What is the best way to add inverters.

[Guda]

I know the best way to build a system is do the math & get all the stuff. But how about when you have to build as you go while trying to live off it. And having dreams of more.

"Bare bones" for this system is

20x 265w pv
Midnite C 250
2 tesla battery modals 48v
And the inverter?

I want 120/240v & 12kw ultimately. Maybe more. I have a 200a breaker box I plan on using. I see people are running inverters in parallel. If I got a 120v 6000w inverter to start. Would it have to run its own breaker box or could it be added to something like another 120v 6000w inverter into the same breaker box to make 240v? I'd like to buy 1 inverter now & one bigger one later.

I guess the questions is about adding inverters & paralleling them.

Much thanks!

 

[Ampster]

Do you have access to a grid connection? I understand this is the Off Grid section and you had batteries on your list.

 

[Guda]

Nope. Only power I have is a cic powerbox in my truck.

 

[Guda]

Just found this. I think it pretty much answers my questions

3000W Off Grid Stackable PV Inverter 80A MPPT Solar Charger DC 48V to 110V 120V with 40A Utility Charger 50HZ 60HZ

3000W Off Grid High Frequency Stackable Inverter 80A MPPT Solar Charger DC 48V to 110V 120V with 40A Utility Charger 50HZ 60HZ. M3000H-48LV

www.sigineer.com

 

[Ampster]

I am not familiar with the options available with purely off grid inverters. Yes, you can buy a cheap 120v inverter and later parallel it with another to get a true 240v split phase. Perhaps others with more experience can weigh in on whether that is the best long term strategy versus going with a more expensive 240v split phase inverter in the first place. There are a lot of options out there.

 

[John Frum]

I am not familiar with the options available with purely off grid inverters. Yes, you can buy a cheap 120v inverter and later parallel it with another to get a true 240v split phase. Perhaps others with more experience can weigh in on whether that is the best long term strategy versus going with a more expensive 240v split phase inverter in the first place. There are a lot of options out there.

The inverters need to support synchronisation to be used together.

 

[Ampster]

The inverters need to support synchronisation to be used together.

Thanks for the clarification. I use the term parallel and Outback uses the term stacked. There may be nuances that need to be investigated. For example Outback Skyboxes can be stacked and they can do AC coupling but when stacked, they cannot do AC coupling.

 

[John Frum]

Thanks for the clarification. I use the term parallel and Outback uses the term stacked. There may be nuances that need to be investigated. For example Outback Skyboxes can be stacked and they can do AC coupling but when stacked, they cannot do AC coupling.

If the units are exactly synchronised "on the beat" you get twice the amperage at the same voltage.
If the units are synchronised "half a beat" apart you get twice the voltage at the same amperage.

 

[Ampster]

So if I equate beat to phase then that term applies to synchronizing two 120 volt single phase inverters. In that case one would have a choice about increasing the Amperage at 120 volts or increasing the voltage at the same amperage.

Stacking or paralleling two 240 volt split phase inverters would increase the Amperage but remain 240 volts

This is what makes answering the question about "the best way to add inverter?" a difficult thing without a long term goal or strategy.

 

[Guda]

That unit I linked 2 can be "stacked" up to 6 units. Each unit is 120v but when you "stack" them you can get 3 phase or 240v. Sounds perfect. Only thing is I am not 100% sure that inverter is okay for model x 48v battery. Can someone confirm that for me? Please thank you. I actually cant believe how perfect these seam to be me. I'm just waiting for the "those wont work" or " that co is bad"

Those units are also SCC & chargers. Seams like a lot going on for such a good price. If they are good. Once I have 4 of them I could change over all my solar to them & use my MC250 for a wind turbine.

 

[windtrader]

So "stacking" is the operative word to ensure combining inverters later do not cause heartburn.

 

[Ampster]

So "stacking" is the operative word to ensure combining inverters later do not cause heartburn.

I think there are three terms being referred to above and I do not think any of them ensure there will not be hearburn. The only insurance is understanding the issues ahead of time and wading through user manuals, watching videos and seeing real world examples. Someone also mentioned 3 phase but that is not typically found in homes. It is very efficient for large motors and that is why it is more common in industrial and commercial environments in the US. It is more common in Europe and other parts of the world. . One of my EVs use three phase motors driven by multifrequeny inverters. Fortunately the energy is stored in DC so I can charge them with split phase.