible with solar but very much depends on the overall system design. I don't think it is an desirable approach anyway.

[@wazneh]

No where, check the temperature of the solar panels, you wil find they became cooler bcz they are not producing power when you don't need it

[@dama054]

Probably boiling your capacitors in the multi plus

[@volodumurkalunyak4651]

Wrong. If multiplus cant change output frequency from having power at it's generator input, it will dump all extra power there (basically that input is directly connected to the output via relay) If there is an actual generator there, it will reduce fuel usage to compensate (or frequency will increase till solar inverter throttles enought if there is enought power to spin generator with an engine). Having inverter instead of a generator: it will charge the battery untill full and then increases frequency itself / blows up / shut down. After that multi plus no longer has any power at generator input so it can raise the frequency running by itself.

[@dama054]

@@volodumurkalunyak4651 very interesting

[@OffGridGarageAustralia]

Good point with the lower fuel consumption with a real genset. The Phoenix inverter cannot charge its battery though.

[@volodumurkalunyak4651]

@@OffGridGarageAustralia on the video multiplus eventually reported negative power consumption on "generator" input - essentially it allowed power from grid-tie inverters to go there (into Phoenix inverter, 200-250W If I recall correctly). Therefore Phoenix inverter must have charged it's battery at that particular (probably short, at least coule of seconds) period. What would happen if batteries were full (+ BMS cutoff on either cell overvoltage or pack overvoltage) - Phoenix inverter would either shuts down (on input overvoltage) or blow up or increase output frequency (forcing grid tie MPPT's into reducing power or even shutting down) - I have no idea.

[@PlexMulti]

Yo

[@OffGridGarageAustralia]

🥈

[@awo1fman]

You're making an incorrect assumption about the generator. If the system thinks it's the grid, it WILL backfeed power into it. And just because it's turned off doesn't mean it's incapable of sinking power. While generators are often protected from surges and other anomalies, they are not usually designed with the idea that they will be connected to lines that are live and trying to feed power into their outputs. If you're not attempting to feed too much power backward through it, it may be alright, but if you try to feed several kilowatts back into it, I would expect bad things to happen. This is an issue that I've seen addressed on wind systems by having huge resistors set up as a dump load into which surplus power is diverted. I have often wondered what happens to solar panels (or more specifically, an array) that are in full sun but are disconnected from all loads. Does it degrade them more quickly or risk damage, or is it nothing to worry about?

[@devonvankraft]

When the battery is full.. Andy will buy more Bitcoin Miners… and prepare for the next Bullrun. At that time, Andy will buy 10 more Tesla’s with bidirectional charging to power 100 more extra Miners.

[@OffGridGarageAustralia]

There is no end to this spiral of buying more stuff... 😄

[@paulcurtis5496]

Like# 67

[@paulcurtis5496]

System overhead?

[@OffGridGarageAustralia]

Tomorrow, Paul, tomorrow... 5am AEST. Or Sunday...

[@paulcurtis5496]

@@OffGridGarageAustralia the suspense... my Growatt does the same thing and I have no other "grid" source... How do you measure what the inverter is consuming? I "inferred" it as I have no idea how to actually measure it's consumption... Impatiently waiting until tomorrow...

[@OffGridGarageAustralia]

@@paulcurtis5496 consuming in terms of self consumption of the inverter in standby?

[@paulcurtis5496]

@@OffGridGarageAustralia self-consumption across the board, to power itself, perform its duties whether in standby or running. I'm not sure how to accurately measure this, but I do see it in the way you were seeing it. I'm not connected to any other power source other than the sun, when my battery is full the solar provides more power to the inverter than the load - so where is the excess power going? I've always thought it was being consumed by the inverter itself. This consumption varies between 80-200ish watts? I just don't know how to accurately measure this, I can only subtract the load from the incoming solar. Well and some amount is lost to waste, resistance, heat, all of the transactions between components, poor solder joints, insufficient wire size or material, etc.

[@flatfoot]

Put 4kW of ac coupled DC & you'll get a definitive answer...

[@OffGridGarageAustralia]

I'm a bit too chicken doing that, hahaha. But yeah, that will teach us, right!? 😂

[@reginaldpotts2037]

The excess power from the micro inverter is just being dispersed as heat through the circuits, it's not much until the sun shines direct then you might see a BOOOOM. Why do you insist on charging LFP battery to 100% when all the manufacturers say for longevity it should be 80 - 20% DOD for daily cycling & max cycle life, this includes the Tesla.

[@GapRecordingsNamibia]

"Why do you insist on charging to 100% SOC....." Because, 1: he is not charging to 3.65V / cell 2: He has proven in past videos that charging to a lower voltage and using the absorb function the batteries can be charged to 100% SOC at 3.45 or even 3.5V / cell. This means, even less stress on the battery poles inside the battery....... I urge you to go back and look at those videos. My batteries are at 100% SOC when my pack (15s) is at 53V (3.53V/cel) and empty 0% SOC when my cells hit 43.5V (2.9V / cell) compare that to the rated 3.65V / cell when the manufacturer says the cell is at 100% SOC or at 2.5V / cell when the manufacturer says the cell is empty, doing the maths should help you to realise that these cells are NEVER being charged to the manufacturers 100% SOC or discharged to the manufacturers 0% SOC.....?

[@reginaldpotts2037]

@@GapRecordingsNamibia So what your saying is go ahead and charge to 100% and discharge to 0% because in reality that is 80% & 20% respectively??

[@GapRecordingsNamibia]

@@reginaldpotts2037 Did I say go ahead and do that? As our BMS's have been set up, this is how we can do it. We have set up our BMS's to react in a certain way they are not set as from factory, if you are unable to understand that or, you assume that, then that is not my problem now is it? Did I say discharge to 0% SOC? Or did I say if you do the maths? Not only that but how do you figure I'm hitting 0%? Hmm? If 2.5V / cell is 0% according to the manufacturer and I'm stopping my discharge at 2.9V / cell where do you get 0% SOC from at 2.9V / cell? I said that is 0% for how my BMS is set up, a good ways off of the manufacturers 0% No? My inverter cuts out at 45V way ahead of my BMS getting anywhere close to cutoff....

[@OffGridGarageAustralia]

There is no 80% with LFP batteries. Charging to 3.45V is 99.6%SOC as we have tested.

[@reginaldpotts2037]

​@@OffGridGarageAustralia Of course there is 80% SOC you have to keep lowering the charge set point until you find it, after the battery has rested for couple hours 53V for 16S or 3.31V per cell.

[@abhishekkushwaha2455]

🤣🤣🤣🤣 interesting

[@OffGridGarageAustralia]

Especially when the thunderstorm stopped me testing further...

[@slimanus8m]

Are you really mining bitcoin of was it a joke? What's your setup? output?

[@OffGridGarageAustralia]

At the moment I do. It's part of some testing when I have surplus of energy. I'll make a video abut it to point out what I found...

[@Full-of-Starships]

​@@OffGridGarageAustralialooking forward to that one one

[@slimanus8m]

@@OffGridGarageAustralia We are all waiting for it :)

[@NoiseSHome]

This is a click&bait trap. Not the most subtle one I’ve seen but hey, we all like the guy so let’s play stupid, everyone 🙃 In the last seconds of the video we clearly see the MINUS on the “grid” (Phoenix) side of the MultiPlus. So MultiPlus is pushing energy into “the grid” aka “generator” aka Phoenix. Well… what this “pushing” means in the first place? How the micro-inverters are “pushing” energy? There is the key. The voltage will raise only so much, then the micro-inverters will limit themselves not by frequency meaning but by micro-grid allowed voltage (that is not 275 Volt, no). However, nobody’s talking about the elefant. We clearly see the “minus” power on the grid/gen/Phoenix side. 🤦‍♀️

[@OffGridGarageAustralia]

The negative figure is just a calculation. If you look during the day, it always says -1300W or whatever. This is the power coming from the AC-Inverter charging my battery. The Venus OS just does not show it correctly because it's a custom built setup using a Shelly switch to read the AC-Inverter power and displaying it in the VRM. As there is nothing connected to the AC side of the system, it assumes, the energy must go back to the grid. Even there is no grid.

[@NoiseSHome]

@@OffGridGarageAustralia don’t you have a Phoenix on the “grid” side? From other comments, i understand you do.

[@hummmingbear]

Well that was a dissapointing video! C'mon, test it!

[@OffGridGarageAustralia]

Luckily no 💥

[@Taxman_Watchman]

This "-260 W" load goes into the 50 Hz grid creating "Emergency power generator" wich is connecting to the AC in of the multi. This energy heats up the EP generator until it is damaged. Maybe the multi could be damaged too. 🥲