Enphase inverter MTBF calculation thread

2

Comments

  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Enphase inverter MTBF calculation thread
    andyman wrote: »
    I'd attach a picture if I knew how but my enphase M190 exploded. Installed in 2011. So MTBF ? 2 years roughly. I also replaced 2 other inverters already. When I say exploded, I mean the case split in half and it ripped one of the bolts apart. Black dust under my panels and thru one of the holes in the inverter.
    3 rd Icon from the left, it's called " Insert Image ". 3 years and not a problem here I had to deal with. The question is, did they replace it and was the shipping Free back and forth to Petaluma ?? Did you find it or did they send you a E-mail and tell you there was a problem ??

    I did have one throw a GFI fault when they up-graded something in the software, they re-set it and it's never happened again. They sent me a email and told me about it. If you had a Installer listed they may be the one getting your e-mails and not responding to them. Generally you can tell on the enlighten interface, if Enphase has done anything about a fault they will Red X in on the interface at the top and the panel will be outlined in Red.
    .
  • andyman
    andyman Solar Expert Posts: 32
    Re: Enphase inverter MTBF calculation thread

    Attachment not found.Attachment not found.Attachment not found.

    There ya go. They haven't shipped anything out yet because i just discovered this last night but my past dealings with enphase is that they will ship out the unit with a return label. So no cost to me. My envoy wasn't hooked up to the internet but will be very shortly. It seems without the envoy , the whole process is a pain because it boils down to who they believe. But they are a very supportive company so I think I should be ok. As soon as I move the envoy into a DMZ at home I will grant it internet access.
  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Enphase inverter MTBF calculation thread
    andyman wrote: »
    Attachment not found.Attachment not found.Attachment not found.

    There ya go. They haven't shipped anything out yet because i just discovered this last night but my past dealings with enphase is that they will ship out the unit with a return label. So no cost to me. My envoy wasn't hooked up to the internet but will be very shortly. It seems without the envoy , the whole process is a pain because it boils down to who they believe. But they are a very supportive company so I think I should be ok. As soon as I move the envoy into a DMZ at home I will grant it internet access.
    Wow, that was a massive failure for sure. I don't now if that a common failure or not, if it's not I am sure they will analyze it. The envoy is the key to the way they have their business model set up. Without it, you don't have much. If you'v been two years without it set up then they have been nice.

    Just a guess, with 3 going out, you have some kind of a issue, the Envoy will tell them what.
  • andyman
    andyman Solar Expert Posts: 32
    Re: Enphase inverter MTBF calculation thread

    Overall I agree with you, which is why I'm setting up the envoy and putting it back into service. I just agree with their methods. a VPN tunnel into my house to collect data? Wheres the search warrant! But at the end of the day they are helping me so I will open it up in the DMZ network. Still , its just a total invasion of privacy. Oh and the failures are in different branch circuits so I doubt its related. I probably just received a bad batch of inverters. Seeing as these things only cost $100 now days I'm not overly concerned. I could just replace all of them if I was really worried.

    I now sit on a spare unit or 2 in case enphase goes out of business.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Enphase inverter MTBF calculation thread

    Not sure--But that does not look like a very rugged box or have much heat sinking potential...

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Enphase inverter MTBF calculation thread
    BB. wrote: »
    Not sure--But that does not look like a very rugged box or have much heat sinking potential...

    -Bill
    It's only 199 watts of power at max output, how big does it have to be ?? They are about 6 " x 8 " x 1 ".
  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Enphase inverter MTBF calculation thread
    andyman wrote: »
    Overall I agree with you, which is why I'm setting up the envoy and putting it back into service. I just agree with their methods. a VPN tunnel into my house to collect data? Wheres the search warrant! But at the end of the day they are helping me so I will open it up in the DMZ network. Still , its just a total invasion of privacy. Oh and the failures are in different branch circuits so I doubt its related. I probably just received a bad batch of inverters. Seeing as these things only cost $100 now days I'm not overly concerned. I could just replace all of them if I was really worried.

    I now sit on a spare unit or 2 in case enphase goes out of business.
    I think all my Serial Numbers run in a sequence, series of 35, not to say everyones would, but knowing the ones that fail would be helpful if what your thinking it true, a bad run.

    I have a extra one also, a just in case.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Enphase inverter MTBF calculation thread

    I was just looking for environmental sealing, mounting strength, corrosion resistance after 20+ years, heat sinking (~6-10 Watts)... The outer cover (5 sides) is not that heavy... The "base" looks like it may be heavier material and provide the heat sinking needed.

    I would guess that the produce is potted--So that the metal housing on some of the sides is less critical (RF Shielding, UL safety Grounding, control of flaming bits -- if it ever were to happen, etc.) -- so the "can" on the out side may not need much thickness.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Enphase inverter MTBF calculation thread
    BB. wrote: »
    I was just looking for environmental sealing, mounting strength, corrosion resistance after 20+ years, heat sinking (~6-10 Watts)... The outer cover (5 sides) is not that heavy... The "base" looks like it may be heavier material and provide the heat sinking needed.

    I would guess that the produce is potted--So that the metal housing on some of the sides is less critical (RF Shielding, UL safety Grounding, control of flaming bits -- if it ever were to happen, etc.) -- so the "can" on the out side may not need much thickness.

    -Bill
    The case is a .050 aluminum die formed and telescoping, Anodized, it is potted with something black. Based on that picture it can be breached in some way, something to think about. That case shows some corrosion, kind of like galvanic corrosion or a lot of water getting on it. I raised one of my panels the other day after 3 years and they looked as new.

    Andyman, not to be critical, but how do you have them mounted ?? The approved way is the rail is about a 9-12" from the top and bottom of the panel and inverter mounts on the back side of the top rail, the Inverter is about in the middle of the panel . I guess with some mounts they would be exposed. That one looks like the water pooled on the bottom side of the inverter.
    .
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Enphase inverter MTBF calculation thread

    0.050" is thicker than it looked on my computer screen... Does not sound like it should be an issue.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Rick1
    Rick1 Registered Users Posts: 24
    Re: Enphase inverter MTBF calculation thread
    RegGuheert wrote: »
    The purpose of this thread is to attempt to create an independent calculation of the Mean Time Between Failures (MTBF) for Enphase inverters operating in the field. If you are unfamiliar with the concept of MTBF, please read Enphase's Reliability White Paper on this topic. Enphase is currently claiming an MTBF of 331 years.

    I believe that there is a fairly significant and growing number of Enphase inverters represented by the posters here, so the idea is to create a list of those inverters and calculate our MTBF or at least the amount of time we have operated without any failures. I will start the list in this post, but if I did not include your system, please post and provide a link to your system. We can then update the tally occasionally to find out how things are going.

    Of course we also need to keep track of failures. Since Enphase claims that infant mortalities are done after two or three weeks, let's be generous and ignore all failures (and not accumulate time) during the first month in service for all inverters. But beyond that, please report ANY failure that has resulted in the need to replace an inverter.

    So here are the systems that I know about so far on this site (I tried to create a table, but this site does not seem to support tables):

    System Link|Quantity|Service Entry Date|Years|Total Years|Failures
    RegGuheert|42|01/2011|0|0|0
    mr.radon|45|10/2010|0.25|11.25|0
    Peter V|15|06/2010|0.5833|8.75|0
    Ralph Day|52|07/2010|0.5|26|0
    drees|18|04/2010|0.666|12|0
    neelix|16|06/2010|0.5833|9.33|0
    jcgee88|15|07/2010|0.5|7.5|0

    (Of course we may need to drop some of these systems if the posters never return and we have no way to find out if there were any failures.)

    So far that comes to an MTBF of greater than 75 years, assuming that none of us have had any failures so far. Not bad. Let's see what it comes out to with more data!

    System Link|Quantity|Service Entry Date|Years|Total Years|Failures
    Rick1/46 M215s/04/10/2012/1/1/00
  • jaggedben
    jaggedben Solar Expert Posts: 230 ✭✭
    Re: Enphase inverter MTBF calculation thread

    I recently saw one that was exploded like Andy's. First time I've seen that, in a year of doing service replacements. My assumption is that a capacitor inside exploded, quite possibly nothing to do with how rugged the box is. IOW, if the capacitor exploded and nothing (except maybe gasses) escaped from the box, then it's rugged enough.
  • andyman
    andyman Solar Expert Posts: 32
    Re: Enphase inverter MTBF calculation thread

    The enphase is mounted properly and done to specifications. The entire system sites on a unirac rail system which is more then 20 inchs off the roof. The roof is a high insulation PV membrane (IB proof brand pvc membrane). The inverter itself sits at the same angle as the panels so water pooling is impossible. I am in san francisco so fog does cause things to corrode, especially aluminum that isn't anodized. I would presume that if the inverter were designed for outdoor use, that it would be able to survive rain and fog.
  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Enphase inverter MTBF calculation thread
    andyman wrote: »
    The enphase is mounted properly and done to specifications. The entire system sites on a unirac rail system which is more then 20 inchs off the roof. The roof is a high insulation PV membrane (IB proof brand pvc membrane). The inverter itself sits at the same angle as the panels so water pooling is impossible. I am in san francisco so fog does cause things to corrode, especially aluminum that isn't anodized. I would presume that if the inverter were designed for outdoor use, that it would be able to survive rain and fog.
    That sounds good enough, hard to tell from a picture. It just looks a lot different from mine. Then again mine are not exposed to the same elements yours are. If they weren't designed to withstand the outside environment then they are in worse shape then I thought they were.
  • RegGuheert
    RegGuheert Solar Expert Posts: 102 ✭✭✭✭
    Re: Enphase inverter MTBF calculation thread
    andyman wrote: »
    I'd attach a picture if I knew how but my enphase M190 exploded. Installed in 2011. So MTBF ? 2 years roughly. I also replaced 2 other inverters already. When I say exploded, I mean the case split in half and it ripped one of the bolts apart. Black dust under my panels and thru one of the holes in the inverter.
    Wow! That's a lot of failures!

    Thanks for the pictures. Can you tell us where you live?

    Please post the public URL to your Enlighten website when you get that up and running and I will add your system into the spreadsheet.
  • drees
    drees Solar Expert Posts: 482 ✭✭✭
    Re: Enphase inverter MTBF calculation thread
    andyman wrote: »
    Seeing as these things only cost $100 now days I'm not overly concerned.
    Where are you getting these for $100? Are these the M190 or M215? At least in my search it seems that the M215 costs about the same as the M190 once you price in the cost of the branch cable...
    andyman wrote: »
    I now sit on a spare unit or 2 in case enphase goes out of business.
    This has been a concern of mine - I don't think they are making money yet, are they?
    That case shows some corrosion, kind of like galvanic corrosion or a lot of water getting on it. I raised one of my panels the other day after 3 years and they looked as new.
    If aluminum isn't anodized, it will look as in the pic after some time in the weather. Don't know if the Enphase inverters are anodized or not.
    http://www.sullivansolarpower.com/about/solar-power-blog/daniel-sullivan/dangers-of-micro-inverters who claim to have 1000s of installations overall, so if they are seeing problems with "all" of the microinverter installations, that sounds like a big deal to me. But that claim is hard to square with the data in this thread...
    They really seem to be stretching the truth there. 150F operation is not a big deal for electronics - they just have to be designed to operate in those kinds of conditions if you want them to last.
  • andyman
    andyman Solar Expert Posts: 32
    Re: Enphase inverter MTBF calculation thread

    Not sure what my enlighten website is, I recently plugged in the envoy to my network so there may not be much to report (maybe a weeks worth of data from). Origninal install date was 2 years ago. By the way, enphase just shipped out a replacement unit. Which is awesome.

    Secondly, I regret to post this but another unit exploded. Same failure as the picture. Hoping to get that unit replaced. I live in San Francisco, CA. I purchased all my equipment thru my installer who purchased it from authorized resellers. One thing I am glad about is that with microinverters, atleast I can swap it out myself easily while leaving most of the system functioning. I don't think I can say the same with central inverters. With that said, I will continue to support enphase when I install solar in my 2nd home.

    When I say I can buy them for $100, I'm talking about ebay.. And that would only be for the temporary backup units.


    andy




    RegGuheert wrote: »
    Wow! That's a lot of failures!

    Thanks for the pictures. Can you tell us where you live?

    Please post the public URL to your Enlighten website when you get that up and running and I will add your system into the spreadsheet.
  • drees
    drees Solar Expert Posts: 482 ✭✭✭
    Re: Enphase inverter MTBF calculation thread
    andyman wrote: »
    When I say I can buy them for $100, I'm talking about ebay..
    I see a bunch of 208V 3-phase units up for $115-120, but no single phase 240V units. I guess those can be used at the end of a string if I understand properly, but do the single phase 240V inverters show up often? I haven't looked much...
  • jaggedben
    jaggedben Solar Expert Posts: 230 ✭✭
    Re: Enphase inverter MTBF calculation thread
    drees wrote: »
    I see a bunch of 208V 3-phase units up for $115-120, but no single phase 240V units. I guess those can be used at the end of a string if I understand properly...

    That last bit is correct. Also, its conceivable that you could either cut and re-wire the cable, or fashion an adaptor cable from an Enphase 3-phase extension cable, and thus essentially turn the 208V inverter into a 240V.

    Of course, any of those things could put your Enphase warranty at risk, especially if the Envoy picked up the serial number and reported it to Enlighten.
  • drees
    drees Solar Expert Posts: 482 ✭✭✭
    Re: Enphase inverter MTBF calculation thread
    jaggedben wrote: »
    That last bit is correct. Also, its conceivable that you could either cut and re-wire the cable, or fashion an adaptor cable from an Enphase 3-phase extension cable, and thus essentially turn the 208V inverter into a 240V.

    Of course, any of those things could put your Enphase warranty at risk, especially if the Envoy picked up the serial number and reported it to Enlighten.
    Well, not to mention that after that amount of futzing, you might as well spend another $20-30 on a new 240V M190...

    I see some 208V units on eBay for $99.95 now. Seriously tempted to buy 2 to add to the end of my existing 2 strings! I know of at least one case where a 208V M190 was used on a 240V system as a replacement (wrong one got shipped out on accident and label wasn't noticed until after it was installed) and Enphase didn't have an issue with it, from what I know the 208/240V M190s are identical aside from the cables.

    I wonder why all these 208V units are showing up on eBay?
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Enphase inverter MTBF calculation thread

    In Northern California, most (all?) of the small office parks are wired 120/208 VAC. We are pretty much crashing in the commercial rental markets out here--Perhaps the expected market for roof top commercial solar did not pan out?

    Also, for commercial utility accounts (from what I little I understand/know), GT solar is not near as good of "deal" as it is for residential.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • NeedMoreSolar
    NeedMoreSolar Registered Users Posts: 23
    Re: Enphase inverter MTBF calculation thread

    you can add my array.
    NeedMoreSolar |40|4/13|0|0|0
    I am adding 10 more in a few weeks I already have the M215’s
  • brasche
    brasche Registered Users Posts: 2
    Re: Enphase inverter MTBF calculation thread

    Add me to the list.

    Initial system was 6300 watts, 30 M210 inverters, 30 Sanyo 210W panels, installed Sept 2009. Added 4 Sanyo 225W, M210 inverters in 2011. Total 7200 Watts.

    This spring three inverters started reporting DC GFI faults and going off line. Resetting the flag would work for a while, but they would eventually GFI again. I reported it to Enphase support and a week later they were sending two replacements. Since then the third got worse and they replaced it, along with another inverter that would periodically report "DC power too low" and go off line, sometimes two or three times a day. Now Enphase is sending yet another replacement for an inverter that was reporting "grid gone" and "critical temperature" but still producing, which after a firmware update to v1.08, is now reporting "DC power too low" all day. All the failed inverters are from the original installation. For 4.5 years the system was rock solid, then a couple of months ago things went south. I'm thinking firmware updates have something to do with it. My system stability deteriorated the day v1.07 was installed (June 13, 2014.)

    That's 5 of the original 30 that have been replaced.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Enphase inverter MTBF calculation thread
    brasche wrote: »
    Add me to the list.

    Initial system was 6300 watts, 30 M210 inverters, 30 Sanyo 210W panels, installed Sept 2009. Added 4 Sanyo 225W, M210 inverters in 2011. Total 7200 Watts.

    This spring three inverters started reporting DC GFI faults and going off line. Resetting the flag would work for a while, but they would eventually GFI again. I reported it to Enphase support and a week later they were sending two replacements. Since then the third got worse and they replaced it, along with another inverter that would periodically report "DC power too low" and go off line, sometimes two or three times a day. Now Enphase is sending yet another replacement for an inverter that was reporting "grid gone" and "critical temperature" but still producing, which after a firmware update to v1.08, is now reporting "DC power too low" all day. All the failed inverters are from the original installation. For 4.5 years the system was rock solid, then a couple of months ago things went south. I'm thinking firmware updates have something to do with it. My system stability deteriorated the day v1.07 was installed (June 13, 2014.)

    That's 5 of the original 30 that have been replaced.

    Welcome to the forum.

    I do hope your experience is not evidence of our initial doubt about Enphase inverters standing up to being located outdoors under panels in all kinds of weather. Although I would not be surprised if it were. Five years to failure is far short of their 15 year estimate.
  • DanS26
    DanS26 Solar Expert Posts: 264 ✭✭✭
    Re: Enphase inverter MTBF calculation thread

    If we could only talk to the accountants, not the engineers, we could evaluate the real situation about the warranty problems. The CPA's setting up the warranty reserve accounts have very strict guidelines to follow.

    Looking at the 2013 FY 10K financial statements.....2013 Revenues increased 7.5% over FY 2012 but warranty reserves were increased 67.0%.......red flag if I have ever seen one.....
    23.16kW Kyocera panels; 2 Fronius 7.5kW inverters; Nyle hot water; Steffes ETS; Great Lakes RO; Generac 10kW w/ATS, TED Pro System monitoring
  • massey4
    massey4 Registered Users Posts: 2
    Warren|34|07/2010|5|170|8 which is not a particularly good record. The panels are all Sanyo HIP-215NKHA5's (72 cells, VOC=51.6). The inverters are all the M210s. The entire array is split into an eastern-facing half and a western-facing half (the roof ridgeline runs north/south). Electrically, the array is made up of two AC strings of 11 panels each and one AC string of 12 panels and so far all the failures have been in the one string of 12 which is entirely in the eastern grouping of panels. I am glad to say that no replacement inverters have failed so perhaps the replacements are better than were the originals. With all the failures in a single AC string, it makes me wonder if there is more than just coincidence at work here. But I wouldn't think that the inverters would be sensitive to the AC current daisy-chained through them and certainly the inverters that have failed out near the end of the chain are less stressed in this respect than are those near the heads of the chains in the other AC strings. All the failures have occurred on the eastern-facing side of the roof which I would expect to run a bit cooler (indeed more failures happen early in the solar season (spring) than at any other time) but the eastern array does deliver a bit more power per panel on the average so it may be working a bit harder. A second AC string has 7 eastern-facing panels and 4 western-facing panels and it has not experienced any failures. I find it interesting that the M210s were the only inverter Enphase made (until only very recently with the new C250) that could handle a 72-cell panel so I suspect they found that the engineering behind the M210's was not what it needed to be and they had to put a fair amount of work into reengineering them.
  • SolarPowered
    SolarPowered Solar Expert Posts: 626 ✭✭✭
    I install roughly 160 enphase inverters per year.
    Within year 2.5 I have 1 failure out of 320 micro inverters installed. Through out northern and Southern California.

    The number being less static to the time of installation roughly shows a mortality rate of 1 in about 250 micro inverters by year 2.

    There are inaccuracies to the mortality rates because of the differences between solar panels either being mono, or poly, which respond to different MPPT algorithms, associated with rates of MPPT clipping, based on level of light insolation, and mono's being more efficient than poly at the lower light levels, including level of cloud cover.

    There are also inconsistencies in the mortality rates between M215 and the M250, depending on the panel wattage selected to meet the efficiency threshold of MPPT algorithm. This falls more under installer/engineering error more so than the micro inverter.

    There are a lot of variables to associate actual mortality rate.
  • jcgee88
    jcgee88 Solar Expert Posts: 154 ✭✭
    Updated numbers for me. No issues at all for me during the first five years
    with M190's, but then three failures within the last couple of months.
    I added eight panels with M215's last year, so the data below reflects my
    original configuration, not my current one (23 total panels).

    Summary of installation:
    7/2010 - 13 M190's, Sharp panels
    1/2011 - 2 M190's Sharp
    5/2014 - 8 M215's Suniva


    System Link|Quantity|Service Entry Date|Years|Total Years|Failures
    jcgee88|15|07/2010|5|74|3
  • PhoebeAnn
    PhoebeAnn Registered Users Posts: 1
    System Link|Quantity|Service Entry Date|Years|Total Years|Failures
    https://enlighten.enphaseenergy.com/pv/public_systems/D8ra464682|40|10/9/2014|1|1|0
    Lousy roof for the system, but you go with what you got. Not quite breaking even until the system is paid for. 1st year's history:


    Really embarassing when the grid is down and I have to fire up the generator on a sunny day, looking for a way to make this system bisexual -- e.g., grid-tied when the grid is up, off-grid/battery when the grid is down (manual switchover OK). Looking lustfully at the Tesla battery as a component in such a system.


  • mastruck
    mastruck Registered Users Posts: 1
    Phoenix, AZ

    70 S280 Envoys
    New install. So, issues yet.
    Phoenix APS 21kW - (70) LG 305 / Envoy S280