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Long term experience with inverter?

Jan Broz

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Nov 10, 2020
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8
Hi,
I'd like to buy some 230V inverter about 2000-3000 W for my off-grid system. Something with reasonable price but with long-term quality. Does anyone have experience with this one or another one?

Thanks :)
I don't think anything you buy that is made in China from aliexpress is going to have long term durability.
 
I don't think anything you buy that is made in China from aliexpress is going to have long term durability.
I don’t know if that’s entirely true
But I would not buy this item.

The price is enough to say “it could be decent” but it’s so low that I’m thinking ‘nah. wouldn’t buy.’

On the ‘inexpensive’ end of things in that price range Giandel on amazonian is probably more money but a lot of people have had good experience with the brand.
If money is manageable but a top brand, or buy two Giandel units and keep the second NIB for Justin- Justin Case.
 
do yourself a favor over the long run any of the major brands will work and last. they are major brands at this point as they made the effort to provide proper warranties, long lasting products, with a minimum of DOA units. non grid tie units that are good to go are for the upper tier: Magnum, Schneider, Outback, Victron. One level down and yet still nice is older xantrex and samlex. I have not tried anything below samlex to comment on. currently I have three magnums, two 48 volts units for whole cabin power. One 12 volt unit for camper with one smaller Samlex for small loads. I have one Xantrex that i got used to play with and it has been pretty solid as well.

one big thing you need to ask yourself: High frequency or Low frequency. HF inverters use lots of mosfets running around like coked up chipmunks. LF inverters use a big honking transformer coil and lots of Mosfets that are idling along not stressed out. the difference is that LF inverters can handle huge surge loads to start hard to start items. (well pumps, A/C units, air compressors, table saws, drill presses etc.) HF inverters are fine for electronics and general lighting as well as smaller refrigerators, but not big compressors like A/C for instance. this will greatly affect your purchase costs as LF are more expensive. it's a you get what you pay for thing. no joke and not stumping for any particular brand, but the established long term brands really are what you want. I will say that most folks I have spoken with or met with campers/boats agree that Aims inverters are hot garbage and rarely make rated power without frying. Thats why they are sub 1k inverters.
 
Out of the AIMS line - they make a few that are ETL (e.g. as good as UL - certified components) - https://www.aimscorp.net/search.php?mode=search&page=1&keep_https=yes

I went with AIMS 12,000w ETL. To date (aprox 2 years) - a total of 15,565hrs of operation producing 36,131kwh of power - no problems so far. Time will tell....
not saying you cannot occasionally win with one, but way more stories of failed units. especially when using it when you should be using a LF inverter.

Edit: If I located the correct model, then yours is a low frequency inverter. apples and oranges. three or four years ago they did not offer any LF inverters, only the craptastic HF ones that toasted constantly. thats why their reputation is toast among a lot of folks, buyer not knowing whats what, and company often not standing behind warranty or at best fighting over the warranty.

I think a lot of it is expectations and people not understanding the difference between a LF and HF inverter. they see the same watt rating and assume that brand B is just overpriced compared to brand A not realizing that there is a major difference. Hence my reference to deciding which he or she actually needs.

I have a HF inverter the samlex, but I use it for what it is intended for charging a laptop a cell phone or a battery tool charger where I don't want to fire up the Magnum.

Flip side I would not buy a 6kw HF to power a compressor based appliance when i can get a 2kw LF inverter to do it and it will be more reliable. in reality they both put out the same just one surges to 6 kw for startup and the other well struggles with its nameplate rating.

I was (and still am) considering using a cheaper HF inverter like Aims to power a water diversion heater system simply because they are cheap, and can easily be toggled off and on via a relay so that it only runs when I hit full charge on the batteries as indicated by the SCC and or BMS and or Primary Inverter system.

The thought was if it did fry I would be out a couple of hundred for a 6Kw model and as there is no motor to start I can put it on a circuit to slow the initial inrush of a water heater and recapture some energy at the end of the charge cycle. so they have their uses but you need to be clear about the actual performance parameters and your intended use.
 
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He says, to a forum filled with people using Chinese batteries and BMS electronics.

But yeah I wouldn't trust an inverter.
I know a strange dissconnect/dichotomy from all of us on this subject right? maybe experience has taught us a bit about Chinese inverters and quality control... or it could bite us all in the backside on the batteries and BMS...only time will tell.
 
I know a strange dissconnect/dichotomy from all of us on this subject right? maybe experience has taught us a bit about Chinese inverters and quality control... or it could bite us all in the backside on the batteries and BMS...only time will tell.

I installed my 11kW solar system in 2017 and spent the previous 2 years researching everything I could before doing it. I'm also a retired electrical engineer, but my expertise has nothing to do with solar or inverters.. or batteries for that matter.

I am a member of pretty much every solar website forum and probably most of the groups on facebook.

I say this because, even though I have almost no experience with Chinese products of this nature, I have paid close attention to the experience of others.

What I have learned is that SMA (German) products are the heavyweight champs.. Right below them are all the popular names like Outback, Midnight, Magnum, Schnieder, Victron, etc.

While it is common to find forum group postings asking questions about these products, such questions are usually due to user ignorance of the menu's, settings, and other options. And while it does happen, it is very rare to see a failure with these products.

On the flip side of this coin are the hundreds of failures I have seen with the Chinese brand products. Some are better than others, but none hold a candle to the list above. Youtube and solar forums are filled with one type of failure or another.

If you buy a Chinese brand inverter, folks need to remember to cut all the ratings by about 50%. If you get a 4000 watt unit and you want to frequently run it at 3000 watts, your reliability statistics are going to tank. On the other hand, that same 4000 watt unit will do just fine with occasional 2000 watt loads.
The problem is that even a 500 watt load can burn out some of these cheaper units with manufacturing quality defects. You won't find these kinds of problem with good inverters like the list above.

Trying to get a Chinese product warrantied is also a problem.

Everyone has to valuate their own requirements. As for us, we live in the rural countryside where the grid goes down every couple of months for up to a week at a time, and if the world goes to $hit, I want my inverter to be reliable.

Someone else who just wants something for camping might not have the same requirements.
 
I installed my 11kW solar system in 2017 and spent the previous 2 years researching everything I could before doing it. I'm also a retired electrical engineer, but my expertise has nothing to do with solar or inverters.. or batteries for that matter.

I am a member of pretty much every solar website forum and probably most of the groups on facebook.

I say this because, even though I have almost no experience with Chinese products of this nature, I have paid close attention to the experience of others.

What I have learned is that SMA (German) products are the heavyweight champs.. Right below them are all the popular names like Outback, Midnight, Magnum, Schnieder, Victron, etc.

While it is common to find forum group postings asking questions about these products, such questions are usually due to user ignorance of the menu's, settings, and other options. And while it does happen, it is very rare to see a failure with these products.

On the flip side of this coin are the hundreds of failures I have seen with the Chinese brand products. Some are better than others, but none hold a candle to the list above. Youtube and solar forums are filled with one type of failure or another.

If you buy a Chinese brand inverter, folks need to remember to cut all the ratings by about 50%. If you get a 4000 watt unit and you want to frequently run it at 3000 watts, your reliability statistics are going to tank. On the other hand, that same 4000 watt unit will do just fine with occasional 2000 watt loads.
The problem is that even a 500 watt load can burn out some of these cheaper units with manufacturing quality defects. You won't find these kinds of problem with good inverters like the list above.

Trying to get a Chinese product warrantied is also a problem.

Everyone has to valuate their own requirements. As for us, we live in the rural countryside where the grid goes down every couple of months for up to a week at a time, and if the world goes to $hit, I want my inverter to be reliable.

Someone else who just wants something for camping might not have the same requirements.
I keep hearing of SMA... are they really that good? Just curious living in japan the only thing you hear about here is "power tite" and they are simply rebranded Samlex or Cotek, kind of depends on when you bought it and what size as too which it is.

Everything else is some CCP hot garbage. I had to research for several years back around 2010 before I built my camper and its PV system and inverter. At that time after a lot of research and browsing I settled on Magnum and Morningstar and have not been disappointed in either choice.

when I started my cabin I just bounced up to their largest offerings and other than the AGM's I started with have never had an issue. just wished they offered a larger inverter, or the ability to stack the non PAE series.
 
A good measure of quality and reliability as well as support would be the warranty they offer. Cheap/unreliable ones will have 1 or 2 year, quality ones come standard with 5 year.
 
I keep hearing of SMA... are they really that good?

About 17 years ago when grid-tie was being done in California with CEC rebates, reports were published giving specs for all of them.
Thousands of systems, > 50% were SMA Sunny Boy. < 50% were divvied up among 20 or so other brands.

SMA used to give 5 year warranty, now 10 years is standard, 20 year optional for grid tie inverters


Battery inverters, 10 years


They are quite reliable, but I have had failures. I put in five SWR-2500U 17 years ago. One blew a PCB trace and board was replaced under warranty, kept working after that. One blew a power transistor, maybe in 10 years? I took it down. Other three no problem. Two failures in 78 inverter operating years, so 39 year MTBF. Oh, one other failure: one stopped operating and I found a kludge circuit, wire tack-soldered to an IC to connect GFCI circuit popped off. I stuck it back on. So make that 26 year MTBF. Obviously retrofitting existing stock to meet new building codes, but that wasn't reliable like normal assembly.

I recently swapped them out to get other functionality. A couple more GT inverter years with no failures, and as for Sunny Island 5 battery inverter years no failures. That brings my total SMA experience to 28 years MTBF.



SMA even powers a small nation

 
I keep hearing of SMA... are they really that good? Just curious living in japan the only thing you hear about here is "power tite" and they are simply rebranded Samlex or Cotek, kind of depends on when you bought it and what size as too which it is.

Everything else is some CCP hot garbage. I had to research for several years back around 2010 before I built my camper and its PV system and inverter. At that time after a lot of research and browsing I settled on Magnum and Morningstar and have not been disappointed in either choice.

when I started my cabin I just bounced up to their largest offerings and other than the AGM's I started with have never had an issue. just wished they offered a larger inverter, or the ability to stack the non PAE series.
Yup.. SMA is really that good. Even their warranty is crazy good.

My list of quality solar stuff could have included Morningstar, but I was trying to make a point not create any "approved list". Morningstar makes good stuff.. very reliable.

As for your batteries, I also became quite familiar with all the various chemistries before building my 25 kWh off-grid system. My advice is to stay away from AGM's and use a flooded battery or a lithium battery if you're going to be off-grid.

AGM's are great, they have some really nice benefits, but their drawback is that they don't last as long as flooded lead acid do. Roughly compared with all other things being equal, an AGM will have 30% to 50% less life than an equivalent flooded cell.

And on that note, if you're going to use a lead acid battery, stick to Rolls or Trojan.. the are the "SMA" of batteries
 
About 17 years ago when grid-tie was being done in California with CEC rebates, reports were published giving specs for all of them.
Thousands of systems, > 50% were SMA Sunny Boy. < 50% were divvied up among 20 or so other brands.

SMA used to give 5 year warranty, now 10 years is standard, 20 year optional for grid tie inverters


Battery inverters, 10 years


They are quite reliable, but I have had failures. I put in five SWR-2500U 17 years ago. One blew a PCB trace and board was replaced under warranty, kept working after that. One blew a power transistor, maybe in 10 years? I took it down. Other three no problem. Two failures in 78 inverter operating years, so 39 year MTBF. Oh, one other failure: one stopped operating and I found a kludge circuit, wire tack-soldered to an IC to connect GFCI circuit popped off. I stuck it back on. So make that 26 year MTBF. Obviously retrofitting existing stock to meet new building codes, but that wasn't reliable like normal assembly.

I recently swapped them out to get other functionality. A couple more GT inverter years with no failures, and as for Sunny Island 5 battery inverter years no failures. That brings my total SMA experience to 28 years MTBF.



SMA even powers a small nation

I thought cool, then I went into those links.... just how much does a 6K SMA cost in the states. becasue for the price of one here in japan I can afford to have 6 of the MS-PAE 4448... (that's me buying in the states and shipping to the base i work at...so no import taxes and no crazy ass Japanese markup.) I have not found out yet what the warranty period is but if its like Snap-On Japan its not worth what the stateside warranty is. will have to research a bit more.
 
Yup.. SMA is really that good. Even their warranty is crazy good.

My list of quality solar stuff could have included Morningstar, but I was trying to make a point not create any "approved list". Morningstar makes good stuff.. very reliable.

As for your batteries, I also became quite familiar with all the various chemistries before building my 25 kWh off-grid system. My advice is to stay away from AGM's and use a flooded battery or a lithium battery if you're going to be off-grid.

AGM's are great, they have some really nice benefits, but their drawback is that they don't last as long as flooded lead acid do. Roughly compared with all other things being equal, an AGM will have 30% to 50% less life than an equivalent flooded cell.

And on that note, if you're going to use a lead acid battery, stick to Rolls or Trojan.. the are the "SMA" of batteries
I started out with AGM's in my camper and they just died at the 10 year mark. That's why i initially went with AGM's for my house. I got right at about 3 years of daily use and they petered out during last winter. shipping FLA batteries to Japan is very, very pricy as they are considered hazmat.

I just commissioned my first lithium bank thee weeks ago and have been fighting the Daly fight as I like to call it. finally got a Daly to work correctly but it was a struggle.

Just got a quote for another 32 cells so I will have 40Kw when finished which is twice what I had with the AGM's. One good thing is that shipping for the batteries is I think quite a bit cheaper than to the states and the import duties are much easier to deal with as they trans-ship from singapore vice mainland china so there are various discounts.
 
I thought cool, then I went into those links.... just how much does a 6K SMA cost in the states. becasue for the price of one here in japan I can afford to have 6 of the MS-PAE 4448... (that's me buying in the states and shipping to the base i work at...so no import taxes and no crazy ass Japanese markup.) I have not found out yet what the warranty period is but if its like Snap-On Japan its not worth what the stateside warranty is. will have to research a bit more.



I'd say 3 of MS-PAE 444

I think Japan has multiple voltages in different regions so make sure your PV system is compatible with appliances.

SMA Sunny Island has a Europe version for 220V and US for 120V. Each of those can be set within some range. Frequency can be 50 Hz or 60 Hz.
That doesn't mean all settable ranges work, it appears they have firmware bugs. Somebody in another location was going to use 120V 50 Hz, and apparently some of the functions involving frequency shift to regulate GT PV inverters are known to not work. SMA must not have thoroughly verified the code.

European Sunny Island is now a newer model, no mechanical breaker or SD card slot.

The MSRP is quite high, US $5000 or so for 5750W continuous. And it takes two for 120/240V split phase, unless you use a transformer. Current passing to/from grid is limited to 56A by relay rating, which is half as many watts at 120V as 220V. The product is optimum match to grid and Sunny Boys for 220V single phase in Europe, not 120/240V in US.

I was going to do single SI-5048US with transformer, and switch some Sunny Boys and load from grid to island during power failures. But due to DC solar bankruptcy, lots of inventory was liquidated. I think some units sold for 10% of MSRP at the original auctions. I paid 25% for pallet of SI-6048US on eBay. A few listings recently at 50% but right now nothing under $3000.

The DC solar trailers with 2x SI-6048US and 2x GNB forklift batteries are still a decent deal if the batteries are healthy.


If I paid MSRP for 2x SI-6048US and 2x SB 6.0-US that would be $15,000. With 4x SB 6.0-US (to make maximum system of 12kW battery & 24kW PV inverter), $20,000.

I installed four SI-6048US wired 2s2p just because I got a deal. More inverter than I need, but serves as a larger transfer switch. I also bought a pallet of Sunny Boy.


Back to quality, some people have run Trace or other inverters for 20 to 30 years, so SMA isn't the only one with known durability.
 
For someone in Europe or other 220V single phase area,
one Sunny Island 6kW and two Sunny Boy 6kW each would be about $10,000 MSRP.
Grid tie, grid-backup, or off-grid it would support 12 kW daytime loads, 6 kW nighttime, 11kW starting surge, 12 kW to/from grid or generator.
Not cheap, but a decent value.
 
thats what I thought, they only offer a 5.5kw unit here with all documents in Japanese. knowing Japan i would guess that it is probably in the range of about 10K per unit. while that is a guess, it is a well educated guess, and they list no prices on the website. so for what it costs i could actually buy 4-5 of the PAE4448 units from NAWS for the price of one. they (SMA)do offer a 15 year warranty with a 20 year warranty if you pay extra here in japan.

regardless ordering one of the SMA units from the states would be a PITA as its over the allowable shipping weight for USPS and the PAE4448 just does clear that hurdle. I even shipped one back for repair after a lightening strike took out the main board.
 
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