Decision on Inverter

2009Bounder2020

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104
Might consider making the air conditioning more efficient. We went to geothermal and its much easier to run with solar.
Granted i still use natural gas for the 300 gallons of water heaters, with 4 teenagers i can even get in a hot shower now.l
 

the_colorist

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Super deals on the SI6048's. Jump on those if you want to go that route.

That said, an alternative option would be Victron units. The Multiplus II 5K specifically. They do require adding a split-phase transformer externally but if you get them from an installer/dealer such as myself or someone else, you could be looking at a cutting-edge system akin to SMA for decent price. Just 2 would be a surge capacity of 18KW. 3 would be 27KW. Would easily start your HVAC.


If you went Victron you can also DC+AC couple. Having the advantages of both worlds while still have the entire system on a single controller.

You could also consider DEYE. Thier units are essentially identical to SOL-ARK. It's been debated but IMHO they are the OEM for SOL-ARK. Simply too many factors point to that. You can get the 7.6KW model for under $2K, making 2 of them less than $4K before shipping. 3 of them however would give you a max PV input of ~29KW.

The trick though is buying them from China directly. Some hoops to jump through there as DEYE is not officially allowed contract-wise to sell to the USA directly. More on that in other parts of the forum.

 

TKB4

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To Fahmula
That is the Growatt I was trying to find but I thought it was an HVM model so it has the 250 volt pv input. The problem is the pv array input is 7,000 watts. I thought surely it is 7,000 watts for each MPPT controller but I have been unable to confirm this . When I tried to confirm it on the 1200t dvm and 1200t HVM models I was told that 7,000 watts is the total maximum input . Of course if this is 3500 watts per MPPT it further limits pv input if you cannot match exactly 3500 watts . In my case I would only be able to attach 3300watts to each for a max of 6600 watts and I have almost twice that much in my array and need another 7,000 or so. The other concern is I believe the standby draw is 180 watts and can't confirm any economy standby mode. The PV input alone is a no go for me even at 250 watts unless possibly it could be programmed to only draw from the batteries and I could charge them with another controller and let it use its max pv input directly. The sunny islands are a very good option also
 

TKB4

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Hedges
yes the solar cabinet was a great value but no longer available.
 

TKB4

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Bounder20
I have a geothermal unit downstairs which is what I am trying to decrease the starting amps on. Its a 5 ton 2 stage climate master Tranquility 30 that I limit to using stage 1 for improved efficiency as well as I dont need stage 2 unless its close to zero which is about 2 days every 3 or 4 years here. Upstairs is a 3 ton 21 SEER inverter unit and isn't used but a couple of summer months for now when kids home. My house is Dryvit but 6500 sq ft so also well insulated but large. Both units will be on those months but not actually operating at the same time most of the time but when they are and lights and appliances on at same time I would have a constant use of around 12,000 watts and thats without oven or dryer which I can easily manage'

I thought about preventing both HVAC s from being on at the same time which I could have done automatically at the breaker level but this screws up the thermostat settings also so more complicated.
 

TKB4

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Messages
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Might consider making the air conditioning more efficient. We went to geothermal and its much easier to run with solar.
Granted i still use natural gas for the 300 gallons of water heaters, with 4 teenagers i can even get in a hot shower now.l
I have a gas Tankless Rinnai 98 unit for 3 years now that I bought from surplus on eBay for $900 new in damaged box and produces copious amounts of hot water enough for 3 or 4 high flow shower heads at the same time! Looks at this much cheaper and tons less space than 3 water heaters but you need gas line delivery of 199,000 BTU s or get a little smaller unit. You can then use your water heaters as preheaters with pv direct heating and rarely need the tankless.
 

TKB4

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Joined
Dec 2, 2019
Messages
208
Super deals on the SI6048's. Jump on those if you want to go that route.

That said, an alternative option would be Victron units. The Multiplus II 5K specifically. They do require adding a split-phase transformer externally but if you get them from an installer/dealer such as myself or someone else, you could be looking at a cutting-edge system akin to SMA for decent price. Just 2 would be a surge capacity of 18KW. 3 would be 27KW. Would easily start your HVAC.


If you went Victron you can also DC+AC couple. Having the advantages of both worlds while still have the entire system on a single controller.

You could also consider DEYE. Thier units are essentially identical to SOL-ARK. It's been debated but IMHO they are the OEM for SOL-ARK. Simply too many factors point to that. You can get the 7.6KW model for under $2K, making 2 of them less than $4K before shipping. 3 of them however would give you a max PV input of ~29KW.

The trick though is buying them from China directly. Some hoops to jump through there as DEYE is not officially allowed contract-wise to sell to the USA directly. More on that in other parts of the forum.

The victrons might work if they have grid input and bypass also but then I would need a transformer for input and output both wouldn't I?

I love the idea of 2 or three of the DETE units I could probably get by with just 2 units. If they are similar to the solark 8 or 12 that would be my choice especially if they blend grid power with solar to meet the load. I need to research these much further.

I wonder why hybrid inverters are not designed to be capable of bypassing either full grid power or at least say double their capacity instead of the same or slightly higher capacity this would be very desirable to me and probably many others.

I did consider using 2 large transformers one each for input and output along with stacking MPP european hybrid units that can blend grid power but the complexity and loss of efficiency turned me off.

My ideal inverter 240 split phase power
provide at least 12,000 continuous watts. at least 16,000watts pv input. at least 250 volt pv input, Surge to at least 24,000 watts for 10 seconds, bypass at least 16,000 watts from grid, draw around 100 watts or less in economy standby mode. Weigh less than 150 lbs and be relatively quiet using 8,000 watts one unit easy to set op remote monitoring and $5,000 or less including shipping. This is a lot to ask but kinda like Solark with their current 12 model which is actually 9,000 watts max and one about 12,000 to 15,000 max and they would cover almost all the whole house and off grid market with only 2 models which would then reduce inventory and could dramatically lower price through volume.

Companies are just plain stupid for not coming up with inverters similar to this at this price point. I would stack 2 Solark 12 s in a heartbeat if they were $4,000 each or less.



Thanks for your response
 

Fahmula

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Joined
Oct 7, 2020
Messages
123
To Fahmula
That is the Growatt I was trying to find but I thought it was an HVM model so it has the 250 volt pv input. The problem is the pv array input is 7,000 watts. I thought surely it is 7,000 watts for each MPPT controller but I have been unable to confirm this . When I tried to confirm it on the 1200t dvm and 1200t HVM models I was told that 7,000 watts is the total maximum input . Of course if this is 3500 watts per MPPT it further limits pv input if you cannot match exactly 3500 watts . In my case I would only be able to attach 3300watts to each for a max of 6600 watts and I have almost twice that much in my array and need another 7,000 or so. The other concern is I believe the standby draw is 180 watts and can't confirm any economy standby mode. The PV input alone is a no go for me even at 250 watts unless possibly it could be programmed to only draw from the batteries and I could charge them with another controller and let it use its max pv input directly. The sunny islands are a very good option also
The 7kw limit is the biggest issue for me too. I was considering adding another MPPT to work in parallel with the growatt. 180w is a lot especially with no sun.
 

TKB4

Solar Enthusiast
Joined
Dec 2, 2019
Messages
208
Super deals on the SI6048's. Jump on those if you want to go that route.

That said, an alternative option would be Victron units. The Multiplus II 5K specifically. They do require adding a split-phase transformer externally but if you get them from an installer/dealer such as myself or someone else, you could be looking at a cutting-edge system akin to SMA for decent price. Just 2 would be a surge capacity of 18KW. 3 would be 27KW. Would easily start your HVAC.


If you went Victron you can also DC+AC couple. Having the advantages of both worlds while still have the entire system on a single controller.

You could also consider DEYE. Thier units are essentially identical to SOL-ARK. It's been debated but IMHO they are the OEM for SOL-ARK. Simply too many factors point to that. You can get the 7.6KW model for under $2K, making 2 of them less than $4K before shipping. 3 of them however would give you a max PV input of ~29KW.

The trick though is buying them from China directly. Some hoops to jump through there as DEYE is not officially allowed contract-wise to sell to the USA directly. More on that in other parts of the forum.

at the link provided the specs are all pretty favorable except one they appear to be european single phase 230v output otherwise 2 of them would suit me pretty well but I also need 240 split phase grid input. If I was totally off grid this would be ok if I got a european model generator or conversion etc.
 

the_colorist

"Move over... let me fix it" Installer/Engineer
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Location
USA - Working in Central America
The victrons might work if they have grid input and bypass also but then I would need a transformer for input and output both wouldn't I?
No need for 2x transformers. When AC-in closes and connects L1-L2 to AC-Out, it's passing through power and the transformer on the AC-Out will still provide a neutral.

Here is a schematic you can look over.

You can pass through the inverter OR you can passthrough using an external transfer switch (cheap). The Multiplus II can pass through 50A (12KW) per unit. More than double its capacity.

Are you needing to sell back to grid or just grid backup. Forgive me if you already mentioned it, I haven't had time to read the entire thread.

The Deye inverters are natively Split-Phase. That's why they have LP1-US on the end of the model. You have a choice of either LP1-US or LP1-EU. They are UL1741/Rule21 certified.

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TKB4

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No need for 2x transformers. When AC-in closes and connects L1-L2 to AC-Out, it's passing through power and the transformer on the AC-Out will still provide a neutral.

Here is a schematic you can look over.

You can pass through the inverter OR you can passthrough using an external transfer switch (cheap). The Multiplus II can pass through 50A (12KW) per unit. More than double its capacity.

Are you needing to sell back to grid or just grid backup. Forgive me if you already mentioned it, I haven't had time to read the entire thread.

The Deye inverters are natively Split-Phase. That's why they have LP1-US on the end of the model. You have a choice of either LP1-US or LP1-EU. They are UL1741/Rule21 certified.

View attachment 32599
ok thanks a lot I was looking at the wrong models but I didn't see other models on their product lineup. I am NOT selling to grid just using it for for whatever power I generate and charge batteries with. I would rather not use an external switch backup since it would be manual and the inverter couldn't automatically switch back on when load decreased. I had actually thought of an external switch to place one of the HVAC units on straight grid power at times which wouldn't be hard to do or just turn it off at breaker if not needed for extended time. Would it harm most inverters to let them go to overload and bypass until load lowers fairly often like every time a HVAC unit comes on I would assume it If the viltron has the ability to operate a relay switch for unlimited passthrough that would be great as long as it could reconnect automatically when load decreases. I would think a relay switch etc that does this maybe using the dry contact generator control would be in demand by many users. Thanks again you are very helpful.
 

TKB4

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ok thanks a lot I was looking at the wrong models but I didn't see other models on their product lineup. I am NOT selling to grid just using it for for whatever power I generate and charge batteries with. I would rather not use an external switch backup since it would be manual and the inverter couldn't automatically switch back on when load decreased. I had actually thought of an external switch to place one of the HVAC units on straight grid power at times which wouldn't be hard to do or just turn it off at breaker if not needed for extended time. Would it harm most inverters to let them go to overload and bypass until load lowers fairly often like every time a HVAC unit comes on I would assume it If the viltron has the ability to operate a relay switch for unlimited passthrough that would be great as long as it could reconnect automatically when load decreases. I would think a relay switch etc that does this maybe using the dry contact generator control would be in demand by many users. Thanks again you are very helpful.
I will look at the other threads about Deye but doesn't make much sense to make 240 split phase units if they dont export to us when canada and a few others are only places that utilize the split phase. Maybe the company is banned to import to US or has an agreement with Solark etc.
 

TKB4

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The 7kw limit is the biggest issue for me too. I was considering adding another MPPT to work in parallel with the growatt. 180w is a lot especially with no sun.
I have other MPPT controllers I would like to use with most any invert I might get to add more charing capability from for example east and west facing arrays and they have 450 volt pv input BUT I am told since the hybrid inverters check the battery voltage they would be fooled into turning off their chargers or possibly cause damage. I have even considered a separate battery bank using this chargers and a switch to change battery banks since you can't connect the 2nd battery bank to the first without matching the voltages. the switch would disconnect the first battery bank the n rconnect the second battery bank to the inverter.
 

TKB4

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I will look at the other threads about Deye but doesn't make much sense to make 240 split phase units if they dont export to us when canada and a few others are only places that utilize the split phase. Maybe the company is banned to import to US or has an agreement with Solark etc.
It sounds like the DEYE units might be desirable for both of us .
 

Hedges

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I wonder why hybrid inverters are not designed to be capable of bypassing either full grid power or at least say double their capacity instead of the same or slightly higher capacity this would be very desirable to me and probably many others.

For their original European market SMA Sunny Island did pass through 2x the inverter capacity.
At 230V and 56A relay, the 6 kW inverter could pass through over 12 kW. They could also manage 12 kW of Sunny Boy GT inverter.
With the 120V US model, they can only pass through 6.7 kW so if grid-tie that is the most Sunny Boy they can support. If off grid (or set for no export), they can take in that much from generator (or grid) and still have 12 kW of AC coupled Sunny Boy.

I considered external transfer switches. But when prices came down, I installed 4x SI6048 wires 2s2p. That gives me 112A 120/240V pass-through, 23 kW continuous from battery, support for up to 27 kW of Sunny Boy. If configured for off-grid it would support 48 kW of Sunny Boy.

What you can do is set up an automatic or manual transfer switch. Put critical loads directly on your hybrid inverter's output, and use the transfer switch for non-critical loads. You'll want to turn off anything it can't power such as electric furnace. I have a "load shed" relay so the non-critical loads are disconnected at 70% DoD but critical ones keep running.
 

TKB4

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For their original European market SMA Sunny Island did pass through 2x the inverter capacity.
At 230V and 56A relay, the 6 kW inverter could pass through over 12 kW. They could also manage 12 kW of Sunny Boy GT inverter.
With the 120V US model, they can only pass through 6.7 kW so if grid-tie that is the most Sunny Boy they can support. If off grid (or set for no export), they can take in that much from generator (or grid) and still have 12 kW of AC coupled Sunny Boy.

I considered external transfer switches. But when prices came down, I installed 4x SI6048 wires 2s2p. That gives me 112A 120/240V pass-through, 23 kW continuous from battery, support for up to 27 kW of Sunny Boy. If configured for off-grid it would support 48 kW of Sunny Boy.

What you can do is set up an automatic or manual transfer switch. Put critical loads directly on your hybrid inverter's output, and use the transfer switch for non-critical loads. You'll want to turn off anything it can't power such as electric furnace. I have a "load shed" relay so the non-critical loads are disconnected at 70% DoD but critical ones keep running.
again great info and ideas. I would use in no sell mode all the time and grid connected and it sounds like I shouldn't need a critical loads panel with either grid up or generator running al all since my loads will never exceed 16,000 watts and thats only briefly and the sunny boys can do over 7,000 watts for 30 minutes and I think 11,000 watts for a second or so. In addition they can bypass extra grid power if I am understanding you correctly.
 
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HaldorEE

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Hedges
yes the solar cabinet was a great value but no longer available.
Want to bet he bought it? I would have clicked "Buy it now" before posting that link. What a smoking deal.

You could sell one and keep the other for an incredibly cheap, high quality 6KW solar system. Does anyone doubt you could get > $2000 for one of those cabinets?
 

Hedges

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I was tempted when I saw the cabinets posted some weeks ago. But I already have more inverters than I know what to do with.
I was tempted again this week when I saw another auction of DC Solar trailers. Cabinet with two Sunny Island, two forklift batteries, Midnight SCC, diesel generator with a couple hours on it PV panels on tilt mounts. I want it! but, I don't actually need a generator, trailer weight exceeds my hitch rating, would take up extra space in my driveway or yard, not much sun exposure where it would go.

You want two Sunny Island, not just one. This gives you 120/240V split-phase for not much more than adding a transformer and supports up to 13 kW of Sunny Boy backfeeding the grid.

Hard to sell any of this stuff because the market is glutted. DC Solar got $1 Billion to spend and there are thousands upon thousands of these trailers plus new equipment not yet installed.
 

Hedges

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again great info and ideas. I would use in no sell mode all the time and grid connected and it sounds like I shouldn't need a critical loads panel with either grid up or generator running al all since my loads will never exceed 16,000 watts and thats only briefly and the sunny boys can do over 7,000 watts for 40 minutes and I think 11,000 watts for a minute or so. In addition they can bypass extra grid power if I am understanding you correctly.

Critical loads panel and load-shed relay is for when on battery and SoC gets low.
I only have Sunny Boys on critical loads panel - the entire house would be load-shed at 70% DoD, but Sunny Island remains up down to 80% DoD so when the sun comes up Sunny Boys see AC and start delivering power.
Eventually I'll shed less important loads like laundry and outdoor lights at 20% DoD. I plan to wire things as (on-grid) OR (> 80% SoC).
You may want separate critical loads rather than running the generator at night. If your PV is AC coupled (Sunny Boy) rather than DC coupled then you should separate them.

I have net metering so Sunny Boys backfeed the grid.
DC coupled PV doesn't backfeed the grid with Sunny Island unless SCC are set to a higher voltage than SI.

I'm not sure how well Sunny Island supports zero-export. So long as PV is less than battery charging plus consumption, you would be a net consumer. I think SI would also suck down power from the grid to recharge batteries faster. Once battery charge current tapers off and you have surplus PV, to prevent export it can disconnect from grid; it would then raise frequency to curtail production.

What you might like is to remain grid connected with batteries floating and PV curtailed to match load. SI can't do that because it uses frequency shift. Possibly Sunny Boy Storage (400V lithium battery) could, because it has a data link to newer model Sunny Boy. But it is featured as working with all GT inverters; for most of those it would have to cycle batteries while leaving the GT inverter on at full output or knocked off line for zero output. Note that Sunny Boy Storage is a wimp, can't power as much or offer the surge capability of Sunny Island.

But compared to Sunny Island plus generator, obviously Sunny Island plus grid is going to be cheaper and less maintenance.
 

TKB4

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Want to bet he bought it? I would have clicked "Buy it now" before posting that link. What a smoking deal.

You could sell one and keep the other for an incredibly cheap, high quality 6KW solar system. Does anyone doubt you could get > $2000 for one of those cabinets?
Might not be as easy to sell as 6kw 120 volt system. I am trying to decide on the last pair before they are gone. Obviously a great deal but still think I could do what I need with 2 MPP LV6548 s and now researching the DEYE. I do like the grid blending and higher surge capability
 
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