No, I think all three are in parallel. But the two on the left shares a cable, while the one on the right has the same thickness cable but doesn’t share. That means that relative to the battery capacity, the right side has double the cable thickness, and that means that one is going to work harder. Its SOC will drop lower in the evening, and it will recharge first during the day. Depending on the extent to which the BMS interferes with charge currents, it could leave the two on the left partially charged.
Ok see if I understand this please.
Two on the left shares a cable, so more resistance for the amount of amps they can/will deliver through that cable.
On one the right has the same size cable but does not share with any other battery, so a lower resistance for the amps going through its cable?
So you’re saying the the left bank will work harder?
Our friend Andy has proven that with the mega battery bank he as with the variable set of capacities, etc. Let the BMS’s (lots of them) deal with them he says… 
Andy does have updated vids after months … those 3 banks of his, yeah, he had to do some investigation as they did not behave the same as he expected in the end. The 3 x different BMSes did not perform as expected … rather big discrepancies between them.
At least, that is what I saw in his vid on that matter, when he “pulled them apart”.
My takeaway … better the cables, the BMS make/models, and the settings are identical … down to the nth degree.
We are working with mA and mV to balance and keep the cells/banks in line over YEARS.
His issue was more a poor BMS and balancer setup BUT that’s what he was testing. If you have an excellent BMS and Active Balancer (set up right) then no matter what battery size cables, etc you will be fine.
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True, but in this particular thread that idea is not even a possibility. DIY, whole new kettle of fish.
Louis the other day made me aware of that when we spoke of balancing, I can adjust mine, brand name warranty banks not so much, different rules/solutions.
Hey man… I’m trying to derail the thread… Come now
Work differently, not perfectly in conjunction with the right bank, in a subtle way that will affect it over time as per Jaco.
The solution is simple, as posted before. No need to panic. No harm done. You have foresight.
I think the one on the right is going to work harder. The two on the left each contribute 50% of what goes over the cable, the one on the right contributes 100% of what is on that cable. Cables are the same size. The larger capacity of the combined two on the left does mean they will tend to contribute more to the total, so I cannot really say what will be the larger factor here. But it will divide unevenly.
I suspect it will be similar to my case. The lower Ri of the left bank will cause it to do many small discharge/charge cycles as it delivers more than it’s share of current under load, and then rebalances afterwards.
The etower stack react on a single high or low cell that will send a “Stop Charge / Discharge” command based on the single cell value, stopping charge before balancing and stopping discharge way before “Bottom balancing” can happen while the grid is there to support the load. You can only discharge them to almost the same value if you remove the grid and allow the battery to pull way down. The imbalance starts and over time just gets bigger and bigger making it impossible for the not so clever bms to fix.
Hope my layman’s term explanation makes sense to all the engineers around here.
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It would be interesting to see which of the stack is battery 1 (It has lowest /highest voltage cells and also lowest/highest temp cells) - Maybe it’s bottom right? 2x comms cables?
Bottom right has the can cable and bottom left only one RS485 cable. Looking at that, 1 = Bottom right, 2 = Top left and 3 + Bottom left. But all depends on the dip switch settings.
You guys have made me so scared now, I made more debt. 
But this is it, finish and klaar!!! I draw the line now in the cement.
Sorry for only posting now, as luck would have it I have been without internet for almost 4 days and the Open Serve guys only fixed the problem now. This is also why we could not tend to the router reprogramming yet. This now must wait until next Tuesday.
But I will be fetching my new battery this afternoon still.
@JacoDeJongh , please tell me how I must ensure what cables goes to what sides/poles of which batteries. The installer is coming back tomorrow.
I want to make sure his view alligns with yours.
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You had a plan, your plan was good, installer prepped for that … so you just moved earlier on your plan, and that is good too.
Now use them to recoup that cost, and you are sorted for years to come … once you have the exact details of how to wire them correctly.
Well done from my side btw. 
Thank you!
I plan to have a zero electricity bill bill from hereon forth. Bigger inverter will see to that now.
Very very impressed with the bigger setup. I have recorded up to 6Kw (previous highest was 4Kw) from my panels and this at before 10h00. The extra 4 panels made a huge difference.
But yes, I am broke now and I still have that $#@ leaking garage roof to sort out.
We had leaking from walls, double story. Water runs down on the inside of the wall.
The paint peeling off, the rails inside are rusting … the floor is wet with every rain.
Cavity walls, what is that … blerrie original builder did not do that.
In any case, first, we had to seal the aluminum frames, yes, expensive quality frames, built like cr@p, leak like a sieve, and installed incorrectly by said professional. The guy who came knew EXACTLY what to look for, and how to fix them. Cost a pretty penny to fix that … he showed me his actual costs. Damn, stuff is expensive today!
Next, sealing the wall … man, 15 people were here … the last guy walks in, 3 minutes in he says “I’ll fix it. If there is no more leaking after 2 rains, then only pay me.” No deposit required either. I paid him with a big BIG smile.
My point … water leaks, can be VERY simple or VERY complex. I knew we were in for the complex one. So I learnt, there are some super clever experienced people out there who can do it one time right … it is a just PITA to find them though … and they give 2 year warranties on their work too.
I have a massive problem with rising damp in the apartments in the backyard of my place.
At the moment, my solution is to wait until the rainy season is over, and then simply repaint. Cheaper than the alternatives, even if it has to be done every year.
But eventually, I probably have to look at something like a liquid damp course treatment. Pretty sure when the building was built – it used to be store rooms – damp coursing was not installed.
Same problem, water flows through the wall … to fix it, yeah, I’m busy “learning” about soil movement and retainer walls and channels and cladding the wall vs panting it … and … and … we are talking big bucks sorting THAT out.
Never take shortcuts when one builds it first … the costs following taking shortcuts make the initial “saving” look like cents on R1000 rand notes.
Cladding (on the inside) … consider that, if you want. Cheapest long-term option for us so far.