I recently installed a 5KW Goodwe ES inverter with 3KW of panels and a 5KVA battery. Shortly after installing it I lost my 2 fridges, and a chest freezer. 2 of them went and burned out their boards completely as if by a major surge (along with a garage motor charger), and my 17 year old fridge's compressor went 2 weeks later. Insurance paid out for the first two, I replaced the other fridge and the charger out of pocket. I figured it was just bad luck and a big surge but two days ago my brand new upright freezer blew with a loud pop one evening. I need to add I have in 12 years of living in the complex I stay in never lost a major appliance, but have now lost 4 in under 6 weeks. I also checked both times I lost a major device and no one else in the complex of 70+ units lost anything, so that implies it is something wrong with the install in my eyes, not a surge. My installer is adamant that its not the system though and showed me a graph from SEMS portal that showed our input voltage has been fluctuating between 240V and 253V a lot which is on the high side. Can anyone confirm this?

Not sure what to do or how to proceed but I can't keep losing appliances. I eventually got the specialized fridge surge protection plugs that protect against high and low voltage yesterday. No idea if insurance will cover the new freezer which could mean either an expensive repair for me, or at worse a loss of a 10K appliance and significant risk it just continues.

No idea what to do next. Considering getting an independent electrician in to check my installers work but that will cost me, and in my experience most electricians are quick to criticize others work as a matter of principle to rustle up new work for themselves. So if I do get someone else in it would have to be someone very honest and frugal not wanting to do lots of additional work that is not necessary. At this point financially we are pretty tapped out post the install of the system so I don't want to spend too much, but also can't keep losing appliances either. So where do I go from here?

If possible get someone to install a electrical logger.

This will log current and voltage over a period of time. Also see if someone can test all electrical outlets with an earth leakage tester. It indicates if all the wiring in correct.

253V is high but most appliances will be able to cope with it. Most are rates to at least 260V

I agree the 253V is high but should not be damaging. One problem I have seen is that if your inverter output neutral is floating you can get high voltage spikes to earth - effectively line voltage at ~380V but your inverter input won't see this. I would get your sparky to check if the neutral is correctly bonded at the inverter output. The fridge guards should stop future spikes but if there is a problem they will also fail.

Is your grid code set to Warehouse/Default 50Hz?

18 hours ago, Cius said:

I recently installed a 5KW Goodwe ES inverter with 3KW of panels and a 5KVA battery. Shortly after installing it I lost my 2 fridges, and a chest freezer. 2 of them went and burned out their boards completely as if by a major surge (along with a garage motor charger), and my 17 year old fridge's compressor went 2 weeks later. Insurance paid out for the first two, I replaced the other fridge and the charger out of pocket. I figured it was just bad luck and a big surge but two days ago my brand new upright freezer blew with a loud pop one evening. I need to add I have in 12 years of living in the complex I stay in never lost a major appliance, but have now lost 4 in under 6 weeks. I also checked both times I lost a major device and no one else in the complex of 70+ units lost anything, so that implies it is something wrong with the install in my eyes, not a surge. My installer is adamant that its not the system though and showed me a graph from SEMS portal that showed our input voltage has been fluctuating between 240V and 253V a lot which is on the high side. Can anyone confirm this?

RE the voltage fluctuation, it does happen. The numbers will vary from area to area. Where I live the problem was (past tense) low voltage. Especially during times of high demand it could drop down to the 180s, and we almost never saw 230V (then a substation burned down. Since the repairs were done, our voltage has been better). Point is that supply voltage can fluctuate. 

One thing to check is the safety code setting on the inverter. This is displayed in the PV master app and can be changed there. It should be set for South Africa. It then expects 230V plus or minus a bit, and will disconnect when the supply voltage gets too high or too low. When it disconnects, your backed up circuits will get a nice 230V (+- a smidgen) at 50Hz, but your non-backed up circuits will still get whatever is on the grid. 

So two things to understand: What circuits are backed up, and how is the safety code set for your inverter? Then discuss with the installer.

This is the inverter outputting DC. I suspect it only happens when the grid code is set to Default 50Hz, which some installers select because selecting SA grid code caused issues in older firmware.

It should also be noted that by not selecting the SA grid code, the device is also not NRS097 compliant.

Edited September 9, 20223 yr by P1000

This sounds like your Main DB was not split properly or at all. The Neutrals of the Grid & the inverter are not completely split. This is when things go pop, like what you are experiencing. 

Beware the neutrals & the reasons for the main DB split. 

15 hours ago, Steve87 said:

This sounds like your Main DB was not split properly or at all. The Neutrals of the Grid & the inverter are not completely split. This is when things go pop, like what you are experiencing. 

Beware the neutrals & the reasons for the main DB split. 

Normally your explanation would probably be the most plausible, but after a proper review of a site where this happened, I can say with confidence that the GoodWe pushed out DC and took out everything with an induction motor and a transformer. All SMPSs kept on working through the event. No MOVs were damaged. AC fuses arced over and caught fire. All the symptoms could only be explained if the inverter passed through DC.

So an update. I eventually got an independent electrician out and he found no evidence of the neutral split error. He did find that some wires where lower gauge than the trip switches they where on, so I had him replace those. He found two plugs without an earth (due to a dodgy builder I had years ago). Do not use the one plug at all and the other one only has two pin garage motor chargers on it. He also found a few neutral wires that where twisted together rather than bonded via a bridge. I have fixed those issues but just had another fridge go. A brand new Defy. If I even plug it in it trips my earth leakage. It blew while on one of those Ellies fridge protector surge plugs.

Sems portal indicates that input voltage over the weekend has been a bit high. Ranging from 248 to 256V. While this is high I also seem to be the only person loosing major appliances. Have asked on the complex group again and one person noticed a surge at around the time the fridge went but no one has lost appliances other than me over the last while. It still feels like the Goodwe is somehow making the issue worse for me. The installer won't budge and just says its the power situation in the area, not the inverter. I am at my wits end. I have now spent so much money on this problem and rather than having a working system that saves me money it only seems to cost me money.

@Leshen can you not assist this man if he lives close enough

Several other people in the complex have now responded saying they also noticed a surge. No one else reporting lost fridges though. So I can now somewhat confirm its an issue with power in the area. However it seems to hit me harder so I still think the inverter is somehow amplifying the problem. Not sure. Going to try contact CoJ tomorrow to raise our local transformer as an issue.

3 hours ago, Cius said:

It blew while on one of those Ellies fridge protector surge plugs.

Those won't protect against DC.

Go into the PV Master app and change your grid code to South Africa.

Assuming the Grid code is not set correctly, suggestion would be to take photographs as evidence before changing it, in the hope that it helps for something.

Point is, the grid code is a setting that must be input upon installation before connecting to the grid for the first time, as described in the manual.

I think you would need an analyser to really sniff out what is taking place. Unfortunately these machines are not common place & someone who would have one would be highly qualified & probably demand more money to be spent...

I strongly disagree with the suspicion of the Goodwe outputing DC power. If we talking about a cheap clone of some poor quality inverter then yes. A Goodwe, is not a candidate for this. It's quality is renowned & I highly doubt that DC power leaking out of the AC output would just spike sporadically without that Goodwe going into a fault mode of proportions. 

Can you post a picture of the Changeover switch & the wiring thereof. Just remove the cover & take a snap. 

This is highly cryptic & I really feel for your situation, I hope you get a success soon because this is not good to read nor the experience for you of anything more than stressful. 

On 2022/09/10 at 11:54 AM, P1000 said:

Normally your explanation would probably be the most plausible, but after a proper review of a site where this happened, I can say with confidence that the GoodWe pushed out DC and took out everything with an induction motor and a transformer. All SMPSs kept on working through the event. No MOVs were damaged. AC fuses arced over and caught fire. All the symptoms could only be explained if the inverter passed through DC.

Never given thought to such failure mode in the short time ive been exposed to inverter systems.  And ouch 😯 its perfectly possible in transformerless design . Wouldnt occur during transistor failure in the bridge, but it can happen when the controller mcu stalls, leaving one side of the bridge hanging on 400vdc.  Doesnt seem axperts has a watchdog for this. 

And behold if you are grid tied on top of it all when this dc is pushed outside the machine. 

 

EDIT : have you actually been witness to such a  failure before? 

Edited October 9, 20223 yr by BritishRacingGreen
Extra info

4 hours ago, Cius said:

Several other people in the complex have now responded saying they also noticed a surge. No one else reporting lost fridges though. So I can now somewhat confirm its an issue with power in the area. However it seems to hit me harder so I still think the inverter is somehow amplifying the problem. Not sure. Going to try contact CoJ tomorrow to raise our local transformer as an issue.

There is a possibility that grid disturbances and surges may affect the goodwe inverter. These inverters synvhronizes to the grid voltage and phase, and inverter may get disturbed because of this and compounds the problem. 

Question i have, is how do the other consumers noticed the surge if they did not experienced  any damages? 

9 hours ago, BritishRacingGreen said:

have you actually been witness to such a  failure before? 

I have, and you are correct, there was a DSP stall/event. But it seems to only happen when the grid code is misconfigured.

17 hours ago, BritishRacingGreen said:

There is a possibility that grid disturbances and surges may affect the goodwe inverter. These inverters synvhronizes to the grid voltage and phase, and inverter may get disturbed because of this and compounds the problem. 

Question i have, is how do the other consumers noticed the surge if they did not experienced  any damages? 

Just thinking out loud again. Should be careful with that. Way I see it, the inverter should synchronise the grid frequency and phase, but the voltage should be a bit higher than the grid voltage in order to inject power into the grid. Now if as above the grid voltage was going as high as 256V, that's already above the required parameters, and unless the inverter has been set up to protect the load correctly, what are the chances that the guy with the grid-tied inverter was worse off than the rest in the complex?

Other line of thinking, again just posing questions without truly knowing. Goodwe seems to indicate that it is not to be used as a permanent backup for loads with high surging components, if I read correctly they say only 1.5KVA per inductive appliance, and 2.5KVA in total. Would it play any role in damaging the inverter and/or the load if the fridges are on the backed-up side, as opposed to being on the non-essential side. Looking at the manual they seem to show washing mashines should be on the non-essential side, but there's no clear indication of fridges.

So interesting question. In PV Master in the advanced settings, is the inverter set to do full-wave detection or half wave or none? Because if that is not set to full-wave, then it doesn't matter if the inverter is set to South Africa or not.

I have heard of other goodwe installations in SA where full wave detection was not set. On my own inverter, it is set to full wave detection, and every freaking time there is something funny on the grid, it kicks into off-grid mode. What is annoying about this is, then 30 second later the inverter goes into check mode, which kills all the solar generation for 60 seconds, and then its like the MPPT restarts and the solar generation have to rebuild up slowly to full generation. Now imagine this happening every 5-10 minutes. Highly annoying. However I will take this over spikes going through to the backup side and killing fridges.

1 hour ago, Tinuva said:

Because if that is not set to full-wave, then it doesn't matter if the inverter is set to South Africa or not.

Why do you say this? Grid code set to Wharehouse changes a lot of things - and disables a lot of safety features.

14 hours ago, P1000 said:

Why do you say this? Grid code set to Wharehouse changes a lot of things - and disables a lot of safety features.

When its set to none, it doesn't disconnect the grid when there are issues with frequency and/or voltage. What is the point of having it set to South Africa when using none on wave detection? As in what safety features still work in that combination?

Just now, Tinuva said:

When its set to none, it doesn't disconnect the grid when there are issues with frequency and/or voltage. What is the point of having it set to South Africa when using none on wave detection? As in what safety features still work in that combination?

It should still disconnect when the voltage is out of range and also when the grid falls away. In that case it affects the islanding behaviour. It also affects other things like DC injection tolerance and PV safety levels. If it is not set to SA grid, it will not pass an NRS097 test.

I suspect DC injection detection happens on the other DSP, which when set to wharehouse/50Hz default, will not disable the output when the DSP doing the AC inversion stalls and generates DC. But that is only a theory.

I just checked PV master on my phone. The setting that @Tinuvarefers to is "Detection Mode".

It gives three options

1) Full wave

2) Half wave

3) Support voltage ride through.

 

The app tells us that "full wave" provides fast detection of grid overvoltage and undervoltage. Half wave mode provides fast detection of grid undervoltage.

The safety code for my inverter is set to "south africa", but I still can choose  between these detection modes.

Is it possible that if detection mode is not set to full wave, and that there is a surge of high voltage, then the inverter will not disconnect and protect the backed up circuits?

3 minutes ago, Bobster. said:

then the inverter will not disconnect and protect the backed up circuits?

No, wave detection only relates to the time it will take to detect grid loss. The other features are not affected.