HB integration into system

[BlackwaterPark]

So I've got an existing system that I want to expand and I'm filling you get some clarity and advice into how to proceed.  the current system is:

2.7kw of pv running into a classic 150 (9 panels..3x3@70-ishV

2 Kilovault HaB batteries in parallel, total of 15kw@48v

A Genetry solar GS6000 inverter (a kind of custom made LF unit) that is not capable of any comms.

An EG4 Chargeverter (100a 48vac charger)

These all are connected to a pair of Victron bus bars, 4 post 600a, 70v, and the Invertor goes through a midnite breaker box before hitting the bus bars.

I want to expand both the PV input and the battery storage. Kilovault went under last year, so I've got to source other batteries, and i'm wanting to switch over to midnite gear entirely anyway, over time.  So I already have a Hawkes Bay 120 and the companion breaker box, which is not deployed as of yet. I've got 16 Sirius 410w bifacials on the way, which should bring the HB up to its rated wattage.  I want to double my battery at this stage, and then add a like amount sometime over the summer.  And for this, i'm looking at the Powerflo server units. So, a few questions...

given the system already in place, can I simply tie both the Hb and the new battery back into the same bus bars? This is all open loop on the battery side.  Should I approach this another way? The bus bar posts are full up...should I add another set, and connect the bars?

So far as the existing batteries go, when I had communication with kilovault, they told me that it's best to charge those units up to 56.6 and hold for five minutes, as this is where the cell balancing takes place. I'm to understand that falls within the powerflo capabilities.

Two, I heard that the a HB can talk to the batteries now with the new firmware update...does this also need a midnite inverter (or at least an inverter with coms) to facilitate, and if not, can someone tell me how that all works? 


And lastly, and this is in unrelated to my system question...A friend asked me to get a system put together on the relative cheap, and wants the EG4 6000xp. I wanted to see how well the powerflo can communicate with that unit...I know they use pylon, and I was told by a rep at current connected that it's like trying to use linux on a windows pc. I'm not a computer guy, but I was getting the sense that although it *could* work, it might just be more headache than it's worth? Can anyone speak to that here?
 

[ClassicCrazy]

The Hawkes Bay and Barcelona will do closed loop communications with batteries on the Pylontech protocol .  Regarding how all these charging setpoints work when in closed loop it is hard to know exactly  and I have been trying to find out. Different charge controllers do different things . I haven't ever seen anyone publish an order of operations for their inverter/ controllers on how they work exactly. And all that can be one firmware update away from changing some of that.
Regarding your Kilovault batteries . It really depends on what the particular bms is programmed for . On my batteries which have a Pace type bms I can program it to start balancing at 3.4v percell and a 20mv differential between cells. The SOC will go to 100% at 55.2v when it drops to 5 amps of current ( this is for a 48v 300ah battery) . In addition it depends on how much current the cells will balance at. For a passive balancing bms there are resistors that shunt off current on the high cells . Usually this is only 150 mv or so . My battery also has an active balancer on it which will move 4 amps current from highest cell to lowest cell. This happens at 3.45v per cell and ends at 3.4v per cell and will balance down to a 5mv differential.
Of course in a lot of normal use most batteries  the cells are all within 5 mv of each other until they get to around 90% full so balancing doesn't really matter in that part of the curve where most power is used .
If it was me I would just parallel the Kilovault with the new Midnite batteries and charge to the same setpoints for the midnite batteries since they probably close enough .
The Midnite batteries are communicating with each other if you get more than one - in that they will adjust their current or voltage to each other so they are close to the same when charging.
The EG4 6000XP should work fine iwth the powerflow batteries since you can set the 6000xp for pylontech protocol input. But you can also just use open loop charging ( they call it lead acid mode).  I have a 6000xp and my bms programmed to pylontech but so far only using the open loop mode ( same with the Hawkes Bay I have ) since I don't understand exactly how they work in closed loop. I think some of it depends on how the setpoints in the battery bms is programmed and that I am going to experiment with since my battery bms lets me change whatever I want in it.
Most people just plug and play all this stuff, trust that the manufacturers know how to do it best, and then don't pay too close attention to the nitty gritty details as long as they get the power they need out of the system. And if the system is designed with some extra capacity you don't get into the zones too much where moderate out of balance batteries make too much difference .
Larry 

[BlackwaterPark]

Thanks for the reply and information, Larry. I have a tendency to overthink things, so I think i'll just run it as such like you say.  I'll be looking forward to switching over to the rosie this year as well and i think then i'll repurpose some of these existing sudden components to a secondary system, maybe a dedicated shop system or something. Having all midnight gear should take take the guesswork and thinking out of the equation. and make everything look cooler to boot!