gimme_power

I have monitored it for a few days now.
The combined two packs are 666Ah on common busbar. The interter knows the capacity is 666Ah. The inverter is set to AGM% mode.
The SOC estimated by the inverter is constantly about 3-4% lower than the combined Averge battery packs, reported for the Averge master BMS.
So I recon if I use the Inverter SOC in the timer settings I should be safe enough.

In testing demo mode, working perfectly

My understanding is that it uses the Voltage specified in the Battery settings as the 100% point, and then does coulomb counting down from there by measuring amp-hours exiting/entering the battery and deducting that from the "Batt Capacity" specified.
I ran in AGM% mode for a few weeks as well (whilst waiting for a battery firmware upgrade) and was pretty impressed with the accuracy, although letting the BMS handle it via LiBMS comms it is still preferable since without it you lose communication when errors occur and other features like dynamic charge/discharge rates that the BMS supplies the inverter.
For instance my BMS limits the Max Discharge if one of the batteries in the bank depletes before the other.

Had a setup like yours and now a slight improved one.
Definitely had no issues with the fluctuating load when using the iron/air fryer/hair iron/hair dryer etc.
So to quote you in your words you are being a ninny 🤣
Each appliance is drawing what they need and the inverter is supplying that need from a combo of grid/PV/battery, which is then distributed via your DB, breakers and plug points.

If the only inconvenience is to your eyeballs, I suggest you don't look.
 

@gimme_power,
I can be wrong here, but in my mind, modern inverters - incl. SS/Deye - are transformer less designs, and relies on high frequency conversion from DC to AC.
Your system is slightly beefier than mine, and I use a standard steam iron without issues.
Perhaps this is why they don't like and drastic change in load frequently, e.g. your steam iron. Especially during days of sunshine, one want's to use the pv to supply the load. so if the load disappears (steam iron switches off), the pv can't switch off instantly, and the energy needs to go somewhere. That somewhere is the grid. Even if you do no feed back into the grid, the inverter "dumps" that excess energy into the grid, no matter your disabled feedback setting, so for a few seconds you will see energy going into the grid. The CT coil will not prevent this, because it is also slow to react in it's measurement, so up to a few 100W of power flows (in the wrong direction!)., and the inverter pulls that back immediately to 20W (the trickle feed that allows your inverter to remain synced to the grid).
So, in my view, nothing to worry about, my system is 4 years old. But I would think in the end, an Inverter that supplies constant load with few oscillations, e.g. a geyser will probably last longer that one that has an ever changing load. 
Hopefully the real gurus can also elaborate / explain this better, so I can be better informed.!
 

I still have a geyser switch in my meter box dating back to the late 70s that allowed the council to do exactly that.
 
 

I bought 32 of those SVolt 184Ah cells earlier in the year. So need to get them assembled. I currently have 3 Averge 48100S packs
 

There can only be one - Noordkaap, hands down...

It really  makes a lot of difference if you home al the time. This is why we can run offgrid.

Thanks, yes I got an email from them as well. I can confirm it worked for me too.
😄

Haha, yes you are right, but I am 10 years out so will have to stick with a helper for now 🙂  On a normal summer day I have no problem at all.  I am doubling my battery capacity with a diy battery build over the holiday so that will leave max 5% of days where I need any grid at all.  Not days like above though.

Hi @VirWat thanks for the reply. 
1) I like the suggestion about moving the main grid MCB but then, as I understand it, if I switch over to grid side (on switch over MCB), and I want to remove grid from the two inverters I need to isolate them individually (one by one).  If you say the breaker 'must' be moved, is this a regulation or guideline somewhere?
2) The reason I have those parallel breakers (main grid in and main load out) is because of a video of Keith of Sunsynk about paralleling inverters. He said that Grid, Load and Battery should always be switched together.  Not sure I misunderstood what he said.
 

I am having the same issue. Did you already report it to the SolarAssistant Team?

I just uploaded a version I had lying around on my PC to the downloads section on the forum here:
 

Well done! I have 4 packs of LEOCH 48100TB from Averge. Look similar to yours, front layout somewhat different. Running now for more than 3 years. Cycle counts are: 1074, 979, 890, 765. All show fairly balanced cells, no issue. Except that the last one purchased has significant lower internal resistance, it discharges and recharges faster than the others. But at full charge they equalize.
I use the PmodbusToos to monitor them. The RS232 from "master" to computer did not work. So Averge delivered a RS485 adapter and that upgraded software, now it works. The RS485 works like a serial data bus between the packs and the computer.

Three months on and so far so good. All three packs have balanced cells, all of the time.
 
Another issue I had was resolved today with a firmware update for the Averge 48100S.  The master BMS now reports the average SOC for the bank.  Previously it reported the highest pack SOC when charging, and the lowest pack SOC when discharging, which sometimes lead to continuous charge-discharge-charge-discharge switching when using the Sunsynk timer to charge to a certain SOC and hold it there.
So with these two issues sorted I am hoping for a good 3500 cycles out of them... I am nearing 100 now

Three months on and so far so good. All three packs have balanced cells, all of the time.
 
Another issue I had was resolved today with a firmware update for the Averge 48100S.  The master BMS now reports the average SOC for the bank.  Previously it reported the highest pack SOC when charging, and the lowest pack SOC when discharging, which sometimes lead to continuous charge-discharge-charge-discharge switching when using the Sunsynk timer to charge to a certain SOC and hold it there.
So with these two issues sorted I am hoping for a good 3500 cycles out of them... I am nearing 100 now

I run two Victron multiplus 2 5kW units in parallel. In the Victron guide for parallel setups they stress the point that your DC cables running from a busbar need to be of equal length. BUT the also state that your AC cables need to be of equal length as well and NOT be over sized. There needs to be a bit of resistance on the AC side for the units to correctly operate in parallel. 
I know you have 2x Sunsynk units but maybe this can help.
To quote:
Warning against over-dimensioning the AC wiring
Note: Do not over-dimension the AC cabling. Using extra thick cabling has negative side effects.
Technical background: for a properly working parallel system, the AC current should be evenly distributed between the paralleled units. The resistance in the cabling helps with that and is needed for that; to overcome small differences between one inverter/charger and another, for example in the AC contact on the AC input. When the resistance in the cabling is too low, such small differences in resistance of the current path in a unit itself can results in a large relative difference. This results in bad current distribution.
An exaggerated example:
Using 2 units (A and parallel and using too good cabling, one might achieve a total resistance for Unit_A of 0.0001Ω and a total resistance for Unit_B of 0.0002Ω. This results in Unit_A carrying twice as much current as Unit_B. Using the same 2 units in parallel with, for the sake of this example underdimensioned AC cabling one might end up with a total resistance for Unit_A of 15Ω and a total resistance for Unit_B of 16Ω. This results in a much better current distribution (Unit_A will carry 1.066 times more current than Unit_A) even if the absolute difference in resistance is much bigger than in the previous example (1Ω vs 0.0001Ω). A side effect of over dimensioning the AC cabling can be faulty Power Assist operation. Out of all units, the phase master is in control and measuring the AC input current. And in case that current is (grossly) unevenly distributed between the paralleled units, the resulting total AC input current can end up being too low (under charging the battery).
https://www.victronenergy.com/live/ve.bus:manual_parallel_and_three_phase_systems

Hi all solar experts,
I need your insights please. I have noticed, what seems to me to be a big problem on my setup. The master inverter sometimes seem to do +-90% of the work while the slave idles at +-10%
 
My system:
- 2x Sunsynk 5kW in parallel
- DC cables go to common busbar via two Keto 125A disconnects.
- DC cables exactly the same length and internal resistance from busbar to inverter is near equal.
- 4x Strings of 5 JA Solar 545W panels.
- All string panel orientation is exactly the same
- 2 strings connected to master inverter (MPPT1 and MPPT2)
- 2 strings connected to slave inverter (MPPT1 and MPPT2)
- 3x Averge 48100S battery packs (they are 15 cell packs)
- All connected to common bus bar, battery cables same length.
 
Operation:
- The inverters are ‘priority Load’
- Work mode is ‘Limited to Home’, although I have nothing on ‘non essential. (discussion for another day but this is due to Sunsynk software bug where import and export of secondary inverter is not added if set to ‘limit to load only’)
- My batteries are setup to operate on Voltage, no battery communication. Reason being that one of the three packs discharge more easily and it presents a problem when SOC is reported to the Inverter. (discussion for another day). I am happy with the battery setup as it is at the moment.
 
The problem:
- On a normal morning the batteries are low and gets charged back up from solar. When full the solar production is clipped/reduced to satisfy the load only (Pic1)
- When this happens it seems:
- Solar production of master inverter is maintained to satisfy the near total load (Pic4).
- Master inverter produces half of the AC load, but also exports power to the battery, as if charging the battery(Pic2). This DC current does not go to the battery because the battery is full. It flows back to the slave inverter via common DC busbar (direction of current confirmed with clamp meter).
- Slave inverter solar production reduces to near zero (Pic5). The slave produces half of AC load, but it looks as if it is using battery. In fact it is using DC flowing from the Master inverter via the common busbar (Pic3).
- When this happens the master inverter can work much harder than the slave as in the pictures. These pictures were taken at a different time so the whattage will not correspond to the graphs, but it is showing the same.
Pic6 – Master inverter Overview showing it is producing 4500W
Pic7 – Slave inverter Overview showing it is producing 300W (massive difference from Master inverter at the same time)
Pic8 – Master inverter Flow Chart showing 4000W solar production and current flowing to the battery (but actually flowing to the slave via the busbar)
Pic9 – Slave inverter Flow Chart showing 500W solar production and drawing 1800W from the battery but in fact it is coming from the master inverter.
 
Big Question:
- Is this normal behaviour in a parallel Sunsynk setup? Somehow I doubt it because over the life of the install, the Master will work much harder than the slave.
- What can be wrong?
- Can it be that the MPPT’s in the Master is not balanced with the MPPT’s in the slave, in that it senses/produces power at a different DC voltage and as a result there is a flow backwards to the slave?
- I doubt that it is caused by a difference in the internal resistance of the DC circuit from the common busbar to the inverters. I have taken great care when making up the cables etc.
- This only happens if there is surplus power on the panels. As long as the DC has somewhere to go e.g. into the battery, or fully exported to the grid or load, then this scenario does not happen.
- My current ‘solution’ is I have switched one string out from the master and one string from the slave. In that way everything is nicely balanced, although I have too little power at times.
 
I would really appreciate your input on this, technically or from experience, or otherwise.
 
Thanks
PS: Seems the pictures were uploaded in reverse order.
 

Hi
Do you have a manual for the batteries that provides info on the parallel communication for the RS485 ports? 
We'd like to confirm they are correctly talking to one another
[EDIT] Normally COMS#1 goes to COMS#2 for master slave communication, for instance RS-485-1 => RS-485-2(Please verify with manual)
Please ask the technician to wire your terminals correctly, the battery on the right might take more load than the one on the left

Cheers
 

Some of these active balancers have place for a switch and it is just shorted on the board
 
Putting a switch on it and leave the active balancer inside the battery and just have a switch to enable active  balancer from time to time when in the steep section of the soc graph not all the time
I have a shoto server rack battery  with one bad cell that always drifts 
I soldered two wires to this cell routed through a hole to the outside of my case to a quick connector
 
When this cell has drifted i manipulate this cell by connecting a charger to this quick connector or add resistance if i overshoot the charge

How can you have a reading of 3.323V yet the BMS gives the minimum value 3.543V for the lowest cell. 

My instinct tells me the 2 different directions should be on 2 separate strings, one in each of the MPPTs. I don't suppose you could build a frame facing north?

Attached is a schematic copy  of the current design :
 
BRG_BMS_gateway_1xB.pdf
 
I think it doesn't get simpler than this , apart from the isolated dc-dc power supply , which in any case is a low cost MornSun module. I have never worked out a bill total , but will be surprised if this goes beyond R300-00 , excluding enclosure .