GoodWe inverter problems

[Jason W]

I own and operate a small solar design and installation business in Portland Maine and have been in the solar industry since 1999. I am sharing this story about GoodWe in the hopes that I can help other solar installers avoid what I have gone through with GoodWe's faulty inverters. My story is a bit long but it is worth reading if you are concerned about the reputation of your company with respect to the products you sell. The synopsis is this:

• The MS-US inverters inject high frequency waves into the AC output when running at full power, likely due to poor quality filtering on the PWM hardware. This can cause AC breakers to blow if you have more than 4 inverters on the same service.
• The DC arc fault detection algorithm remains a significant concern with the MS-US model.
• The inverter has faulty firmware that causes it to go to zero production if amperage gets higher than about 14 amps per string. You will only detect this if you have multiple units on the same site as it can look like the impact of passing clouds if you only have one unit.
• Power factor cannot be set in the SolarGo app—it has to be done by GoodWe tech support remotely
• The upper end of the MPPT tracking range was moved down from 550 volts to 500 volts because of problems with inverters in the field. At this rating it is impossible to get close to 160% DC oversizing as they claim in the spec sheet without significant operational impacts.
• The internal cooling fan, which was never mentioned in the original spec sheet (now listed in the updated spec sheet), is very loud and cycles frequently.
• The units have very low quality WiFi transponders that frequently lose connection and will send annoying alarms on a random basis—won’t send it every time so it is unreliable.
• The SEMS portal data cannot be trusted to update regularly.
• If you have a serious problem with a GoodWe inverter you will be transferred to dealing with “headquarters” which will be difficult unless you speak Chinese. They will also use the time difference between the countries and “Chinese Holidays” as excuses for their delays in solving problems.
• The U.S. Division of GoodWe has very little authority to solve technical problems and no authority to approve things as simple as an inverter RMA so you may be thinking you are dealing with a U.S. company when you buy their product but in fact the U.S. Division is under-resourced and is required to consult with headquarters in China for most important customer support functions.

If you go to the attached documents you can get all the details that support my assertions listed above

 

[ggunn]

I own and operate a small solar design and installation business in Portland Maine and have been in the solar industry since 1999. I am sharing this story about GoodWe in the hopes that I can help other solar installers avoid what I have gone through with GoodWe's faulty inverters. My story is a bit long but it is worth reading if you are concerned about the reputation of your company with respect to the products you sell. The synopsis is this:

• The MS-US inverters inject high frequency waves into the AC output when running at full power, likely due to poor quality filtering on the PWM hardware. This can cause AC breakers to blow if you have more than 4 inverters on the same service.
• The DC arc fault detection algorithm remains a significant concern with the MS-US model.
• The inverter has faulty firmware that causes it to go to zero production if amperage gets higher than about 14 amps per string. You will only detect this if you have multiple units on the same site as it can look like the impact of passing clouds if you only have one unit.
• Power factor cannot be set in the SolarGo app—it has to be done by GoodWe tech support remotely
• The upper end of the MPPT tracking range was moved down from 550 volts to 500 volts because of problems with inverters in the field. At this rating it is impossible to get close to 160% DC oversizing as they claim in the spec sheet without significant operational impacts.
• The internal cooling fan, which was never mentioned in the original spec sheet (now listed in the updated spec sheet), is very loud and cycles frequently.
• The units have very low quality WiFi transponders that frequently lose connection and will send annoying alarms on a random basis—won’t send it every time so it is unreliable.
• The SEMS portal data cannot be trusted to update regularly.
• If you have a serious problem with a GoodWe inverter you will be transferred to dealing with “headquarters” which will be difficult unless you speak Chinese. They will also use the time difference between the countries and “Chinese Holidays” as excuses for their delays in solving problems.
• The U.S. Division of GoodWe has very little authority to solve technical problems and no authority to approve things as simple as an inverter RMA so you may be thinking you are dealing with a U.S. company when you buy their product but in fact the U.S. Division is under-resourced and is required to consult with headquarters in China for most important customer support functions.

If you go to the attached documents you can get all the details that support my assertions listed above

Thanks for the warning.

 

[solarken]

Yes, thanks for sharing. I wish there was a forum to discuss issues we experience with different products and manufacturers so that we can help make all of our systems better and maybe apply a little pressure to the manufacturers to support us better knowing we are not suffering in individual silence.

 

[Zee]

Thanks for the heads up!

Sorry for your experience.
(I count myself lucky as I was taught to stick to SMA inverters. At least until recently.
Fronius and Xantrex were tried - but not reliable enough. Especially the blue/silver Fronius.
Heck those are GREAT compared to many others.)

I am relocating to New England, where you seem to be. How is the solar insdustry up there? It might be interesting for us here as its not the most common area we here from!

In particular, I see almost all the houses look the same there, old boxy New England homes........ and have no overhangs, wood siding and importantly, steep roofs.
How do you handle the steep roofs? Do you own scaffolding, sub it out, or ropes? Or....?

 

[Zee]

If you have time, I wouldnt mind a pic or 2 of your installs.
So many different ways to install PV...... always good to learn.

 

[electrofelon]

Here in New York State, due to the new UL1741 supplement B requirement, the only string inverters we can use are Solis or Goodwe. Fantastic, two choices, both Chinese, good job guys . I have not used goodwe/badwe, and we only have four solis inverters installed so far. I'm on the verge of going to all micros because of this. Strings have still been a significant money saver for ground mounts, but I'm very uncomfortable with these communist inverters.

 

[jaggedben]

It boggles my mind that SMA doesn't have a UL 1741 SB inverter.

 

[electrofelon]

It boggles my mind that SMA doesn't have a UL 1741 SB inverter.

My statement was based on about a year old information. I did just rescheck the list form the NYS public service commission, and there are quite a few other string inverters on there now. A couple more communist ones (lux and growatt), TIGO has some, Sonnen, fronius has updated their primo line and they are on there.......but yes strangely no SMA single phase inverters, just a couple three phase.

 

[jaggedben]

I guess the single phase market almost entirely uses MLPE for rapid shutdown so they don’t consider it worth the the testing fees? Still kinda baffled.

 

[Zee]

SMA led for 10 years and has fallen behind for past 10 years. At least in the USA vis a vis RSD. I want to use theirs, but it has gotten hard to. Took sevral years to roll out new resi inverters....and only offered as hybrid battery versions at 2x the cost of others.

 

[ggunn]

It boggles my mind that SMA doesn't have a UL 1741 SB inverter.

That confuses me; I thought that all PV inverters these days were designed to UL1741.

 

[electrofelon]

That confuses me; I thought that all PV inverters these days were designed to UL1741.

The latest revision is supplement B and seems to be taking a while for everyone to get on board

 

[ggunn]

What is in Supplement B?

 

[electrofelon]

What is in Supplement B?

This is not the first you have heard of it gunny, see here where in post #5 on JUNE 17th 2023 you said that was the first you heard of it

UL 1741-SB

Go ahead and tell me I've had my head in the sand or have been living under a rock, thats fine - I have only been doing a couple PV systems per year for the last 6 years. So I go to submit the paperwork for this summer's two systems and I find out that both utilities are requiring inverters...

forums.mikeholt.com

 

[ggunn]

This is not the first you have heard of it gunny, see here where in post #5 on JUNE 17th 2023 you said that was the first you heard of it

UL 1741-SB

Go ahead and tell me I've had my head in the sand or have been living under a rock, thats fine - I have only been doing a couple PV systems per year for the last 6 years. So I go to submit the paperwork for this summer's two systems and I find out that both utilities are requiring inverters...

forums.mikeholt.com

Well, it isn't the first time I have had to be reminded of a question I have.... just a minute... HEY! You kids get off my lawn!

What was I saying?

 

[electrofelon]

Well, it isn't the first time I have had to be reminded of a question I have.... just a minute... HEY! You kids get off my lawn!

What was I saying?

Well I don't know about you, but UL1741SB isn't the most exciting topic out there, so I don't blame you for forgetting .


But since it came up, just curious how is the adoption going in other states? Anybody else having to comply with requirements for supplement B compliant equipment now?

 

[jaggedben]

Yes, the equipment has to be certified, even if nothing is done about it after that. So far this is no more consequential than picking the right entry in a list on the online connection portal. We only use Enphase which was pretty much at the forefront of this so it's been very inconsequential for us. (They did come out with a new version of the Envoy with a hardware difference, but I don't know what the difference actually is. Hopefully the stock of older envoys went to other states.) I would imagine that someone out using another brand of inverter there has lied on an interconnection application to get it through, and as long as the AHJ doesn't look past the brand of inverter they might get away with that.

The same goes for UL1741SA, which might actually matter a bit more under certain grid conditions. The inverter had to be capable of it but no one is checking if it's enabled properly. Well, I bet the utility is checking on some big systems, but not on resi under 30kW.

 

[analog8484]

Well, I bet the utility is checking on some big systems, but not on resi under 30kW.

Have you seen any data on this? I doubt the POCO's are actually using the advanced (i.e. out of band) comms/controls on resi systems at all.

 

[jaggedben]

Have you seen any data on this? I doubt the POCO's are actually using the advanced (i.e. out of band) comms/controls on resi systems at all.

Actually I was only even talking about SA, which is automonous dynamic response with no utility control. As far as data, I mean, I've not seen any from the utilities or state but as far as the systems my employeers have installed (all resi in that time period, with PG&E) I've seen zero spot checking of enforcement of either set of requirements. It's basically honor system with a bit of a check through the AHJ permit approval that you installed a capable inverter. That the SA or SB functions are actually enabled is totally honor system on resi systems AFAIK. As I said I would be surprised if they weren't checking this stuff on megawatt systems, but I don't work on those. Maybe the other major IOUs are doing something that PG&E isn't (I certainly wouldn't expect the vice versa on that).

 

[electrofelon]

Have you seen any data on this? I doubt the POCO's are actually using the advanced (i.e. out of band) comms/controls on resi systems at all.

I don't have any data, but round here (upstate). NY the closest the POCO comes to looking at a resi solar system is the guy who installs the net meter. You could have a bunch hamsters spinning a wheel with a generator on it and they will never know.