Enphase field MTBF: M190: ~36 Years M215: ~316 Years M250: >357 Years

[RegGuheert]

I updated the original post. Please have a look!

 

[Mothernaturesolar]

Nice work Reg, thanks!

 

[madbrain]

FYI, I have a 40 micro-inverter system with no failures yet.

14 D380s were installed in October 2010 (equivalent to 28 M190s) with Sharp mono 235W panels.
12 M190s were installed in October 2012 with Talesun poly 240W panels, to cover additional load from the Leaf.

Not sure how you would calculate the MTBFs on my system.

https://enlighten.enphaseenergy.com/public/systems/njM38932" onclick="window.open(this.href);return false;

The production numbers the last 4 months have been close to the same.

April 2013 Total: 1.67 MWh
May 2013 Total: 1.73 MWh
June 2013 Total: 1.68 MWh
July 2013 Total: 1.74 MWh

Numbers for previous years (with only 28 panels/inverters)

April 2012 Total: 1.08 MWh
May 2012 Total: 1.26 MWh
June 2012 Total: 1.28 MWh
July 2012 Total: 1.28 MWh

April 2011 Total: 1.07 MWh
May 2011 Total: 1.14 MWh
June 2011 Total: 1.18 MWh
July 2011 Total: 1.29 MWh

My 12 panel addition is only adding about 36% more production where I expected 42% (40 / 28).
Looking at things more in detail (per microinverter), I can see that it's the older Sharp panels that are underperforming, not the new Talesun ones.
I was suspecting microinverter failure, but this is not the case. All 40 micro-inverters are reaching their peak capacity still at various times of the day.
The lower production on about 8 halves of the D380s is strange. I'm afraid it's due to more shading since they happen to go to near 0 production for a few hours a day consistently. I may have to talk to the neighbor about some of his extremely tall and growing palmtrees .
I have looked at temperatures and they aren't the issue at all.
The new panels/inverters are installed in locations that are pretty much immune to shade.

This report contains the detailed energy production for July 2013.
Serial Number

Energy Production (kWh)
121018214691-A 43.5
121018214691-B 47.5
121018214693-A 47.5
121018214693-B 47.6
121018214931-A 45.5
121018214931-B 46.1
121018215085-A 45.3
121018215085-B 45.6
121018215094-A 19.0
121018215094-B 18.6
121018215147-A 46.2
121018215147-B 46.6
121018215155-A 35.1
121018215155-B 34.6
121018215194-A 45.4
121018215194-B 45.9
121018215203-A 47.3
121018215203-B 47.0
121018215234-A 39.1
121018215234-B 39.4
121018215246-A 43.6
121018215246-B 43.3
121018215270-A 46.2
121018215270-B 47.0
121018217926-A 39.4
121018217926-B 45.4
121021251503-A 33.5
121021251503-B 46.0
121124810037 48.3
121124810045 46.4
121124810064 47.1
121124810215 48.2
121124810440 47.5
121124810628 46.7
121124810646 47.8
121124810777 48.3
121124810959 46.3
121124811151 46.1
121124811174 47.6
121124811512 46.0
Total 1,743.3

 

[RegGuheert]

FYI, I have a 40 micro-inverter system with no failures yet.

14 D380s were installed in October 2010 (equivalent to 28 M190s) with Sharp mono 235W panels.
12 M190s were installed in October 2012 with Talesun poly 240W panels, to cover additional load from the Leaf.

Not sure how you would calculate the MTBFs on my system.

https://enlighten.enphaseenergy.com/public/systems/njM38932" onclick="window.open(this.href);return false;

Thanks! Your system has been in my spreadsheet for a while. Please see the entries for San Jose, CA currently in rows 29 and 30. The first one is for the old array and the second one is for your new array. Since there have been no failures to date, you can simply add the two greater-than numbers to see that your system currently has an MTBF >89 years.

The production numbers the last 4 months have been close to the same.

April 2013 Total: 1.67 MWh
May 2013 Total: 1.73 MWh
June 2013 Total: 1.68 MWh
July 2013 Total: 1.74 MWh

Numbers for previous years (with only 28 panels/inverters)

April 2012 Total: 1.08 MWh
May 2012 Total: 1.26 MWh
June 2012 Total: 1.28 MWh
July 2012 Total: 1.28 MWh

April 2011 Total: 1.07 MWh
May 2011 Total: 1.14 MWh
June 2011 Total: 1.18 MWh
July 2011 Total: 1.29 MWh

My 12 panel addition is only adding about 36% more production where I expected 42% (40 / 28).
Looking at things more in detail (per microinverter), I can see that it's the older Sharp panels that are underperforming, not the new Talesun ones.
I was suspecting microinverter failure, but this is not the case. All 40 micro-inverters are reaching their peak capacity still at various times of the day.
The lower production on about 8 halves of the D380s is strange. I'm afraid it's due to more shading since they happen to go to near 0 production for a few hours a day consistently. I may have to talk to the neighbor about some of his extremely tall and growing palmtrees .

I agree there are some issues with your older array. I made notes about what I saw the last two times I updated the spreadsheet. There are either some intermittent problems with a couple of the inverters or there is a reporting problem. You can see it (before the end of this month) by clicking the "This Month's Energy" tab on the old site. But they are all working right now, as noted. If you will send me a PM if/when you replace any of the D380s, I can update the spreadsheet, even after September 3.

I thought that perhaps your new array was on a different roof from the old one. If so, note that you cannot compare the production of those microinverters with the production of the old ones. Also note that the new microinverters have more powerful PV panels connected to them, so you expect a slightly better production. For reference, when I attempt to detect failures, I only look for discrepancies between the Daily, Monthly and/or yearly production within a subarray within a system.

 

[madbrain]

Hi,

https://enlighten.enphaseenergy.com/public/systems/njM38932" onclick="window.open(this.href);return false;

Thanks! Your system has been in my spreadsheet for a while. Please see the entries for San Jose, CA currently in rows 29 and 30. The first one is for the old array and the second one is for your new array. Since there have been no failures to date, you can simply add the two greater-than numbers to see that your system currently has an MTBF >89 years.

Thanks !

I agree there are some issues with your older array. I made notes about what I saw the last two times I updated the spreadsheet.

I see your notes now. you put them on line 30 which is for the newest array, but this one has no issue. Your notes should be on line 30.

There are either some intermittent problems with a couple of the inverters or there is a reporting problem.

There are definitely some reporting problems going on, many of my micro-inverters don't seem to update on Enlighten until the next day or so. This makes it hard to analyze failures in real-time. But they can be analyzed the day after usually.

I thought that perhaps your new array was on a different roof from the old one.

They are on a different roof section, yes, where the panels are mostly flat, whereas the other ones are tilted southeast.

If so, note that you cannot compare the production of those microinverters with the production of the old ones. Also note that the new microinverters have more powerful PV panels connected to them, so you expect a slightly better production.

Right, the new panels are 240W vs 235W for the old ones, but this is a fairly minor difference.

For reference, when I attempt to detect failures, I only look for discrepancies between the Daily, Monthly and/or yearly production within a subarray within a system.

I am not sure how to select subarrays.
When I select one of the specific micro-inverters, then the "power : custom range" view, and "graph", I can click on the graph at the bottom. Sadly this shows the power for the whole array, not the specific micro-inverter ! I think that is a bug in Enlighten.
But on the panel array display above, I can see the specific micro-inverter power at the selected time.

Here is the analysis for the 5094-A half of a D380 :
Aug 20 :
normal until 147W to 0W at 10:10am for 10 minutes. Then back at 147W.
from 159W to 0W at 10:45am until 2:55pm. Then 148W.
Back at 0W at 3pm until 3:40pm. Then 129W and declining until 3:55pm.
Then 0W until 4:05pm. Then 118W and declining normally until the rest of the day.

Aug 21 :
normal until 155W at 10:35am, then 0W. Then 167W at 10:45am.
Then 0W at 10:55am . Then 133W at 11:15am.
Then 0W at 11:35am. Stays at 0W until 3:50pm.
Then 123W and declining normally until the rest of the day.

Aug 22 :
normal and reaches 199W at 11:50am. Then 0W. Then 143W. Then 0W at 12:00 until 12:25.
Then 183W . Then 0W at 12:50pm until 2:55pm. Then 152W and declining normally.

I'm already tired from analyzing so much data for just 3 days on one micro-inverter.
Let alone for years on 8 suspicious micro-inverters.

From the daily total system reports, I can see that production was:

Aug 20 : 50.8 kWh
Aug 21 : 52.2 kWh
Aug 22 : 42.4 kWh

The long 0W events are suspicious. They do seem to happen mostly in peak hours.
The times aren't exactly the same each day but similar. I don't know how much can be attributed to shade and how much to micro-inverter failure.

 

[RegGuheert]

I see your notes now. you put them on line 30 which is for the newest array, but this one has no issue. Your notes should be on line 30.

Fixed.

There are definitely some reporting problems going on, many of my micro-inverters don't seem to update on Enlighten until the next day or so. This makes it hard to analyze failures in real-time. But they can be analyzed the day after usually.

I have a similar issue when I charge the LEAF during the daytime. It typically interrupts communcation with some of the microinverters and the data doesn't get corrected until the next day. Do you often charge during the daytime?

They are on a different roof section, yes, where the panels are mostly flat, whereas the other ones are tilted southeast.

Flatter panels will produce more in the summertime than more tilted panels. You should expect the ones tilted Southeast may produce more in the wintertime.

I am not sure how to select subarrays.

I do not actually select the subarrays, I just mentally consider them separately. It sounds like you are looking at the new enlighten website while I am discussing the old one. If you are logged in, you can ONLY see the new website, so you will not be able to see the same thing I do. I have a link to the old website for your array on my spreadsheet in case that helps. Unfortunately, I think none of us will be able to see the old array in a few days.

The long 0W events are suspicious. They do seem to happen mostly in peak hours.
The times aren't exactly the same each day but similar. I don't know how much can be attributed to shade and how much to micro-inverter failure.

It's not shade. You have at least three pairs that are reporting 0W of power during the middle portion of some days. There is no way I know of to tell if that is a reporting problem or a generation problem. But normally reporting problems get automagically corrected later on.

 

[madbrain]

I have a similar issue when I charge the LEAF during the daytime. It typically interrupts communcation with some of the microinverters and the data doesn't get corrected until the next day. Do you often charge during the daytime?

No, I just about never do that except weekends. But I got lots going on in the house power line including some x10 devices, that I am guessing might disrupt the enphase PLC.

Flatter panels will produce more in the summertime than more tilted panels. You should expect the ones tilted Southeast may produce more in the wintertime.

OK, makes sense.

It sounds like you are looking at the new enlighten website while I am discussing the old one.

No, I was looking at the old site.

It's not shade. You have at least three pairs that are reporting 0W of power during the middle portion of some days. There is no way I know of to tell if that is a reporting problem or a generation problem. But normally reporting problems get automagically corrected later on.

Thanks !

I just spoke to Enphase. They are saying there are issues with my D390s with serial ending 5094, 5155, 5234 and 5246.
The first 3 D380s are also the same that are having production issues. The last one doesn't appear to ever have had any production issue.
I identified also 5270, 7926-a and 1503-a as underproducing, but Enphase says those are shading issues. I will take a closer look.
Enphase will be shipping me 4 replacement D380s. So you can put me in for 8 failures.
They say they are a bit backed up with D380s so they didn't have a date when I might receive them.
I inquired about the lost production insurance, and they said they no longer offer it. I was somewhat surprised they can do that unilaterally.

 

[DaveEV]

Enphase will be shipping me 4 replacement D380s. So you can put me in for 8 failures.
They say they are a bit backed up with D380s so they didn't have a date when I might receive them.

Not a surprise - the D380 seems to be their least reliable model. I would personally prefer to replace them with either M190s (I think they are almost plug and play replacements for the D380), or even better the M215 which appears to be much more reliable. Even better than the M215 would be the M250, though it doesn't appear to be shipping quite yet.

Drawback of the M215 is that splicing it in is a bigger pain because it uses that trunk cable, you'd want to replace a whole string, ideally.

 

[QueenBee]

I inquired about the lost production insurance, and they said they no longer offer it. I was somewhat surprised they can do that unilaterally.

That's sad and lame. I presume they could discontinue it because it was not actually offered in the warranty terms.

 

[madbrain]

drees,

Not a surprise - the D380 seems to be their least reliable model. I would personally prefer to replace them with either M190s (I think they are almost plug and play replacements for the D380),

No, the cabling between D380 and M190 is totally different, they are not plug & play replacements.

or even better the M215 which appears to be much more reliable. Even better than the M215 would be the M250, though it doesn't appear to be shipping quite yet.

I won't be upgrading my existing micro-inverters, I expect them to last the specified 15 years which was the warranty on the D380. After 15 years I may consider upgrading.
If I was to do a second PV addition, I would definitely use the newer micro-inverters. But that may be a while. The CSI program has ended in California, and I would need to upgrade my main panel to add more PV, which would be costly. I may decide to do so before the federal solar tax credit expires in 2016 depending where prices are at then.

 

[madbrain]

That's sad and lame. I presume they could discontinue it because it was not actually offered in the warranty terms.

I don't know. They said the program was discontinued company wide.
They will still cover the labor costs for replacing the micro-inverters on my roof, however.

 

[DaveEV]

Not a surprise - the D380 seems to be their least reliable model. I would personally prefer to replace them with either M190s (I think they are almost plug and play replacements for the D380),

No, the cabling between D380 and M190 is totally different, they are not plug & play replacements.

OK, for some reason I thought they were the same.

or even better the M215 which appears to be much more reliable. Even better than the M215 would be the M250, though it doesn't appear to be shipping quite yet.

I won't be upgrading my existing micro-inverters, I expect them to last the specified 15 years which was the warranty on the D380. After 15 years I may consider upgrading.[/quote]
OK, just mentioning it because there have been people who have replaced all their D380s with M215s after experiencing a high rate of failures. Someone just reported it today - they are having all their 25 D380s replaced after experiencing 5 failures after 2.5 years.

http://community.enphaseenergy.com/enphase_energy_community/topics/my_190s_are_failing_at_an_alarming_rate_is_anyone_else_experiencing_this_problem#reply_12797151" onclick="window.open(this.href);return false;

The failure rate you are seeing seems to be pretty much identical in terms of timing (both systems are about 2-3 years old) but you've seen a higher rate of failures with 4 out of 15 failing.

Personally, I think you got a bad batch and it's only a matter of time before you see another 5 go bad. Once you get to 50% failed in a short period of time, it's going to be easier to just swap them out for a more reliable model. The cost to Enphase can't be much different if they can avoid having to pay to send a crew out multiple times.

 

[madbrain]

OK, just mentioning it because there have been people who have replaced all their D380s with M215s after experiencing a high rate of failures. Someone just reported it today - they are having all their 25 D380s replaced after experiencing 5 failures after 2.5 years.

http://community.enphaseenergy.com/enphase_energy_community/topics/my_190s_are_failing_at_an_alarming_rate_is_anyone_else_experiencing_this_problem#reply_12797151" onclick="window.open(this.href);return false;

The failure rate you are seeing seems to be pretty much identical in terms of timing (both systems are about 2-3 years old) but you've seen a higher rate of failures with 4 out of 15 failing.

Personally, I think you got a bad batch and it's only a matter of time before you see another 5 go bad. Once you get to 50% failed in a short period of time, it's going to be easier to just swap them out for a more reliable model. The cost to Enphase can't be much different if they can avoid having to pay to send a crew out multiple times.

That's really interesting. I may call Enphase again to inquire and see if they are willing to foot the bill for replacing everything.
Certainly I wouldn't do it if it had to come out of my pocket. All the D380 cabling would have to be replaced.
There is also a code issue. With my 200A panel I can only have 40A of solar generation. With 20% derating that is 32A.
With my current 40 micro-inverters peaking at 190W I have 31.66A. Ie. I am maxed out. I cannot add another PV panel without changing my main panel.
I would need to go to a 400A panel, or a different type of 200A panel with bussing where the main breaker can be changed (mine won't allow it).
Going to 400A would be about $3000 expense between installer and PG&E. That is why I decided to stop at 40 inverters, and one reason why I use M190s for my expansion last year, and not M215s - the other being that I found a very good price on the M190s.

The 14 D380s generate 22.16A peak. 28 M215 would generate 25A. If I replaced all D380s with M215 and kept the existing 200A main panel, I would have to cut out about 2.5 to 3A of generation, ie. probably remove 4 micro-inverters. Removing 4PVs would add large ongoing costs for me as my system is sized exactly right and doing so would move me into higher PG&E tiers. I don't think the higher peaks on the remaining PVs would compensate for the disconnection of 4 PVs. I doubt very much Enphase will want to pay for my $3000 main panel replacement just because 5 D380s have failed.

I know eventually I may have to bite the bullet and go to another main panel if I want to add more PV later, but I am trying to avoid that expense at the moment until it is really necessary. If I ever have a second EV or PHEV, then I will definitely want to add, but this is years away.

I entered all the production from every micro inverter into a spreadsheet yesterday from CSV. This is the result. I put a red background for every monthly micro-inverter production that was below 95% of the average.

https://docs.google.com/spreadsheet/ccc?key=0AleSSO_7gwqedDVoa3pYVnZxQ2tqUzY5SGlKSWhBTlE&usp=sharing" onclick="window.open(this.href);return false;

As you can see, the production loss has not been large until the last few months. Most of the micro-inverters with the intermittent failures were still producing about 90% of the average until recently when some went to about 50% in june. If you look in the "lifetime" column, there are only 4 inverters that are doing below 95% production of the average of the system.
And only two of these, 121018215094-A and 121018215094-B, are considered failed by Enphase and will be replaced. The other 2 identified as below 95% are actually shading issues.
6 other micro-inverters are being replaced, but they have still been performing fairly well on a lifetime basis, above 95% of average.

I have had 4 D380s fail out of 14. That is a 28% failure rate. One issue may be that my original PV installer (no longer in business) installed everything flush against the roof, without any space.
For my expansion, I used a different installer who installed them a few inches off the roof (may 8 to 10") which certainly will extend the life of the M190s.

Edit: if Enphase was willing to replace all 40 micro-inverters (both the non-failing M190s and the D380s) with M215s, which have longer lifetime and higher production, then perhaps I wouldn't mind paying a little bit out of pocket to replace my main electrical panel and make it all work. I doubt they will do that somehow, though. I have just talked with their tech support and they said that is handled by their escalation team.

 

[madbrain]

OK, just mentioning it because there have been people who have replaced all their D380s with M215s after experiencing a high rate of failures. Someone just reported it today - they are having all their 25 D380s replaced after experiencing 5 failures after 2.5 years.

http://community.enphaseenergy.com/enphase_energy_community/topics/my_190s_are_failing_at_an_alarming_rate_is_anyone_else_experiencing_this_problem#reply_12797151" onclick="window.open(this.href);return false;

I looked at the thread and not seeing the part where they replaced the D380s with M215s. Just that all 25 D380s were replaced.

 

[RegGuheert]

http://community.enphaseenergy.com/enphase_energy_community/topics/my_190s_are_failing_at_an_alarming_rate_is_anyone_else_experiencing_this_problem#reply_12797151

Thanks for that link, drees! There are some unhappy M190 and D380 owners and installers out there. Amazingly, one of the posters in that thread is the owner of the system in Fort Valley, VA, which is the worst-performing system in my spreadsheet. I only ran across that system because it was within about a 50-mile radius of here where I focused my search. Now we have a bit more detail about that system:

Folks,

My array consists of 33 Canadian Solar 230w panels with M190 microinverters. The system went live in June 2011. My first M190 failure occurred in March 2012. As of today I've replaced 12 M190 inverters in my array. I should receive a replacement inverter today for failure # 13, and I just put in a ticket for failure #14. Two of the replacements were "replacements" from earlier.

I didn't put in for reimbursement costs until this Spring when I had four inverters fail. I just put in for reimbursement for one of the recent failures and was denied (owner/installer).

My array is located on the roof with three rows of 11 panels. I have the panels spaced 1 inch apart all the way around. To replace one inverter on either the top row or the bottom row, I need to take up the bad inverter panel and the panel next to it to disconnect the pigtail. If I have to replace one of the inverters in the middle row, I need to take up three panels. Not an easy task!

When I installed the array, I didn't think I would have to replace any of the inverters. If I were still installing today, I would design the array so there is room to work between rows or do ground mount only.

Enphase support has been great at sending the replacement inverters. I'm disappointed that there is no reimbursement for replacement now. I'm also concerned about the failures. There will come a time when I cannot get on the roof to replace an inverter.

I'm curious on the failure rate of the M215? If it is significantly lower (or non-existent), I'd consider pulling all the panels and replacing the M190s with M215s. Yes, I know I'd have to run the trunk line for the M215s.

If Enphase offered a "trade-in/swap" credit (M190s for M215s) to offset the cost of the M215, that would be even better!

Eric

drees, it appears that you may have responded to the above post (as Dave R). Any chance you can send him our way so we can learn more about his system?

 

[QueenBee]

There is also a code issue. With my 200A panel I can only have 40A of solar generation. With 20% derating that is 32A.
With my current 40 micro-inverters peaking at 190W I have 31.66A. Ie. I am maxed out. I cannot add another PV panel without changing my main panel.
I would need to go to a 400A panel, or a different type of 200A panel with bussing where the main breaker can be changed (mine won't allow it).
Going to 400A would be about $3000 expense between installer and PG&E. That is why I decided to stop at 40 inverters, and one reason why I use M190s for my expansion last year, and not M215s - the other being that I found a very good price on the M190s.

Odd, what part number is the service panel you have?

Obviously replacing it with one that either has a 225 amp bus and a 200 amp main breaker or a main breaker that can be downgraded would be cheaper than going to a 400 amp panel.

 

[DaveEV]

OK, just mentioning it because there have been people who have replaced all their D380s with M215s after experiencing a high rate of failures. Someone just reported it today - they are having all their 25 D380s replaced after experiencing 5 failures after 2.5 years.
http://community.enphaseenergy.com/enphase_energy_community/topics/my_190s_are_failing_at_an_alarming_rate_is_anyone_else_experiencing_this_problem#reply_12797151" onclick="window.open(this.href);return false;

I looked at the thread and not seeing the part where they replaced the D380s with M215s. Just that all 25 D380s were replaced.

Doh, you're right. I wonder if I saw that somewhere else or if I'm just imagining things...

Anyway... continuing on that hypothetical because it's interesting...

There is also a code issue. With my 200A panel I can only have 40A of solar generation. With 20% derating that is 32A.
With my current 40 micro-inverters peaking at 190W I have 31.66A. Ie. I am maxed out. I cannot add another PV panel without changing my main panel.

Yes, that would be an issue, especially considering that you have 235W panels which can exceed 190W pretty easily under some conditions. 28 M215 + 12 M190 = 34.8A which is 2.8A which would technically bump you up to a 45A (or 50A is 45A is not readily available) for backfeeding into the main panel.

You'd have to lose either 4 M190s or 3 M215s.

I wonder if Enphase can software limit the maximum power with a firmware update so that the M215s are limited to the same maximum power as the M190 - 0.8A nominal instead of 0.9A nominal)?

Do all of your panels point in the same direction? I have heard of people succesfully arguing for a lower limit circuit breaker so they could install more panels/inverters since not all of them would be hitting peak power at the same time so there would be no issue of nuisance trips - but it looks like all your panels are facing the same direction right now.

One issue may be that my original PV installer (no longer in business) installed everything flush against the roof, without any space.
For my expansion, I used a different installer who installed them a few inches off the roof (may 8 to 10") which certainly will extend the life of the M190s.

Heat could be an issue - but I doubt it's the real reason your D380s have failed. There really seems to be some sort of issue with the D380s - just by reading the Enphase community board, the D380s seem to have the highest rate of failures. M190s seem to be generally good unless you happened to get yours out of a bad batch where they can also have high failures rates. The M215s seem to be very good with only very rare failures.

 

[RegGuheert]

Amazingly, one of the posters in that thread is the owner of the system in Fort Valley, VA, which is the worst-performing system in my spreadsheet. I only ran across that system because it was within about a 50-mile radius of here where I focused my search. Now we have a bit more detail about that system:

I did a little Googling and found this article about Eric Guthrie's system.

Looking at the article, I see a couple of things which are interesting:

- The array is installed on a metal roof on a barn.
- This is a self-installed system, like mine.
- In the article, Eric mentions grounding in a discussion related to potential problems:

Maintaining the system so far has been easy, and he can do the majority of the maintenance himself, checking the panels' progress on the Internet and diagnosing issues.

"If anything it would be a grounding issue." Or a connection issue between the inverters and panels. On his laptop screen Guthrie can view every panel connected to the system.

If I combine this with the knowledge that the inverter that failed on our roof failed during a time when our system was completely ungrounded, I wonder if the issue with Eric Guthrie's system and others could be due to either a grounding issue or installation on a metal roof or both. Perhaps the Enphase M190 inverters are very sensitive to improper grounding. I also wonder about some of the other systems I see in WV since three of the ones with very high failure rates were installed by the same company. Perhaps these all have a common problem in how they are grounded or perhaps they are also located on metal roofs.

In any case, I do not think Eric Guthrie's failures are the result of a bad batch of inverters, since two of the failures were on inverters that had previously failed.

I may give Eric Guthrie a call and discuss his installation with him further.

P.S. My family has now decided to call me the "Solar Stalker!" :lol:

 

[TonyWilliams]

I've had zero failures of the M190's in two years.

I'm mounted on a wood truss roof with tar paper and Spanish tiles. The panels have a LOT of room for air underneath, where the inverters are.

Plus, it never gets brutally hot here (up to about 90F-ish in the summer, but typically 70F - 80F).

My system is properly grounded with a metal rod in the earth.

 

[madbrain]

Queenbee,

Odd, what part number is the service panel you have?

Obviously replacing it with one that either has a 225 amp bus and a 200 amp main breaker or a main breaker that can be downgraded would be cheaper than going to a 400 amp panel.

I don't know, but several solar contractors have told me I need a new main panel to add more PV capacity beyond what I got.
If I was going through the trouble, I would probably go to a 400A feed and panel, though.