Inverters that support high voltage (500v) storage batteries

[Rational]

Either they have proof and manufacture confirms, or they don't ( hint, they don't and won't )

As @Daddy Tanuki wisely writes, and in my words, sales will always response yes to anything you want to get a deposit, that doesn't mean you get a functional product for your selected inverter.

Since you looking to build a copy of my system, do that, otherwise your the engineering team and support and unless you have the knowledge and contacts to make it work, stick with what is proven.

Apologies. Didn't see your response here above immediately after DT's until just now.

It makes more sense to me now why you replied that you were not going to give further input now.

I see I missed the above and my response came across without factoring in your above response.

I'll do that. 'known good' is what I need. Not wishful thinking. Hope you'll continue to reply as I follow in the path you've already confirmed.

It will be awhile though before I buy any seplos hitens.

 

[peufeu]

I appreciate you pointing out that the sunpal x1 is a 100ah battery and the solis S6 is only able to handle up to 50A battery packs.

You're mixing up Amperes (symbol A, the unit of current) and Ampere*hours (symbol Ah, an unit of charge or battery capacity).

Think in terms of flow and stock:

Amps = current = flow = amount of charge flowing per second

Ah = current * time = flow * time = charge = stock

Watts = power = flow = amount of energy flowing per second

Wh = power * time = flow * time = energy = stock

In your Sunpal datasheet it says the max recommended current is 50A and capacity is 100Ah.

100Ah means it can deliver Amps*Time=100Ah so 50A for 2 hours, or 25A for 4 hours, or 1A for 100 hours, etc.

If it can deliver I=1A for T=100 hours at voltage V then that's an energy of P*T = V*I*T, so the energy capacity in Wh is voltage times capacity in Ah. This is an approximation because battery voltage is not constant during discharge.

The inverter's maximum current is 50A, same as the battery, no problem. If the battery's maximum current is higher than the inverter, then what happens is the inverter won't overload the battery, so it is safer. If the inverter's maximum current is higher, then the inverter needs to limit current according to information provided by BMS. This is always required for lithium batteries anyway, near full charge the BMS will tell the inverter to reduce current for the final charging stages. That's why you usually can't set some voltage and current parameters in the GUI and be done with it like with lead acid.

I think Solar Guppy is being too optimistic: the most likely case if the inverter and BMS don't talk to each other is the inverter will just ignore the battery, it won't charge it or discharge it, because it doesn't know what current and voltage the BMS allows. So, safety first: it doesn't do anything lol. But I didn't test on the Solis high voltage so maybe it will do something different.

So about these "industrial blade fuse holders", I'm interested.

1. Would these replace T-fuses? In addition to?

I'm not the industrial fuse guy, but...

- Blade fuses do two jobs: disconnector and fuse, so you need less hardware. A bit like a circuit breaker.
- T fuses use screw mount so you would need separate disconnector
- Always read the datasheets: some NH00 fuses are rated for 1000VDC, others for just 125 or 250VDC
- You can also use a circuit breaker but it should be rated for the voltage and short circuit current, and it should be bidirectional which is a bit of a problem to find

 

[Rational]

You're mixing up Amperes (symbol A, the unit of current) and Ampere*hours (symbol Ah, an unit of charge or battery capacity).

Think in terms of flow and stock:

Amps = current = flow = amount of charge flowing per second

Ah = current * time = flow * time = charge = stock

Watts = power = flow = amount of energy flowing per second

Wh = power * time = flow * time = energy = stock

In your Sunpal datasheet it says the max recommended current is 50A and capacity is 100Ah.

100Ah means it can deliver Amps*Time=100Ah so 50A for 2 hours, or 25A for 4 hours, or 1A for 100 hours, etc.

If it can deliver I=1A for T=100 hours at voltage V then that's an energy of P*T = V*I*T, so the energy capacity in Wh is voltage times capacity in Ah. This is an approximation because battery voltage is not constant during discharge.

The inverter's maximum current is 50A, same as the battery, no problem. If the battery's maximum current is higher than the inverter, then what happens is the inverter won't overload the battery, so it is safer. If the inverter's maximum current is higher, then the inverter needs to limit current according to information provided by BMS. This is always required for lithium batteries anyway, near full charge the BMS will tell the inverter to reduce current for the final charging stages. That's why you usually can't set some voltage and current parameters in the GUI and be done with it like with lead acid.

I think Solar Guppy is being too optimistic: the most likely case if the inverter and BMS don't talk to each other is the inverter will just ignore the battery, it won't charge it or discharge it, because it doesn't know what current and voltage the BMS allows. So, safety first: it doesn't do anything lol. But I didn't test on the Solis high voltage so maybe it will do something different.



I'm not the industrial fuse guy, but...

- Blade fuses do two jobs: disconnector and fuse, so you need less hardware. A bit like a circuit breaker.
- T fuses use screw mount so you would need separate disconnector
- Always read the datasheets: some NH00 fuses are rated for 1000VDC, others for just 125 or 250VDC
- You can also use a circuit breaker but it should be rated for the voltage and short circuit current, and it should be bidirectional which is a bit of a problem to find

Thank you for your kind reply explaining further peufeu. Okay, I kinda thought I circled the wrong thing in the second spec sheet when I circled 100Ah and not the 'recommended 50A' above it to the right on the chart. But didn't want to post again should it confuse things further. I was also trying to get further clarity on Solar Guppy's input on pointing that out as a possible issue to confirm.

But your explanation was excellent for my grasping things. In fact, daddy tanuki spent an hour with me on the phone a few hours ago going over what you just kindly typed up for me. So it's definitely reinforcing things. I'll reread it until I grasp it completely. It's time I nail down this essential knowledge completely to reduce risk and increase my efficacy. Especially as I begin to spend actual money.

Yeah, it seems the SP battery may be fine after all as the spec sheet seems to also indicate 50A is recommended.. But for safety sake I think he's correct that sunpal has not proven they have actually tested and confirmed these two work together. It's just an unfounded claim at this point. My typical nature of liking research and trusting people tend to still allow me to purchase in this type of case and perhaps gain a better price per unit of value for my efforts. But in this particular case the more I think about it, SG is right. My family will look upon me poorly when things aren't plug and play and there are issues and delays or worse.

My daughter said tonight that my son-in-law would feel better about things if we go with a solar company for the main house even if it costs more and doesn't have the tweakability and expandability I had envisioned with DIY. Ah well... He get's a vote for sure of course. This will be my first install and it's probably best to ensure success.

My plan is to still buy an S6 for my other building and make that a learning lab situation. I'll use the Leaf battery pack and Dala's battery emulator and carefully get that working.

DT suggested that once the solar company installs the new system and certifies it on the grid, since we will have separate inverters for each house, I can always swap out the inverter on my side with my own later. Then I would have the ability to add my own batteries from Seplos and tweak the system all in English. That would give me near 100% guarantee of success. Unless somehow the power company would know? Would they? I could always put the original inveter back in place should that occur.

So that's the current plan after everyone's input today.

Thanks to everyone for your time and effort in typing up your responses. I'm grateful.

 

[Solar Guppy]

I think Solar Guppy is being too optimistic: the most likely case if the inverter and BMS don't talk to each other is the inverter will just ignore the battery, it won't charge it or discharge it, because it doesn't know what current and voltage the BMS allows. So, safety first: it doesn't do anything lol. But I didn't test on the Solis high voltage so maybe it will do something different.

So for those that want to use an Solis S6-EH1P(3.8-11.4)KH-US, I will offer the following verified information for your viewing enjoyment:

• Solis S6 requires a compatible High Voltage battery, that is the working voltage, current and BMS communications. The backup port will not turn-on without proprietary BMS communications established.

• Your installation should match the inverter battery current and for the 11.4kW model requires a minimum of 50A and greater than 300V to meet the output ratings of maximum power and surge abilities.

• If you want to parallel inverters, the batteries as not shared ( being non-isolated the voltages varies ) a the battery for each inverter should be the same make an model as the firmware is constantly adjusting power to be shared 50/50 between inverters as an example if there is a two of them

• There is no safety improvement adding another fuse which should be for both positive and negative as this is a non-isolated design. All approved batteries ( and Seplos S4 ) come with breakers built-in and the inverter is fused internally as well.

• For battery choices, here is the Solis approved battery list, if you do not require UL9540 for your installation, there is only one other choice, The Seplos S4. If your looking for alternatives from China based suppliers they do not exist, Solis has provided guidance no others will be added.

Being a retired hardware / software engineer that contributed to products well know in renewable energy since 2022, it was my goal to have all the features of the well known options ( Sol-* / EG* ) discussed on this forum but with a HV battery as even with my experience, building 500+ amp battery banks safely is a very challenging task and the total system costs are lower and net efficiency high with HV.

For those that consider HV batteries are more dangerous they likely over look the PV circuits are identical. My concern with whole home LV battery banks the currents are not something I am comfortable with.

48V batteries inverters came to market in the early 2000's when inverters were in the 1000 to 4000 watt range as the current demands exceeded what lower voltages ( 12V/24V ) could provide. I see is the next transition to 400V for the exact same reasons, but in the end the market will decide this.

 

[OffGridForGood]

For those that consider HV batteries are more dangerous they likely over look the PV circuits are identical.

I would say, no not "Idential" - the energy, 10,000's of amps from the ESS, is not the same as the PV if there is a short.
and the ESS is likely interior located, while the PV is always exterior, except for a pair of cables to the inverter/SCC.
Generally the high voltage PV is set it once and never go near it again, while the ESS is far more accessible day to day, and more likely to be accessed for upgrades/changes/tinkering.
About half the time each day you can count on the voltage from the PV to be near zero.

My concern with whole home LV battery banks the currents are not something I am comfortable with.

I have considered this as well, but the fact remains, 48v DC has far lower potential to arc a small gap than 400v DC, and although 48v is nothing to be careless with, 400v is definitely a lot of potential in the seriously leathal range. Extinguishing a DC arc is already an issue at 48v, I can only imagine what is required to extinguish a 400v DC arc.
- Which leads to the other problem I encountered researching parts for high voltage DC: all the parts required such as bi-directional HV DC breakers seem to be very hard to come by = expensive.
So I gave up on HVDC ESS and instead buy short large diameter cables to connect 48v ESS to Inverters.

 

[ChrisG]

So for those that want to use an Solis S6-EH1P(3.8-11.4)KH-US, I will offer the following verified information for your viewing enjoyment:

• Solis S6 requires a compatible High Voltage battery, that is the working voltage, current and BMS communications. The backup port will not turn-on without proprietary BMS communications established.

• Your installation should match the inverter battery current and for the 11.4kW model requires a minimum of 50A and greater than 300V to meet the output ratings of maximum power and surge abilities.

• If you want to parallel inverters, the batteries as not shared ( being non-isolated the voltages varies ) a the battery for each inverter should be the same make an model as the firmware is constantly adjusting power to be shared 50/50 between inverters as an example if there is a two of them

• There is no safety improvement adding another fuse which should be for both positive and negative as this is a non-isolated design. All approved batteries ( and Seplos S4 ) come with breakers built-in and the inverter is fused internally as well.

• For battery choices, here is the Solis approved battery list, if you do not require UL9540 for your installation, there is only one other choice, The Seplos S4. If your looking for alternatives from China based suppliers they do not exist, Solis has provided guidance no others will be added.

Being a retired hardware / software engineer that contributed to products well know in renewable energy since 2022, it was my goal to have all the features of the well known options ( Sol-* / EG* ) discussed on this forum but with a HV battery as even with my experience, building 500+ amp battery banks safely is a very challenging task and the total system costs are lower and net efficiency high with HV.

For those that consider HV batteries are more dangerous they likely over look the PV circuits are identical. My concern with whole home LV battery banks the currents are not something I am comfortable with.

48V batteries inverters came to market in the early 2000's when inverters were in the 1000 to 4000 watt range as the current demands exceeded what lower voltages ( 12V/24V ) could provide. I see is the next transition to 400V for the exact same reasons, but in the end the market will decide this.

@Solar Guppy
I’m just finishing all my wiring, critical loads panel, etc at my primary home and have not bought an inverter yet. At my cabin I did 6000xp 48v system but feel like I need to embrace the future at home. I can’t sell back to grid in my slice of North Carolina but would highly consider a HV inverter with HV LifePo4 battery (think Soluna was LifePo4). Can you run that Solis in offgrid mode and only use grid for charging and passthrough if needed.

 

[Brucey]

I would say, no not "Idential" - the energy, 10,000's of amps from the ESS, is not the same as the PV if there is a short.
and the ESS is likely interior located, while the PV is always exterior, except for a pair of cables to the inverter/SCC.
Generally the high voltage PV is set it once and never go near it again, while the ESS is far more accessible day to day, and more likely to be accessed for upgrades/changes/tinkering.
About half the time each day you can count on the voltage from the PV to be near zero.


I have considered this as well, but the fact remains, 48v DC has far lower potential to arc a small gap than 400v DC, and although 48v is nothing to be careless with, 400v is definitely a lot of potential in the seriously leathal range. Extinguishing a DC arc is already an issue at 48v, I can only imagine what is required to extinguish a 400v DC arc.
- Which leads to the other problem I encountered researching parts for high voltage DC: all the parts required such as bi-directional HV DC breakers seem to be very hard to come by = expensive.
So I gave up on HVDC ESS and instead buy short large diameter cables to connect 48v ESS to Inverters.

I'm guessing the reduction in amps when stepping up to high voltage helps with the DC arcing issues.

 

[OffGridForGood]

why would the current matter?
I have seen in testing that arc-faults typically are low current anyway - it is the voltages that seem to make extinguishing the arc problematic.

 

[Solar Guppy]

Can you run that Solis in offgrid mode and only use grid for charging and passthrough if needed.

Yes, with the understanding all hybrid Inverters even if configured for zero export which the Solis can do, there are times of load changes there can be short export to grid events.

There is the option to use an external isolated ( meaning a transformer based ) power supply and feed power to one of the 4 mppt channels, that would be 100% no back feed and would reasonable cost to implement.

The S6 has an integrated bypass which where the output can be grid, nothing or inverter output.

 

[Solar Guppy]

I would say, no not "Idential" - the energy, 10,000's of amps from the ESS, is not the same as the PV if there is a short.

All Solis listed approved batteries have breakers built-in and the inverter is fused internally. Sure if you have unprotected batteries all sorts of bad things can happen, doesn't make any difference if its 48 or 400V.

and the ESS is likely interior located, while the PV is always exterior, except for a pair of cables to the inverter/SCC.

That why all battery lines are required to be in conduit regardless of where they are located

I have considered this as well, but the fact remains, 48v DC has far lower potential to arc a small gap than 400v DC, and although 48v is nothing to be careless with, 400v is definitely a lot of potential in the seriously leathal range. Extinguishing a DC arc is already an issue at 48v, I can only imagine what is required to extinguish a 400v DC arc.

Gap where exactly? Using this calculator using exposed component leads comparing 60V to 500V it gives required safe distance to prevent arcing of 0.0042 ( 60V ) inches to 0.065 ( 500V ) inch or 3/125" to 13/200"

Again, its all fused, breaker and in conduit, If your not doing this for 48V you have similar dangers regardless of the voltage. I understand the concerns, but this all smacks of FUD

So I gave up on HVDC ESS and instead buy short large diameter cables to connect 48v ESS to Inverters.

Understood and being comfortable with what you build is very important!

 

[peufeu]

I built my installation 2 years ago and at that time the only approved offerings with HV batteries were not really attractive (read: cost a lot more than they're worth) so I guess I'm married to my 48V pylontechs now. But there's a lot of action on the HV side, cool things are happening! I guess the bureaucrats will catch up in a few years, make it illegal, then some years later make it mandatory, as usual...

 

[Rational]

Still doing my due diligence daily.

 

[Daddy Tanuki]

it looks to me like they are trying to force users to buy strictly from them, or they subsidiaries. I would have some questons about that sales model.

 

[Rational]

Yep. And I'm in talks with Seplos about getting their S4 stack(s), and was just told this:

So there's that too. But impressive she checked proactively with Solis directly without my prompting. So that's quality right there. She's searching for other brands now. Not so sure there are any that are split phase though that support HV batteries other than Solis and FoxESS. Deye's upcoming model won't be out for awhile.

Megarevo has one but I've read on here to stay away as their firmware is terrible and support is non responsive.

So even if Solis had warranty here in Japan, they would VOID it according to their docs if I use it with a battery not on the list anyway.

So the sales vendor would have to back up the warranty themselves.

 

[peufeu]

Yes

Regulatory eggheads are squirmish about HV batteries so they put a lot of red tape in the way, small little details like mandating 300€ type B RCDs. I don't know about Japan but here you won't pass inspection if the manufacturers of inverter and batteries do not give you the anointed paperworks. Besides the warranty stuff, Solis is probably covering their ass legally behind the scenes.

As I said before, for batteries you have three styles. Since these are long lived products I consider reliability including the company, ie what happens if it fails after the company goes down.

- One-big-box: not upgradable, if any component fails you have to RMA the whole thing and it weight a ton

- One BMS on top of a tower of batteries: upgradable by adding batteries but the BMS is a single point of failure, if it fails after the company went down your battery tower becomes decoration

- Independent modules: seems the best option, if one fails after the company went down you can still use the others

Now I'm off to order some XP-C-15-712-3 stickers, because of course you have to put big warning stickers everywhere

 

[Daddy Tanuki]

Yes

Regulatory eggheads are squirmish about HV batteries so they put a lot of red tape in the way, small little details like mandating 300€ type B RCDs. I don't know about Japan but here you won't pass inspection if the manufacturers of inverter and batteries do not give you the anointed paperworks. Besides the warranty stuff, Solis is probably covering their ass legally behind the scenes.

japan is the same IRT regulations and red tape, but too the nth level

As I said before, for batteries you have three styles. Since these are long lived products I consider reliability including the company, ie what happens if it fails after the company goes down.

- One-big-box: not upgradable, if any component fails you have to RMA the whole thing and it weight a ton

- One BMS on top of a tower of batteries: upgradable by adding batteries but the BMS is a single point of failure, if it fails after the company went down your battery tower becomes decoration

- Independent modules: seems the best option, if one fails after the company went down you can still use the others

this is why I support independent modules, inverter is inverter, SCC's are SCC's and BMS's are BMS's etc. etc. you can replace, or mix and match as you see fit.

If I was doing a HV system I think I would still probably build my own battery. even if I had to cobble up my own homebrew BMS for it. batterium can support up to 250 cells. 100-110 cells would put you in the HV territory you could even parallel 2p100s with even small cells and get a crazy large battery. 100 of the 280-300 ah cells would give you over 105 kWh of storage which will go a long ways on a japanese sized house. the hard part would be the solar charge controller you would need ot find one that charges at the voltage you want to run. I am sure that @Rational has looked into this somewhat as well

the batrium itself can talk via can bus. Myself being a Menonite (or something eerily similar when it comes to tech) I would not profess to understand skynet so YMMV.

 

[Rational]

Thanks for that Daddy.

But at my current experience level with making my own battery packs, which is zero, I'm thinking that is where the risk for me getting electrocuted would be highest especially with HV battery builds. Even Solar Guppy mentioned HV battery builds are challenging even for him.

If it were 48v I'd build my own batteries. Well, maybe. It seems that the cost benefit of DIY of late isn't quite there anymore and it's about the same price or even less to have them prebuilt at the factory.

For me with trying to install a complete system, I like the idea of focusing my time and energy on the other areas of the build right now if I'm going to do it myself. Having the battery already sealed and tested is a huge time saver and reduces my risk to just connecting the two main leads to the inverter.

I guess I have to decide if the Solis is even an option. Right now Solis isn't answering my questions citing I'm in Japan. So that's not giving me a warm fuzzy. Their docs also state the warranty will be void if used with a battery not on their compatability list. Which includes both Seplos and Sunpal curently. And I won't spend the high price tag on the ones that are.

So if I do this, it will be unsupported.

Seplos told me today that Solis will make the certificate for Japan. Not sure how quaranteed that is or how long that might take. But encouraging.

I almost sent the money for the S6 today but we have a typhoon heading our way as of today, so I'm taking tomorrow off to prepare. I put a hold on the order until after the typhoon passes to have a final think on if I want to pursue this thing with Solis and HV. It is the best value for the money option on the market right now though and therefore the most future proof play for the money currently.

But the AIO units I'm hearing have to be shipped back to China should they fail. That's a costly PITA.

I know I can get Victron gear on amazon japan shipped right to my door should an inverter fail. I'd just need to run two of them to get split phase. But I know they support them in Japan as their support confirmed it when I inquiired. If I go this way, that opens up the 48V battery build options again for me. So I'll give myself one last think on it the rest of this week. We'll see...

 

[Hedges]

Still doing my due diligence daily. View attachment 242881

I see a picture of LG RESU-10H, although table says LG RESU Prime 10H. These are all LV (about 150V) batteries with DC/DC converter to 400V (I see 480V max.)

I think this series of LG batteries is to be avoided. It costs more than LiFePO4 batteries, has half the cycle life (3000 vs. 6000 cycles), is of an "explody" chemistry.

I've been running LG RESU-10H with SMA Sunny Boy Storage since Spring 2024. It has 9.8kWh gross, 9.2kWh usable capacity.
SBS reports indicate I get back about 80% of what I put in, and about 9.x kWh per cycle drawn out.
Two weeks ago I mounted it outside (was bench testing on dolly in garage). Power drawn has declined rapidly to only 7.5kWh from 100% to 0%. Charging puts in about 9kWh.

Consider BYD. I think they are a top brand with quality batteries. Don't know about the others.
Another forum member has been running BYD with SBS.


Something which has been mentioned on the forum is a protocol translator to let several HV inverters communicate with several repurposed EV batteries complete with EV BMS. That may give you relatively safe access to HV.

R

Post in thread 'Inverters that support high voltage (500v) storage batteries'

Jun 19, 2024

Thanks guys. Appreciate the replies.

Welcome. I have Solis in the UK, with 48V batteries.

I _thought_ (though I could be wrong) that the HV Solis inverters use some proprietary comms with the battery BMS which means that building a DIY battery system for them is either difficult or impossible. IIRC @Solar Guppy has experience with the HV Solis range, so might be worth searching on his threads.

@SeaGal Thanks for that.

How do you like your Solis? How's the app quality and reliability? Good company? Good support? No issues overall?

Dala's 'battery-emulator' is able...

• Rational

• 

Bear in mind that when you connect HV battery to inverter then disconnect it, inverter for a time serves as a source for dangerous HV (don't ask me how I know.)

I would like to build DIY HV battery from cells, need to select suitable BMS to talk directly or through translator with inverter. I think I would use 8 poles of breaker to segment 400V worth of battery into eight 48V batteries before wrenching on them.

 

[peufeu]

I think this series of LG batteries is to be avoided.

There's a guy on a forum, his stopped working. No part of the thing can be debugged. No modules. Can't open it, because there's high voltage inside! The manufacturer can't help you fix it, because they don't want to get sued if you zap yourself doing so. Also it's NMC.

He had to ship the whole battery to the manufacturer.

Might want to check how much that costs given the size, weight, and explodey nature of this thing, better hope it's installed on the ground floor and you got adequate equipment to roll it out, lift it on a pallet, package it, gotta insure it during shipping, if it blows because someone whacks it with a forklift who's responsible, etc. This earns a solid "meh" on the maintenance front...

 

[Daddy Tanuki]

I see a picture of LG RESU-10H, although table says LG RESU Prime 10H. These are all LV (about 150V) batteries with DC/DC converter to 400V (I see 480V max.)

I think this series of LG batteries is to be avoided. It costs more than LiFePO4 batteries, has half the cycle life (3000 vs. 6000 cycles), is of an "explody" chemistry.

One of those NASA level Technical terms... kind of like an unplanned disassembly event?

I would like to build DIY HV battery from cells, need to select suitable BMS to talk directly or through translator with inverter. I think I would use 8 poles of breaker to segment 400V worth of battery into eight 48V batteries before wrenching on them.

yeah but each succeeding breaker would be a higher voltage would it not? If i misread, my apologies, so 48 +48 +48 +48 +48 that would at the breaker be 48, then 96, then 144, then 192, then 240 etc. etc. correct? basically each breaker would have a higher voltage requirement. i guess you could do knife switches and open the first one under zero draw, and then unhook the rest.

 

[Rational]

I've been forgetting about the SRNE HESP48120U200-H 12k inverter option. Not HV, but certified and a popular brand here in Japan I hear. So will look at this closely this week. Got one of the five solar companies currently bidding on our house coming back tomorrow. I am going to hit him up with this inverter instead of the Delta and Intelus model he's trying to pawn off on us.

Will also ask if he is willing to install the Solis S6 11.4k and/or perhaps the Victron Multiplus-II 5k if he can get any of these certified for grid use. But with Victron it would require two inverters for split phase. So doubling the price.

Also going to ask him for 36x445w panels for a total of 16000w of total pv power. Which is too much for the Victron being only 5k, right?

The SRNE might just end up being the best value for Japan here currently if the HV stuff is not able to pass grid certification yet.

https://www.srnesolar.jp/userfiles/files/2024/02/28/SRNE_HESP%20series_US_48V_8~12kW_120V&240V_Solar%20storage%20inverter_datasheet_V1.0.pdf

 

[Hedges]

One of those NASA level Technical terms... kind of like an unplanned disassembly event?

RUD, "Rapid Unscheduled Disassembly"

yeah but each succeeding breaker would be a higher voltage would it not? If i misread, my apologies, so 48 +48 +48 +48 +48 that would at the breaker be 48, then 96, then 144, then 192, then 240 etc. etc. correct? basically each breaker would have a higher voltage requirement. i guess you could do knife switches and open the first one under zero draw, and then unhook the rest.

Nope, all > 60VDC.

In writing this I forgot that I previously realized they need to be ganged. And can be ganged with AC breaker, eliminating charging source. And can be ganged to a remote trip.

Any one series switch opened would see full 480VDC (or whatever that pack makes; my LG RESU-10H is 480VDC).
If all open at once, voltage is split among them. Same as 2-pole Square-D QO UL listed for 60V/pole but Square D Certified for 125V with 2 poles working in series (don't have to be adjacent in the circuit, can be one +, one -)

Now, if one end of battery is grounded and an intermediate node shorts, then yes voltage depends on where in the stack short occurs.

I'm also not 100% sure about 2x 300VDC poles for 600V PV string which is floating but could have faults at either end. Could we get 600V across a single 300V pole?

 

[peufeu]

16000w of total pv power. Which is too much for the Victron being only 5k, right?

Mutliplus does not have a limit on PV power, because it not have MPPT PV inputs. It is only a charger/inverter. If you want panels you have to add MPPT chargers.

It is well suited for offgrid use. In this use case:
1- AC output power should be as low as possible, because inverter idle losses are proportional to it
2- Battery charging power should be as high as possible, to rush charge the batteries if you get 1 sunny day and a week of rain
3- Peak power should be enough to start motors

AIO hybrids are not well suited for offgrid because you get one big box and the PV charging power is about the same as the inverter's AC output power, so conditions 1 and 2 above are not fulfilled. Also idle losses tend to be high. AIO's usually have low peak power because the grid provides it instead of the inverter, so condition 3 is not fulfilled.

Victron is more flexible as you can always add more panels by adding more MPPT chargers. But you have to buy a lot of stuff.

For grid tied use the drawback is converting all the PV power down to 48V then up to mains voltage, which increases losses.

It is also very expensive. An offgrid system is designed to provide a service, a grid tied system is intended to make money. Very different goals.

 

[Hedges]

There's a guy on a forum, his stopped working. No part of the thing can be debugged. No modules. Can't open it, because there's high voltage inside! The manufacturer can't help you fix it, because they don't want to get sued if you zap yourself doing so. Also it's NMC.

He had to ship the whole battery to the manufacturer.

Might want to check how much that costs given the size, weight, and explodey nature of this thing, better hope it's installed on the ground floor and you got adequate equipment to roll it out, lift it on a pallet, package it, gotta insure it during shipping, if it blows because someone whacks it with a forklift who's responsible, etc. This earns a solid "meh" on the maintenance front...

Mine is now safely hanging on a block retaining wall away from the house.
Ethernet cable to my lab so my laptop is in the shade where I can read it.

Thread 'Sunny Boy Storage and LG RESU-10H, a work in progress'

Aug 24, 2024

Sunny Boy Storage is SMA's Power Wall, and AC coupled battery for peak shaving and backup. It connects to a third-party external battery.

Sunny Boy Storage 3.8-US / 5.0-US / 6.0-US | SMA America

Discover the flexible Home Energy Solution: The SMA Sunny Boy Storage 3.8-US / 5.0-US / 6.0-US battery inverter! ► Find out more about its benefits!

www.sma-america.com

LG RESU-10H is a 150V lithium battery with DC/DC converter to present 400V to the outside world. Unlike BYD and others that are natively 400V.
Available as type "C" compatible with SMA or type "R" compatible with Solar Edge and some other brands.

RESU10H | LG Home Battery

The RESU10H is part of the high voltage RESU range. Using state-of-the-art lithium-ion battery technology, the RESU10H will be there to store energy from your solar panels or the grid during the day. The battery powers your home during the evening, during power outages, when the sun is not...

www.lghomebattery.com.au

I acquired 3x SBS and 2x LG RESU-10H. Unfortunately, that was...

• Hedges
• Replies: 3
• Forum: Residential Solar

• 

I was thinking about recalls, warranty, etc. but think LG only plays with installers who got their training. Maybe I'll get that.

 

[Rational]

Mutliplus does not have a limit on PV power, because it not have MPPT PV inputs. It is only a charger/inverter. If you want panels you have to add MPPT chargers.

It is well suited for offgrid use. In this use case:
1- AC output power should be as low as possible, because inverter idle losses are proportional to it
2- Battery charging power should be as high as possible, to rush charge the batteries if you get 1 sunny day and a week of rain
3- Peak power should be enough to start motors

AIO hybrids are not well suited for offgrid because you get one big box and the PV charging power is about the same as the inverter's AC output power, so conditions 1 and 2 above are not fulfilled. Also idle losses tend to be high. AIO's usually have low peak power because the grid provides it instead of the inverter, so condition 3 is not fulfilled.

Victron is more flexible as you can always add more panels by adding more MPPT chargers. But you have to buy a lot of stuff.

For grid tied use the drawback is converting all the PV power down to 48V then up to mains voltage, which increases losses.

It is also very expensive. An offgrid system is designed to provide a service, a grid tied system is intended to make money. Very different goals.

Oh, that's right. I was forgetting the multiplus had external MPPT. What about the Quattro 10k 48v 120v models instead? Any better off? Only major downside is that they're $2700 each and I'd need two. Oh, are these not able to be grid tied? If not, it seems Victron doesn't have anything above 5k? So I'd need even more of them? Seems costly.