All 3 on one site. It has been paired with 36x Deye BOS-GM5.1 (5.12 kWh / 100 Ah) batteries. B0S-G (solar-europe.co.za)
I don’t know the panel capacity. If the installer’s still around tomorrow, I can get you details if you’re interested.
Thanks @JN.V the aircon unit feeds the whole house with individual controls in each room. So while its Max Current Rating Is 67A, Nominal is 33A and probably a lot less than that if we are only running one or two rooms. I have a Tesla Powerwall at my current house that powers all essentials plus our one ducted, single phase aircon unit (3 rooms) - although we have to be careful to have very little else running when we use the aircon due to inrush current. The Tesla has a 7kW inverter and we probably draw on average 4 kW. I’m not expecting to draw much more than that during loadshedding in the new house which has the advantage of LED globes and more modern appliances. So, around 40kWh of battery should be sufficient by my calcs.
Wow @ebendl that’s three times the size I was considering, and I’m worried about being the guinea pig ;). Please keep me posted.
You need to just consider the current draw from the batteries when you have the aircon on. Even if they market lithiums as “1C” they really should be doing 0.5C max 99% of the time. If you put 40kWh with a 50kW inverter, it is possible to push them to 1C or even beyond depending on the demands of the house.
Is it really necessary to do the aircon setup as you have it? I assume you’re doing a ducted solution. Is it not possible to only put some of the cassettes on backup and get away with a much smaller inverter?
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What aircon are you planning on installing?
I have a daikin vrv with 5 evaporator units in rooms and 1 duct in 1 room. Power draw isn’t very high but I haven’t tried all on at the same time. This is a single phase unit though.
Do you really need a 50kw inverter though?
@jykenmynie that’s a good point re the battery spec, but I really don’t expect the aircon to draw that much power if only cooling a few rooms. As mentioned previously, we currently manage with a Tesla Powerwall which has a 13kWh battery. All evaporator units in our new house will be powered by a single condenser, hence the 67A Max Current spec which I believe should cover the inrush current. Nominal is 33A and I expect to use way less than that if most rooms are off during loadshedding.
Will do, but it I’m not involved in the spec or installation - just a bystander. But still, I go there every day, so if they struggle I’ll know.
@Vassen, I am installing a Samsung DVM which is similar to Daikin’s VRV system that you have. It is a 3 phase unit though. See my response to @jykenmynie above - I agree that it will likely draw much less than Nominal Current when only running a few rooms. I would expect no more than 2kW per average size room.
I mean Quattros have been around forever and have a strong history behind them. How long has the SunSynk/Deye 50KW been around for?
@calypso, that’s exactly my dilemma. As mentioned previously I’m weighing up the “3 times as many things to go wrong” (I would need 3 Victron inverters) and obsolescence risk if one of them fails down the line, with being a guinea pig for Sunsynk. Being a tech guy I’m always cognisant of the old saying “nobody ever got fired for buying IBM” … and look where they are now. I believe (but I’m no expert) that the Sunsynk HV and HF technology is the future for this type of application. I also understand that Victron is working on something similar for release later this year, but can’t wait that long.
To summarize, you intend to use a 40kW aircon at the minimal output during load-shedding powered by 50kW of inverter using a trickle of its capability. The only requirement for a 50kW inverter is actually to switch it on. After that, the aircon will idle.
If it is too late to re-examine this mega central a/c unit, don’t throw good money after bad.
A better solution is not to start that behemoth at all. Just get additional 1ph a/cs just for the rooms you intend to co-habit during load-shedding and power them with a sensible 1ph inverter and keep the change.
You could even repurpose your Tesla power wall for this duty.
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I guess you just need to work out what is best for you. I just know of a mate who was in a similar situation. He started with SMA (3 x 15kw) and then moved to Victron Quatto’s (3 x 15kw) and 10 x 250/100 MPPTs. Part of the reason for the change was how easy the Victrons were to work with via Modbus (Also a tech guy). Having a modular system was seen as a benefit.
Thank @Phil.g00 that did cross my mind, but we’re too close to completion now to make those changes. I initially wasn’t planning to power the aircon, so simply move the Tesla, but that failed the wife test 
Well, to me, you want to plant a small tree, but you already have a 10-ton excavator, and this means you now need a low-bed truck. I would use a spade and wheelbarrow even if I already had the excavator.
Splitting hairs about the low-bed truck design is ludicrous.
@Phil.g00 your analogy makes sense. Taking it further though - getting the low bed truck now does future-proof me for when I need to plant a forest. I’m considering the case of having to go off the grid in the event of total Eskom collapse. My thinking is that a backup generator, started by the inverter when the batteries get depleted, would be my best backup solution outside of normal loadshedding. I don’t have enough roof space for the solar panels I would need …. That still leaves me with the Sunsynk vs Victron dilemma though.
I guess the important thing around your system’s design would be what your actual loads look like. If you have 4kW continuous draw at the moment (sounds like it), and you want to be off-grid, you will need more batteries than 40kWh. Probably more than 100kWh. I use around 15-20kWh per day, and 10kWh of batteries (of which 8kWh usable) is too little for me (not if I am conservative, but luckily it hasn’t come to that yet).
I’d still go for the Victron option, just because their design life is much more than that of Sunsynk. It is also a much more robust setup if you want to go completely off-grid. Like @plonkster also said, it isn’t like they are going to take the 15kVA Quattro out of production anytime soon.
Think about it this way, if you want to go overlanding in Africa, for weeks, are you going to buy the 4.5l NA Toyota LC, proven to go for hundreds of thousands of kilometers without any issue whatsoever, or the “latest and greatest” in small, bi-turbo technology, 22inch tyres etc. HF and HV (I assume you meant HV batteries - switch I don’t think the Sunsynk supports - because Victron also does HV MPPTs?) seems like a good option for people in Europe that doesn’t need to go off-grid, but want to get every last bit of efficiency out of their system for a yet unknown number of years. The LF and LV (talking batteries LV here) option seems like what I would want if I’m going off-grid/have an unreliable grid. It is tried and tested technology. Yeah sure, it isn’t as efficient, just like an NA engine isn’t as efficient as a Turbo, but you are going to replace the turbo at 100k km, while the NA will go for multiples of that before it is even considered to be properly “run-in”.
To me, if you are considering actually going off-grid, the aircon design was perhaps a little on the over-the-top and untenable side, but even if you need to cater for it, the 3x15kVA Quattros option gives you the Victron ecosystem, modularity if something breaks, and integration with things like Fronius inverters. Then when you grab your panels, you can consider something like a 3-phase Fronius PV inverter to “sommer” run that aircon for you during the day (which is when you want to run it).
Otherwise, consider “living within the means” of the inverters/batteries that you do get, and only run the necessary aircon units.
Factor in this then too, the “Darker Side” from the angle that few consider in-depth.
When Eskom collapses, banks, shops, farms, internet, and water, all go down with it.
The collapse of society, and I’m dead serious.
Riotes due to pure frustration spilling over in cities and other areas.
… with you a beacon on a dark night to lure the Have Nots to re-appropriate from you, the Have … your panels a “marketing sign” for all to see.
You will also have on “offer” a flatbed to cart it all away. 
Unless you are a full-blow Prepper with all that involves … focusing on just one aspect is planning to fail. I’m talking years of food, water … and the training and expertise to defend it all, within a community.
I agree with the others, having a solar system for an aircon, sjoe.
My 2 cents.
You commented that you don’t have enough roof space for the amount of panels you’ll need, I’m assuming we are talking around 60 kWp of panels here if looking at the 50 kW Sunsynk, that’s like 100x of 600W panels.
in my mind that is a non starter. Yes of course you can run a big generator semi permanently, but that will leave you with one heck of a diesel bill every month. Then you might as well just install the generator and save the well upwards of R500k if not close to a bar you intend spending on a inverter and batteries now, for your future diesel.
I think you need a expert consultant in the field to look at your setup as a hole and come up with some designs for you., take out the guess work.
That’s how I see it too. In the case of total grid collapse – unless I am on a farm where I’m already mostly self-sufficient – I actually don’t want to be self-sufficient. I want to be out of the country, or at least out of the city.
I want to be able to get by if there is a local outage of a few days, which is something I think is more likely, and already reality for many people. Air conditioning is not one of the things I will care about in that case 
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This has been in the back of my mind for quite a while, what if?
At least I’m on a farm, so there’s that.
As long as the bullets is fresh and the knives sharp there will be meat, same with wood for cooking.
Fruit trees and veg garden is doing fine, so skeurbuik sal ons darm nie kry.
Enough battery and PV power to run fridges at least.
The biggest opstical is pumping water, just last week I once again missed out on a huge bargain on a Lister.
When I get my bargain Lister, I know the next opstical will be to store a good amount of diesel.
and around we go.