I am planning a 2 inverter setup - sunsynk inverters that work in master skacecarrs dément, grid tied. Have 15kwh battery fur one. Can I add a second battery to the other inverter easily enough and it work well as a system? ( hope so as it’s a an eBay auction I won!) - not the same sort as first battery
2 batteries 2 inverters
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hwy17
Anti-Solar Enthusiast
Ahem, sir, the correct term nowadays is Primary/Secondary, rather than Master/Skacecarrs Dement.
But anyway, paralleling the batteries and running the inverters off the combined battery bank is usually preferable.
But anyway, paralleling the batteries and running the inverters off the combined battery bank is usually preferable.
shadowmaker
Solar Addict
My two Deyes (=Sunsynk) are working parallel (no com between them, both set to master IRC) with different batts (FLA and LFP). They work together so nicely that I can't understand how's that even possible.
This one has LFP batts, but as can be seen it can charge them with more power than PV available. Grid sell/loads don't add up as there are two other inverters at play too.
Here's the other one producing more than FLA battery (30kWh) can take and thus capable sending power through LOAD-port to the other Deye. So LFP can be charged at max rate even designated inverter isn't capable of doing it. They do this all the time.
This one has LFP batts, but as can be seen it can charge them with more power than PV available. Grid sell/loads don't add up as there are two other inverters at play too.
Here's the other one producing more than FLA battery (30kWh) can take and thus capable sending power through LOAD-port to the other Deye. So LFP can be charged at max rate even designated inverter isn't capable of doing it. They do this all the time.
Hmm... all this new terminology gets my goat; or am I not allowed to say that, being unkind to the genus Capra?.
Not sure primary/secondary would apply when you could, in theory, have more than one "skacecarrs dément", so I'd pick Client/Server. Though of course Client/Server swaps the order around, so in itself is confusing.
But what is next
. Will we not be able to have male and female plugs or sockets? What about motherboard and daughter boards? Will we no longer be able to execute a program or kill one that got stuck in a loop? And surely whitelists and blacklists derived from the inclusion or absence of frequencies of light, and had nothing to do with ethnic races. I'm probably just getting too old, but it seems the media are getting their knickers in a twist over political correctness these days; though I'm probably not allowed to say knickers any more because it's too British-ist .
houseofancients
Solar Wizard
for the sunsynk LV inverters ( especially if they are paralleled ) you NEED to have them both connected to the same battery...
of course you can always add another battery to the same battery stack
hwy17
Anti-Solar Enthusiast
Innies and Outties, I suppose.
houseofancients
Solar Wizard
agreed... screw the politically correct and total NONSENSEHmm... all this new terminology gets my goat; or am I not allowed to say that, being unkind to the genus Capra?.
Not sure primary/secondary would apply when you could, in theory, have more than one "skacecarrs dément", so I'd pick Client/Server. Though of course Client/Server swaps the order around, so in itself is confusing.
But what is next
I'm not in one of the affected groups, and it doesn't have any material impact on me to change a few words here and there. I choose to listen and accept change. Change is hard, but life is pretty good if that's what I'm complaining about...I'm probably just getting too old, but it seems the media are getting their knickers in a twist over political correctness these days; though I'm probably not allowed to say knickers any more because it's too British-ist
schmism
Solar Addict
As Houseoffancients said, I am not aware of any inverters that offer load sharing (parallel operation) that can do that without an interconnect and common single battery used between all inverters that are load sharing.
2 (or more) inverters, with 2 or more batteries = 2 or more independent systems.
shadowmaker
Solar Addict
Is there a reason why you need them paralleled as Master/Slave (=com cable between inverters needed)? Parallel installation like mine without com cable allows you to use different batteries with each inverter. Closed loop communication with different style (15S/16S/BMS) LFP batteries can be achieved this way and this is exactly how mine were connected last winter. It worked so nicely emptying smaller LFP always first thus leaving room for charging capacity next sunny moment.
Now with FLA connected to other one and LFP to other it always empties LFP first which is really good for FLA longevity (as FLA doesn't like to be empty and wants to be fully charged occasionally).
Don't know about load sharing but at least charge sharing is an everyday phenomenon in my system. It seems to be able to share something like 3kW charging power max. At least I haven't witnessed more. This all started when I connected LOAD-ports to a common ground cable to feed my main panel if grid power is lost.
In my system you need to adjust both inverters individually if needed. But then you CAN adjust both individually.
It's what Sunsynk recommended! but that was with only one battery.
On language, whilst it can be taken too far (in that if people overreact to it when it's not done deliberately, with faux outrage, I think it's inappropriate), I also think if there are equally descriptive terms that don't embed racism or sexism or patriarchy within the language, then it doesn't hurt anyone to use the alternative language, and starts to address issues in society that some people do find offensive. It takes little effort to be thoughtful and nice, and so why not, especially if it means a lot to some. When one is not in one of the affected groups, it';s easy to dismiss the effect minor acts like this can have.
Re @shadowmaker - I;m unclear about your setup because you say they are in parallel with no comms, but then that the load from one goes into the other.
I guess I'm wondering if I can have this:
with 2 different batteries.
thanks.
shadowmaker
Solar Addict
No. My Deyes are connected as you'd connect one and then just add another one and connect exactly the same. They work as individuals as comm cable is not connected and that's why two different batts are possible. Actually LOAD-port don't need to be connected at all as all the magic happens through 2-directional GRID-port when grid is up. It's just when grid is down when Deye starts to feed LOAD-port only. At the same time my additional ATS (=automatic transfer switch) disconnects my system from grid and connects both LOAD-ports to feed my main panel to power everything while grid is down. When grid is up my LOAD-ports can't feed anything as ATS prevents it. BUT in my case LOAD-ports are always connected to each other and evidently can share power through it.
I know this isn't something Deye or Sunsynk would tell you to do and when I contacted Deye engineers about it they just didn't understand it at all. My Deyes have been working for a year and ~45MWh like this and I intend to keep it that way too. I'm just amazed how well they work together while still having individual settings. It's like they know what the other one is thinking all the time.
Nice diagram
Can you show where your CT clamps will be located. The other thought, from my Solis research is that without some Client/Server comms between the inverters they might not know how much battery power to deliver without exporting to grid.That’s my thought too - so not sure how @shadowmaker ’s setup actually works. Hence my primary/secondary setup hence the need for sunstnc over solis.Nice diagram
Ct clamps - honest answer is not certain - just before consumer units I assumed.
shadowmaker
Solar Addict
I have to confess that I haven't tested off-grid capability with this setup. Black-outs seem to be quite rare now that all power lines are underground and usually only few minutes if they happen. I don't want to test what happens if I turn battery backup on just yet as everything works otherwise perfect right now. I need to wait until heating season is over as then I have more time to deal with possible hiccups. I just need to flip one breaker on to make my backup system to work plus cut grid power to test it.
But in normal operation, both inverters are grid tied and seem to either charge battery, run house on battery or solar, or use grid as required? I don’t understand why, for eg, one battery isn’t discharged to charge the other battery. Or one inverter thinks it should export to grid as it has full battery and excess solar but the other is discharging battery to run house?
houseofancients
Solar Wizard
I run off-grid as much as I can..
Grid here is for backup and send back what I really can't store/use only..
Really works like a charm
houseofancients
Solar Wizard
The inverter need something to sync to, in this case it will be the common batterybank
shadowmaker
Solar Addict
Yes. It's like they have common mind although I know they don't.
Well, that can happen, but it depends on the settings. If there's not enough PV and grid charge is on only with the other batt, then it takes power from the other one, but only if that batt SOC is over a set level. You can easily set SOC level high enough to prevent it.
That's impossible. You always fulfill your loads first and only then it is possible to export if you still have excess power (PV/batt) to do that.
Usually both inverters are set to "zero export to CT" with "solar sell" enabled. This means they don't export battery power and use grid only if there's not enough PV/batt. "Solar sell" on the other hand enables exporting excess PV (more PV than needed for batt charge + loads).
Won't "zero export to CT" do the same thing? It uses grid power only when needed.
