Hybrid Inverter sizing advice

beckkl

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If you're going split phase then yes, go for the 220v units. I haven't found a 120v unit over about 22 SEER rating. 3Kw on each leg gives you a lot of power to play with and makes it easier to load balance your draw since you'll be able to drop that right to a bog standard service panel.
I wish there were a better selection at the higher seer ratings. Only finding a handful of options.
 

SolarPrep

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beckki: the best units I've worked with are Mitsubishi, Fujitsu and Daiken. ( in the USA) The first two are my favorites. Fujitsu is a better value, but Mitsubishi has some really small head units, like 6000 BTU that are great. And don't forget that there are floor mounted consoles that are great to work with. You don't have to use a wall mounted unit if it is going to be in an area that the aesthetics would be offensive. Mini splits are highly efficient, ramp up slowly, and don't lose energy to duct work. Most of them run well on 208v if you end up going that route for some reason, but 220/240 is more common

Can you start by just putting in one unit? A word of caution: most HVAC people tend to oversize units, because they are more familiar with that practice with central A/C systems. With mini-splits, that is a mistake. (well, always a mistake, because an oversized unit doesn't perform as well)

Technicians detest the ceiling cassette models. They are much harder to install, the space is very cramped, and maintenance is difficult. And incredibly messy.

This may not help, but there is a place that sells surplus HVAC in Lebanon IN. If you go that route, be careful to make sure the components match. The heads have to match the compressor. I've seen some really good deals over there on new equipment. Some of them might be scratch and dent, but they are good about calling it out, and provide pictures.

Your newer choice for the inverter is likely to be a better fit for you overall. I have not worked with that brand, so don't have comments on it that are specific. It looks like a good unit though.
 

JustPractical

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Nope, right there in the description it says:

HYBRID LV6048 6kW Split Phase 120V/240V- 2 x 80MPPT Inputs (8Kw Solar)​


If you grab the updated manual it shows on page 9 it shows 2 PV inputs.

It's the same money either way, the biggest advantage to doing a 6Kw over 2x 3Kw's is that with the 6Kw there's only 1 AC-In, 1 AC-Out and 1 DC-In, so you save on wiring as opposed to 2, 2, and 2.
Newbe question - if he went with the 2x3kw instead of the single 6kw, would he have the advantage that he could run part of his pv array to once controller and part to the other (to mitigate effects from shading)?
 

Rednecktek

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As I understand it the 6Kw units are just 2 of the 3Kw units mounted into a single box, so same diff.
 

beckkl

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As I understand it the 6Kw units are just 2 of the 3Kw units mounted into a single box, so same diff.
I don't think that is the case. My understanding is that many of the 6Ks are low frequency inverters and can handle inductive loads better.
 

Rednecktek

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Oh! The reviews I saw on the MPP and the Growatt were both just two setups in the same box with cables connecting the sets. At least that's what it looked like when the cover came off.

I have seen 6Kw units that were single phase 120 output units, not split phase. Not that there would EVER be confusion in terminology. **COUGHSOLARGENERATORCOUGH** :rolleyes:
 

beckkl

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Oh! The reviews I saw on the MPP and the Growatt were both just two setups in the same box with cables connecting the sets. At least that's what it looked like when the cover came off.

I have seen 6Kw units that were single phase 120 output units, not split phase. Not that there would EVER be confusion in terminology. **COUGHSOLARGENERATORCOUGH** :rolleyes:
The product lines are a complete mess in my opinion. At least they are in the pure off-grid applications. Perhaps my use case is not common, but it seems like every unit (or combination of units) is lacking in some way. The LVX6048 seems to get me pretty close, I just wish I had a 240V generator.
 

beckkl

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So Will's trick with the jumper from his Bigbattery.com review from July of 2020 doesn't work on the LVX version? Bummer! I don't think I've ever seen a 220v split phase generator under about 6Kw which is pretty pricy.
Not sure what the trick was you mention. My issue is that I would like to use my 120V generator to charge the batteries from time to time (using the all-in-on), which I cannot do it seems unless I go with 2 units. That would also allow for a split phase setup, but it has some disadvantages. Namely that each leg would be limited to the a single inverter's output (3K in this case), and I don't get the low frequency inverter. There are options out there, but nothing in the $1500 price range (for 6KW) that I can see.
 

Rednecktek

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I seem to remember that he as playing with the 5048 split phase unit in the video and at one point he tried to plug it into the wall to check out the AC charging and it wouldn't charge because it wasn't 220 split phase, so he threw a jumper between the two hot legs and tricked it into thinking it was 220v. Doesn't sound like that's the case with the LVX version. Sadly our krappy satellite connection isn't fast enough to watch youtube out here. :(

Simplest option seems to be just a 48v battery charger plugged into the generator and connected to the batteries, just like paralleling any other charger. No?
 

beckkl

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I seem to remember that he as playing with the 5048 split phase unit in the video and at one point he tried to plug it into the wall to check out the AC charging and it wouldn't charge because it wasn't 220 split phase, so he threw a jumper between the two hot legs and tricked it into thinking it was 220v. Doesn't sound like that's the case with the LVX version. Sadly our krappy satellite connection isn't fast enough to watch youtube out here. :(

Simplest option seems to be just a 48v battery charger plugged into the generator and connected to the batteries, just like paralleling any other charger. No?
It looks like if you have a 0deg phase angle, that's what you are going to get on the output too. That would be no-bueno. This is from the LV5048 (and 6048) manual:

1633960801323.png
 

Rednecktek

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Bummer. Looks like you're back to the 48v battery charger then. Looks like if it's 0deg in it can't be 180deg out.

Just poking around Amazon it looks like you're dropping between $2800 for a 15a or $300 for a 20a which is still less than the $500+ for a generator that will do 220v, but nowhere near as fast.
 
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