Safety hazard w/ Growatt 5000ES (European version) when connected to American grid

[sunshine]

If you read it carefully it seems to say that the company SGS tested it and they say it is up to UL standards.

SGS

UL

Absolutely lost but what do companies have to do to say it is up to UL standards?
Do they consider the whole unit or go down to the component level?

From the 2 links- UL can test UL467 Electrical Grounding and Bonding Equipment. This is not listed for SGS.

Somewhere in there must be a listing for AIO units, or is the manufacturer allowed to cherry pick which testing lab they send their units to?....a company that doesn't test UL467 would be my choice if I have concerns regarding my product.

 

[Hedges]

I've seen a product get through UL certification at another NRTL.
They reviewed specs and schematics, conducted various tests on accessible voltages and surface temperatures.
Components themselves generally didn't need to be listed parts, but if data sheet describes the part as a "fuse" then they look for that.
Do to convoluted design process, most of the PTC fuses in my DC circuit (about 50 mA supply and 20 ma fuse) were UL listed but one wasn't, and they objected. I found a footprint compatible part which was listed.
They also visited assembly house.
With all concerns addressed, they issued their certification for the product.

I think the process can catch a number of hazards, and would confirm operation of features such as UL-1741 anti-islanding, but hazards could slip by either by oversight or things like code bugs that make operation compliant or not depending on inputs and state.

 

[Bud Martin]

I've seen a product get through UL certification at another NRTL.
They reviewed specs and schematics, conducted various tests on accessible voltages and surface temperatures.
Components themselves generally didn't need to be listed parts, but if data sheet describes the part as a "fuse" then they look for that.
Do to convoluted design process, most of the PTC fuses in my DC circuit (about 50 mA supply and 20 ma fuse) were UL listed but one wasn't, and they objected. I found a footprint compatible part which was listed.
They also visited assembly house.
With all concerns addressed, they issued their certification for the product.

I think the process can catch a number of hazards, and would confirm operation of features such as UL-1741 anti-islanding, but hazards could slip by either by oversight or things like code bugs that make operation compliant or not depending on inputs and state.

I have surprise visit by the UL inspector all the time, he will grab the unit off the final assembly and inspect all the critical components (I.E. Fuse, circuit breaker, AC outlets, wires, insulation sheet, transformer, etc) as listed in the report, if I have to change the parts due in shortage then I have to submit the new part spec that has UL compliance and pay UL to update the report, plus we pay yearly due to keep the certificate active until the product is no longer produce, UL makes a lot of money.

 

[Hedges]

When all you have is a hammer ...
He can detect substitutions by you of a different part number, but not by a supplier who selects a different part to rebrand and sell to you.
And he has no idea if your last software feature or bug fix broke compliance (unless he runs a checksum)

 

[Struc]

Any chance this thread could get back on topic? ?‍

 

[Hedges]

Any chance this thread could get back on topic? ?‍

You have the 5000ES according to your signature?
Can you check with meter and report if it isolates but Neutral and Line from AC input, or not?

 

[Struc]

You have the 5000ES according to your signature?
Can you check with meter and report if it isolates but Neutral and Line from AC input, or not?

Not to be rude, but read page 1 where I stated exactly that. Will also confirmed with Signature Solar that all of their units are not bonded.

 

[Hedges]

Not to be rude, but read page 1 where I stated exactly that. Will also confirmed with Signature Solar that all of their units are not bonded.

Your comment on first page:

"I'm not saying I know anything about anything, but I just pulled my Growatt SPF5000ES out of the box, and I have NO connectivity between ground and the marked Neutral (L2 for our use), either input or output.

I have a somewhat hard time believing that, if it were true, that nobody would have caught onto it by now, or even found out by accident.

How can you have a dead short between L2 and ground, and these things aren't blowing up all over the place everywhere?"

My question was not whether Ground was bonded to Neutral.

My question is whether Neutral (AC input) is always connected to Neutral (AC output), or if it gets disconnected by a relay.
A single-phase inverter might have Neutral hardwired, and a single pole disconnect isolating Line (AC input) from Line (AC output). That is how my Sunny Island (120V US model) is wired.

I'm sure Sunny Island (220V European model) also has a single-pole relay that only isolates Line, not Neutral. So I don't think it could be used in the US across L1, L2. At least not unless isolation transformers were used in grid side AC input and island side AC output.

So I'm trying to determine if this Growatt has 2-pole isolation or single pole isolation.

 

[dweick]

I keep saying it, there is no way a Growatt with a transformer is going to pass an electrical inspection unless your lucky enough that your cousin is the inspector. Then your second issue is always going to be an electrical fire breaking out. Once the fire dept traces the fire source back to the inverter your insurance company has a free get out of payment Pass.
BTW Growatt UL Certified!
I just do not believe it.

I've asked everyone I've seen claiming insurance companies don't pay because you screwed something up if they can quote from their policy where it says that, still waiting for someone to find the language. Really wish people would stop with the insurance fear mongering and stick with just telling people what they are doing is a bad idea and why.

 

[rfbuehler]

I’m planning 3 SPF5000ES in parallel (15kw) and totally off grid. I will interlock the main breaker with the Off Grid breaker in my load panel. That way I’m either on grid or off grid, no middle ground. I will have a 4th 3000ES tied to a 5K genset that will fire up if batteries go to low. It’s whole reason in life is a battery charger. I my utility room I will have lighting off the main load panel and this 3000ES that way I will never be in the dark.

As long as the N and Ground are isolated I should have no issues?????

 

[Struc]

My question was not whether Ground was bonded to Neutral.

My question is whether Neutral (AC input) is always connected to Neutral (AC output), or if it gets disconnected by a relay.
A single-phase inverter might have Neutral hardwired, and a single pole disconnect isolating Line (AC input) from Line (AC output). That is how my Sunny Island (120V US model) is wired.

My apologies for that... you are correct.

Keep in mind this unit is brand new, never powered up. I do not have any ability to test for a relay. My test is unpowered, out of the box new.

That said, I'm seeing 1.74 Megaohms between "N" on the input and output. Seeing 2.6 megaohms between the two "L" terminals.

One interesting thing to me is that the A/C Input side ground is what is grounding the case.
The A/C output ground is not connected to the case nor in any way connected to the input ground.

 

[Bud Martin]

BTW, if you look inside your unit, is the grounding screw removed as shown in the video? if it is removed, do you see any kind of insulator sheet installed between the PCB and the chassis when the screw is? The gap between the PCB and chassis screw post is very small, you may be able to push on the PCB that will cause the connection to be made again between the chassis and the PCB. I hope they do put insulator sheet between PCB and the chassis where the grounding screw is.

 

[Struc]

BTW, if you look inside your unit, is the grounding screw removed as shown in the video? if it is removed, do you see any kind of insulator sheet installed between the PCB and the chassis when the screw is? The gap between the PCB and chassis screw post is very small, you may be able to push on the PCB that will cause the connection to be made again between the chassis and the PCB. I hope they do put insulator sheet between PCB and the chassis where the grounding screw is.

I have not opened the top portion of my unit to check. I would guess if these are built this way by Growatt (which I assume they are), the standoff for that screw would be removed or some other isolation method would be used - not simply hoping an air gap works. Too many of these things out there in production - no way the air gap method would work for all of them.

 

[Bud Martin]

The only way to find for sure out is to open it up, or we can just trust them. Does it also means that these are modified and made specially for US market to be sold by SS but not by WATTS247 since Watts247 still has screw and standoff? I wonder if Will gets the final details about this unit from SS..

 

[Tecnodave]

There is no such thing as UL certified....period....that is an advertising scam.

U.S. NEC states very clearly that the device must be “ listed by a US OSHA NRTL to the applicable U.L. standard”

By listing that means the Nationally Recognized Testing Laboritory had tested all functions and has “listed“ that device in their publicly available data base.

Look at the qualifications of the big name American manufacturers

“Listed by ETL to U.L. 1741SA”

OR

”Listed by U.L. to U.L. 1741SA”

Those 2 NRTL qualification labs are not the only qualified to do testing, European T.U.V. is also a U.S. OSHA NRTL, I do not know of any American manufacturer that uses T.U.V. but there is no reason why they could not.

I have found Chinese manufactured equiptment stating “tested to U.L.” and certified to U.L. This does not have any meaning, It is meant to confuse you into believing that they are code legal here when in fact they are not.

 

[Tecnodave]

I went to the Growatt US site for the SPF 5000 ES and it doesn't list a UL certificate. It only lists EU certifications.

I then did a search for 'growatt' on the UL database. The only thing I found is a rapid shutdown system that was tested with some growatt inverters. I found no UL listed Growatt inverters. (Maybe I need to search on different terms?)

I have searched the California database as well and there are no Growatt units listed there. This is where all California planning departments search for documentation on units for the building departments. The planning department must approve the plans before the building department can issue a building permit here. (California)

 

[Zwy]

I have searched the California database as well and there are no Growatt units listed there. This is where all California planning departments search for documentation on units for the building departments. The planning department must approve the plans before the building department can issue a building permit here. (California)

Look under Rule 21. These GW's are Rule 21 Compliant. http://www.growatt-america.com/upload/file/admin/2020/10/5f8813281af60.pdf

Also, GW models are listed here that are Rule 21. https://solarequipment.energy.ca.gov/Home/InverterBatteryList

 

[Hedges]

Keep in mind this unit is brand new, never powered up. I do not have any ability to test for a relay. My test is unpowered, out of the box new.

That said, I'm seeing 1.74 Megaohms between "N" on the input and output. Seeing 2.6 megaohms between the two "L" terminals.

One interesting thing to me is that the A/C Input side ground is what is grounding the case.
The A/C output ground is not connected to the case nor in any way connected to the input ground.

Hi resistance for "N" between input and output is what I was looking for. That means they are isolated, so won't backfeed into the grid so should be safe.
It must have a relay to connect that when desired, or simply won't work in pass-through mode from grid. (unless it is on-line UPS, AC to DC battery charger with separate inverter, which would also be safe. But probably has relay.)

 

[Hedges]

Look under Rule 21. These GW's are Rule 21 Compliant. http://www.growatt-america.com/upload/file/admin/2020/10/5f8813281af60.pdf

Also, GW models are listed here that are Rule 21. https://solarequipment.energy.ca.gov/Home/InverterBatteryList

I don't find the GroWatt name on the ca.gov site, but I do find "GoodWe Technologies Co., Ltd. GW5000A-ES [240V]"

On the GroWatt site (.pdf) you linked I find "MIN5000TL-XH-US"

 

[Struc]

The only way to find for sure out is to open it up, or we can just trust them. Does it also means that these are modified and made specially for US market to be sold by SS but not by WATTS247 since Watts247 still has screw and standoff? I wonder if Will gets the final details about this unit from SS..

As I stated earlier, I'm certain all of the units that Growatt puts together for the US do not have the bonding screw - although I certainly have no proof of this, but it makes sense. Either way, it is easy enough to verify. If the screw is there, you'll see continuity on a meter between the case and N. Takes about 5 seconds to check.

The problem would come in if you're buying one of these off AliExpress or something. Then you'd have no idea how it's configured until you check.

To all the people still arguing about certification - start your own thread! Geeez