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

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RegGuheert said:
ltbighorn said:
As an side, it seems Enphase has started making Envoys only report 15-minute interval failures, down from 5-minute, as a cost saving measure. This results in stair-stepping on the Enphase graphs (and anything that pulls from their API). Very annoying. In order to get 5-minute data back I've had to switch pvoutput from API polling to pushes from my local server polling the Envoy-S. Seems silly. If they want to cost save, they should just reduce the >30 day 5-minute interval data down to 15-minutes. Tiny savings either way, but the storage cost of the long-term data is going to way outsize the last couple weeks of data.
Perhaps I am not understanding what you are saying by "only report 15-minute interval failures, down from 5-minute" as all my data is still available in 5-minute intervals.

Hmm "failures" must have been a cut and paste error. Enphase has been transitioning customer Envoys to only report at 15-minute intervals, reduced from the previous 5-minute intervals. It seems to be a gradual rollout, as different people get converted at different times. I was about 1-2 months after the first user reports I saw, and I've seen others report being switched 4-6 weeks after I was.

A couple users have reported getting Enphase Support to switch them back (I had zero luck with that), but at least some of those have reported that it only lasted a short while and they were converted by to 15-minute reporting intervals again within a few weeks.
 
ltbighorn said:
Enphase has been transitioning customer Envoys to only report at 15-minute intervals, reduced from the previous 5-minute intervals. It seems to be a gradual rollout, as different people get converted at different times. I was about 1-2 months after the first user reports I saw, and I've seen others report being switched 4-6 weeks after I was.

A couple users have reported getting Enphase Support to switch them back (I had zero luck with that), but at least some of those have reported that it only lasted a short while and they were converted by to 15-minute reporting intervals again within a few weeks.
Thanks! That makes sense. Perhaps its time for me to unplug my Envoy from the internet. Of course I'll need it fairly soon to commission the new M250s.
 
RegGuheert said:
Thanks! That makes sense. Perhaps its time for me to unplug my Envoy from the internet. Of course I'll need it fairly soon to commission the new M250s.

If you don't have your own separate metering (or Envoy-S CT-based metering) and get your data by polling the Envoy's 5-minute (soon to be 15-minute) values, and don't care about the Enlighten/API values, then yeah, that might make sense.

Since I have an Envoy-S w/CT metering, I at least have an alternative post-update (note: the firmware version did not change, no outward sign of any updates) way of getting the 5-minute data I want, otherwise I'd be much more upset.
 
ltbighorn said:
RegGuheert said:
Thanks! That makes sense. Perhaps its time for me to unplug my Envoy from the internet. Of course I'll need it fairly soon to commission the new M250s.
If you don't have your own separate metering (or Envoy-S CT-based metering) and get your data by polling the Envoy's 5-minute (soon to be 15-minute) values, and don't care about the Enlighten/API values, then yeah, that might make sense.

Since I have an Envoy-S w/CT metering, I at least have an alternative post-update (note: the firmware version did not change, no outward sign of any updates) way of getting the 5-minute data I want, otherwise I'd be much more upset.
I decided to not disconnect the cable from the internet because that would prevent me from accessing the Envoy through the web interface. Instead, I used my router to block the Envoy from making outgoing connections through the router. This looks just like the internet is down to the Envoy since it cannot tunnel into the mothership. (FWIW, I unblocked UDP port 53 so it could FIND Enphase, but it then is blocking TCP port 443 (https).)

Hopefully this will allow the Envoy to continue to collect data from the inverters every five minutes. I'm thinking I might be able to upload data intermittently without getting the setting change. But what I don't know is whether the servers just wait for the Envoy to connect and then immediately provide the new settings.

Thanks for the heads up on this, guys. We'll see what happens...
 
RegGuheert said:
In spite of the fact that I have experienced one failure of a fourth-generation inverter in the past year and zero failures of the third-generation M190s, I decided to fully divest myself of M190s. I just purchased 12 new 72-cell M250s on eBay for $90 each shipped. This is the cheapest price I have ever paid for ANY Enphase inverters, new or used. These new inverters will replace the 12 M190s that are each connected to pairs of 72-cell, 120W PV modules in the field.

With this change, I expect to see a marginal increase in production in the wintertime since the old inverters spent much of their time saturated at 199W during the cold weather. The bigger benefit of this upgrade is the extension of the warranty period from ending at the close of 2025 to ending in 2042. The field array currently produces about $400-worth of electricity each year. I expect that in 2026, that amount of electricity will be worth about $600, if not more. In 2042, I expect that amount of electricity will be worth at least $800. As such, I expect today's $1080 investment to return about $12,000 between the years 2026 and 2042. If they last longer than that or if electricity gets more expensive than that, it will just be more gravy.
The 12 new M250-72s arrived in great condition in their original packaging on Saturday. The date codes on these inverters are very recent: Week 25 of 2017.

Given the recent date codes and the fact that I purchased these units to extend my warranty coverage on the field array, it makes no sense for me to install them right now. The reason is that Enphase starts the warranty period on the earlier of the date of installation or four months after the product is shipped from their factory. So I will wait until at least late October to install these new units to ensure the warranty runs for as long as possible.

Who knows? Maybe I can even get another M190 failure or two before that time.
 
RegGuheert said:
The 12 new M250-72s arrived in great condition in their original packaging on Saturday. The date codes on these inverters are very recent: Week 25 of 2017.

Given the recent date codes and the fact that I purchased these units to extend my warranty coverage on the field array, it makes no sense for me to install them right now. The reason is that Enphase starts the warranty period on the earlier of the date of installation or four months after the product is shipped from their factory. So I will wait until at least late October to install these new units to ensure the warranty runs for as long as possible.

Who knows? Maybe I can even get another M190 failure or two before that time.
As I had indicated above, I have not yet installed any M250-72s due to the desire to extend their warranty as long as possible. But I have now upgraded the wiring on the field array to allow for the transition from M190s to M250-72s. Once I started working on the wiring, I realized that I can easily accommodate BOTH M190-style wiring AND Enphase Engage wiring. This arrangement allows me to install any arbitrary combination of third- or fourth-generation Enphase inverters on that array.

Given this newfound flexibility, I am now in a bit of a quandary. The M250-72s have a peak production capability which is 612 W higher than that of the M190s (3000 W versus 2388 W). Since the array is ideally pointed during the coldest months, this will mean some additional production when it is lowest. OTOH, the M190s do not limit their output power during the other half of the year. Since my preference would be to keep the hours OFF the M250-72s as much as possible AND I would also prefer to put as many hours on the M190s as possible, I am thinking it may be best to operate the M190s during the summertime between the Spring and Autumn equinoxes when I adjust the array pointing and operate the M250-72s during the other half of the year. The goal is to try to encourage as many M190 failures as possible (to get fourth-generation replacements as spares) while limiting M250-72 failures as much as possible.

I'll probably give this a try during 2018 and see how much of a PITA it turns out to be.
 
RegGuheert said:
I couldn't help myself: I picked up 12 more new 72-cell M250s over the weekend for $85 each shipped. (My wife asked when I intend to stop purchasing $1000 boxes of inverters. ;) ) I figured that since I have nine M250s on my roof with no warranty this would be good, cheap insurance through the end of 2042. I'll probably just keep these new ones in their box and use them only when/if I need to replace something. (I expect to see a little more production from the field array during the wintertime by replacing the old M190s with M250-72s, but I doubt there is any production benefit to be gained by replacing M215IGs with M250-72s.)

FWIW, my MTBF numbers now look like this:

Third-generation microinverters (originally 42 M190s now down to 39 after replacements): 41 years (six failures)
Fourth-generation microinverters (1- M190IG, 29 - M215IGs, 13 - M250s): 85 years (one failure)

I won't start accumulating MTBF data on the M250-72s until I install 12 of them in November.
 
drees said:
ltbighorn said:
As an side, it seems Enphase has started making Envoys only report 15-minute interval failures, down from 5-minute, as a cost saving measure. This results in stair-stepping on the Enphase graphs (and anything that pulls from their API). Very annoying. In order to get 5-minute data back I've had to switch pvoutput from API polling to pushes from my local server polling the Envoy-S. Seems silly. If they want to cost save, they should just reduce the >30 day 5-minute interval data down to 15-minutes. Tiny savings either way, but the storage cost of the long-term data is going to way outsize the last couple weeks of data.
Yes, that was my exact thoughts as well, and frankly, I'm pissed that they didn't properly notify customers when taking away the feature, especially when they don't provide a good way to get the data directly off the envoy.
I just wanted to follow up on this subject since I just upgraded to an Envoy-S over the weekend. What I see in the Installer Toolkit App is that the Envoy-S has a setting known as "Report Setting" which defaults to "Low-Bandwidth", but which can be easily switched to "Standard". The "More Info" provided in the Installer Toolkit App says this:
Enphase Installer Toolkit App said:
This Envoy is set to standard reporting, which typically reports 5-minute interval data to Enlighten every 5 minutes during daylight hours. You may switch to low-bandwidth, which reports 15-minute interval data to Enlighten four times per day.
But then when I look at the settings for the new Envoy-S in Enlighten Manager, this is what I see:

Enlighten_Settings_For_Envoy_SWeb_Communication.png


As you can see, it talks about "...at least every 15 minutes...", but that clearly is referring to the reporting interval, not the interval between data points since the "Low-Bandwidth" setting clearly provides data more often than four times each day.

What I see on Enlighten is that yesterday when the new Envoy-S was reporting in "Low-Bandwidth" mode, each inverter was updated every 15 minutes, but today each inverter is updated every 5 minutes since I switched to "Standard" "Report Setting". As such, it appears that if you an Envoy-S AND have access to Enlighten Manager or the Installer Toolkit, you can set it whichever way you prefer, at least for the time being.

BTW, kudos to Enphase for making it so that the Envoy-S can be added to a system without ever needing to call support. The Installer Toolkit makes things much more straightforward, even if there is NO internet connection available to the system. It updated the Envoy-S immediately from my iPad and then the Envoy-S has been spending its time over the past couple of days updating the firmware on my M250s and M215IGs. It appears that for whatever reason those updates were not happening with the old Envoy. I'm glad to see that since one of my M250s had failed to receive the previous updates that its siblings had received and was still running the original image which it had received in 2013. Now nine of the M250s (the oldest ones) are all at firmware v01.22.00 and some of the M215IGs appear to be getting updated with that version today. (It appears that it has uploaded the firmware, but that it will not request a reboot in the middle of the day while the sun it shining. We'll see what happens...)
 
RegGuheert said:
But then when I look at the settings for the new Envoy-S in Enlighten Manager, this is what I see:

Enlighten_Settings_For_Envoy_SWeb_Communication.png


As you can see, it talks about "...at least every 15 minutes...", but that clearly is referring to the reporting interval, not the interval between data points since the "Low-Bandwidth" setting clearly provides data more often than four times each day.

What I see on Enlighten is that yesterday when the new Envoy-S was reporting in "Low-Bandwidth" mode, each inverter was updated every 15 minutes, but today each inverter is updated every 5 minutes since I switched to "Standard" "Report Setting". As such, it appears that if you an Envoy-S AND have access to Enlighten Manager or the Installer Toolkit, you can set it whichever way you prefer, at least for the time being.
OTOH, when I look at page 30 in the Envoy-S Manual, I see the following verbiage instead:
Envoy-S Manual page 30 said:
Standard
Typically reports 5-minute interval data to Enlighten every 5 minutes during daylight hours.

Low-Bandwidth
Reports 15-minute interval data to Enlighten four times per day.
So it seems Enlighten has been updated to change the wording for the "Standard" "Report Setting".
 
pclifton on December 14 said:
I do have two M190s that are producing about 10 percent less than the other inverters. I suspect it to be the inverter, I do have a couple of spares to swap in at some point.
RegGuheert said:
Who knows? Maybe I can even get another M190 failure or two before that time.
I am about to swap in 12 of my new M250-72-2LL-S22 fourth-generation inverters for the 12 third-generation M190-72-240-S12s which are currently attached to the PV modules in the Field Array. The wiring is now in place to allow either third- or fourth-generation inverters to operate in this array, or both. This change will increase the DC breakdown voltage of the inverters from 56 V to 62 V and will increase the maximum output AC power rating from 199 W to 250 W. Most importantly, it will extend the warranty coverage for these inverters from the end of 2025 to the end of 2042.

Seven of those M190s have been limping along with several daily "Grid Gone" events each day, but they have still managed to produce nearly as much AC electricity as their properly-functioning neighbors. But one of them has only produced about 88% of its neighbors during the month of October, so I decided to call Enphase to see if I can get them to replace it with an M190-72-2LL-S22-IG before I pull the old units out of the system. But no dice. For some reason (and I don't know where I got the information) I thought the threshold for replacement was producing below 90% of a neighboring inverter. But the representative at Enphase informed me that the criterion is actually 80%, not 90%. Oh well. It's not a big deal, but I thought I would give it a try. Now I know what the correct threshold is.

At this point, I think I have enough equipment operating and in storage to keep the entire system operating until about 2050 or beyond. Time will tell.

To this end, I have made the following transactions over the past four years (all prices include shipping):
- Sold 4 M190s for $500.
- Sold 20 M190s for $1000.
- Sold some old Trace Engineering equipment for $2500.
- Purchased 12 M215-60-2LL-S22-IG with plastic cases for $1440. (This purchase was to add the field array to the system.)
- Purchased wiring equipment for the field array for $300. (For Field array.)
- Purchased 4 M250-60-2LL-S22 with metal cases for $508.
- Purchased 9 M250-60-2LL-S22 USED with plastic cases for $1000.
- Purchased 12 M215-60-2LL-S22-IG with plastic cases for $1116.
- Purchased 5 M215-60-2LL-S22-IG with metal cases for $460.
- Purchased Engage cabling and accessories for the House and Garage Arrays for $900.
- Purchased 24 M250-72-2LL-S22 inverters for $2080.
- Purchased a spare Envoy (pill-shaped) for $250.
- Purchased an Envoy-S for $249.
- Purchased on Envoy-S Metered for $192.
- Purchased Engage cabling for the Field array for $250.

Net expenditure for upgrades: $4745 (plus a LOT of effort and fiddling).

For all that, I believe I have accomplished three things:
1) I have brought the old field array, which was originally part of a battery-based system, back into service on-grid. I expect that array will produced over $20,000 worth of electricity during its life (based on an average price of electricity of $0.018/kWh for 30 years).
2) I have extended the life of the arrays on the roof by about 25 years. I expect the electricity produced by those arrays during those additional years will be worth approximately $70,000 (based on an average price of electricity of $0.20/kWh for those additional 25 years).
3) I have GREATLY reduced my need to go onto the roof during future years.

My system will look like this after swapping in the new M250s:

Enphase Envoys:
- 2 - Envoys (pill-shaped) (2 spares)
- 1 - Envoy-S (1 in service)
- 1 - Envoy-S Metered (1 spare)

Fourth-generation Enphase Microinverters:
- 24 - M250-72-2LL-S22 (12 in service, 12 spares)
- 24 - M215-60-2LL-S22-IG with black plastic cases (24 in service)
- 5 - M215-60-2LL-S22-IG with metal case (5 in service)
- 9 - M250-60-2LL-S22 used, no warranty, with black plastic cases and M215 metal plates (9 in service)
- 4 - M250-60-2LL-S22 with metal cases (4 in service)
- 2 - M190-72-2LL-S22-IG still new, with metal cases (2 spares)
- 1 - M190-60-2LL-S22-IG with black plastic case (1 spare)

Third-generation Enphase Microinverters:
- 15 - M190-72-240-S12 (15 spares)

That's a total of 69 fourth-generation inverters and 15 third-generation inverters to cover the 54 locations I have in the arrays. Put another way, 54 inverters in service and 30 cold spares.

2050, here I come! Hopefully we will outlive all this equipment!
 
GetOffYourGas said:
I was chatting with my friend (not a member of MNL) about your spreadsheet, and how I have 4 of 6 known M215 failures. He was intrigued, and gave me permission to give you info to add to your spreadsheet.

His public envoy site: https://enlighten.enphaseenergy.com/pv/public_systems/hNDa25959/overview
Located in Clay, NY
In service since 8/9/2011
Consists of 24x Suntech STP225-20/Wd modules mated with 24 M215 inverters

No failures to date.

Two updates.

My friend has experienced his first M215 failure. I assume his replacement will be an M215-IG like mine, but we aren't sure yet. The unit failed earlier this week (about 10/15).

I am on the brink of having my 5th M215 fail. It is under-producing all of the others, and cuts out in bright direct sunlight. Although it still produces some power, I already consider it a failure, since over the past 7 days, it has produced 711Wh, while the others have averaged over 2kWh each (so it's roughly 35% - well below the spec). I've contacted my installer again, but no word back from him on a replacement.
 
GetOffYourGas said:
Two updates.

My friend has experienced his first M215 failure. I assume his replacement will be an M215-IG like mine, but we aren't sure yet. The unit failed earlier this week (about 10/15).

I am on the brink of having my 5th M215 fail. It is under-producing all of the others, and cuts out in bright direct sunlight. Although it still produces some power, I already consider it a failure, since over the past 7 days, it has produced 711Wh, while the others have averaged over 2kWh each (so it's roughly 35% - well below the spec). I've contacted my installer again, but no word back from him on a replacement.
Thanks, Brian. I'm sorry about your inverter failure. This brings the MTBF for the M215s in your system down to 17.5 years.

You're friend's system has an MTBF of about 150 years right now.

With this update, the M250s have now surpassed the M215s as the Enphase MTBF leader. However, I will add that it has been over a years since I got an update from QueenBee. If he has experienced no failures during that time, then the M215s are still in the lead. QueenBee?

Here are the Enphase microinverter MTBF numbers as I see them right now:
Code:
===============================================
| Inverter |   MTBF  |  No. of  | Max Service |
|   Type   | (Years) | Failures |   (Years)   |  
|==========|=========|==========|=============|
|   M250   |   357   |     0    |     3.6     |
|==========|=========|==========|=============|
|   M215   |   316   |     8    |     6.3     |
|==========|=========|==========|=============|
|  M215IG  |   106   |     1    |     3.5     |
|==========|=========|==========|=============|
|   S280   |    68   |     0    |     1.0     |
|==========|=========|==========|=============|
|   M190   |    36   |   246    |     8.9     |
|==========|=========|==========|=============|
|  M190IG  |     7   |     4    |     3.3     |
|==========|=========|==========|=============|
|   IQ6+   |     ?   |     0    |     0.0     |
===============================================
The M250 reliability numbers are quite impressive in that no failures are recorded after some units have been in service for 3.6 years. I have had both and M190 and an M215IG fail after only about six months in service. GetOffYourGas had his first failure of an M215 after about two years in service. The MTBF of the M190s seems to be fairly well established at about 35 years now, though some customers experienced much worse reliability. It's still a mystery why the M190IGs have such a miserable failure rate. I suspect it may be simply due to bias in the data since one poster came to this forum for the express purpose of reporting his three failures, but I also wonder if not having ground in the adapter cables could be a contributing factor. Finally, we simply don't have enough data yet on the S280s and the IQ6+ inverters to establish an MTBF number.
 
RegGuheert on April 2 said:
More likely the failures in the M190s are due to a solder joint or component which is failing due to thermal cycling. (And I really don't think the electrolytic capacitors are the main culprits at this early stage in the game.)
On page 32 of the presentation Enphase made to stock analysts on June, 19, 2017, they confirmed that the electrolytic capacitors are NOT involved in the top ten failure modes for their microinveters:
Enphase on page 32 of Analyst Day Presentation said:
Enphase has solved the e-cap problem
Enphase on page 32 of Analyst Day Presentation said:
- No degradation after 5 years of operation
- Not in the top 10 failure modes
- Lifetime failures:
-- 9 out of 56 million
-- 0.16 dppm per e-cap
Some thoughts:
- I find it interesting that they are bringing this up in the middle of 2017. My guess is that stock analysts have been hammering their stock and citing failures of their electrolytic capacitors as one of the reasons.
- I wonder why they didn't specify which products contain electrolytic capacitors. I believe that the M190s and the original M215s contain aluminum electrolytic capacitors and that all later microinverter products do not. But if it is true that they haven't built microinverters with electrolytic capacitors since 2014, why didn't they say so in this presentation?
- If the electrolytic capacitors are not in the top ten failure modes, then what problems ARE in the top 10? Isn't it important to help investors understand that the REAL problems have been understood and addressed in current products?
- The fact that electrolytic capacitors are not in the top ten failure modes for the Enphase microinverters helps to clarify why other manufacturers who don't use those capacitors have such dismal failure rates.
- The scatter plot of capacitance versus time shows results from two manufacturers: Nichicon and UCC. I have discussed Nichicon extensively in this thread, so I am familiar with their products, but I do not even know who UCC is. Does anyone know this company?
- Even if the random failure rate of the aluminum electrolytic capacitors is very low, as they indicated through their original analysis and as they are indicating to their investors in this presentation, the Nichicon aluminum electrolytics cannot be expected to have a lifetime longer than 15 years. Nichicon was very clear about this point in their datasheet for their product. I am quite sure this is why the M190s only have a 15-year warranty. And the switch to metal film capacitors would explain why they can provide a 25-year warranty on the M250s, M215IGs, and later inverters. But that still leaves the original M215s, which apparently share the new packaging and Engage support with the later models, but apparently use a power stage similar to the M190s, including the aluminum electrolytic capacitors. It will be interesting to see what happens after another 10 years in the field with these inverters relative to the M250s and M215IGs. Was Nichicon being overly pessimistic, or do these capacitors really give up the ghost after about 15 years?

In any case, Enphase has confirmed that competitors' marketing about the aluminum electrolytic capacitors is a bit of a red herring. They have also confirmed that there are other things which are driving the higher-than-specified failure rates in their products. The overall M190 population is experiencing approximately 10X as many failures as the datasheet touted and some installations have failure rates that are another 10X worse, or 100X worse than specified. Both the original M215 and the M250 microinverters are holding up well in the field so far and are currently giving MTBF numbers similar to those specified for the M190. (Enphase stopped putting that number on the datasheets after the M190.) But there is one exception: the M215s in GetOffYourGas' system are only giving him an MTBF of about 17 years, or about 20X worse than the original M190 specification of 331 years. We have not collected enough data for any other microinverters to establish a believable MTBF number.
 
RegGuheert said:
I am about to swap in 12 of my new M250-72-2LL-S22 fourth-generation inverters for the 12 third-generation M190-72-240-S12s which are currently attached to the PV modules in the Field Array.
I made the swap on Monday. No more "Grid Gone" events!

OTOH, I just got a new event today from several of the new M250-72-2LL-S22 inverters which I have never seen before: "Skipped Cycles" and "High Skip Rate". I only noticed because there was a considerable drop in production associated with this message. One inverter's production dropped from 168W down to 22W and stayed there for about 10 minutes before it recovered. That's a much bigger dropout than I typically saw associated with "Grid Gone" events from the M190s.

I don't have any idea if this is indicative of a problem or not, but I had hoped that the new inverters would prevent all further dropouts. Does anyone have any experience with "Skipped Cycles"?
 
RegGuheert said:
RegGuheert said:
OTOH, I just got a new event today from several of the new M250-72-2LL-S22 inverters which I have never seen before: "Skipped Cycles" and "High Skip Rate". ...
Does anyone have any experience with "Skipped Cycles"?

Hi RegGuheert,

Yes, I have seen that event log message in the past. It was typically with the older firmware on the fourth generation inverters. Once the firmware is updated you should rarely see this message. If you do see it, the Enphase representative that I spoke with said it can occur during the start-up process of the inverter or at very low power generation situations.

The "skip-rate" refers to dropped power-line communication frames.

I have not seen the message since the first week following the installation of new inverters typically with the Envoy-S gateway.

Respectfully,

Ken Clifton
 
pclifton said:
Yes, I have seen that event log message in the past.
O.K. Thanks! It's good to hear that I'm not alone with this one.
pclifton said:
It was typically with the older firmware on the fourth generation inverters. Once the firmware is updated you should rarely see this message.
It certainly happened with fourth-generation inverters, since I currently have ONLY fourth-generation inverters running in my system right now. Yea! The issue happened with the newest inverters which were manufactured during week 25 of this year. These are running image 520-00044-r1-v01.23.00, which only inverters built since late 2016 are running. Once the Envoy-S was put in place, all older inverters were immediately updated to firmware image 520-00044-r1-v01.22.00. I'm not sure why the older ones are not brought up to 520-00044-r1-v01.23.00, but I suspect it may be because they are not capable of running that firmware.

In any case, the problem occurred in a somewhat-electrically-isolated subarray which only contains these newest inverters running the newest firmware. Interestingly, several of them (but not all 12 of them) experienced this problem at about the same time while none of the older inverters in the other part of the system had any problems.
pclifton said:
If you do see it, the Enphase representative that I spoke with said it can occur during the start-up process of the inverter or at very low power generation situations.
That's not when it happened in my system. The first "Cycles Skipped" event occurred at 11:02 AM, over three hours after the inverters had started up with them producing over 150W.
pclifton said:
The "skip-rate" refers to dropped power-line communication frames.
Sorry, but I just don't buy that explanation. Cycle slipping sounds like what an inverter would do if it is having trouble keeping itself timed with the grid. And, in fact, I saw the power levels drop dramatically at the same time as these messages were reported. I would like to think that the operation of the inverters is not impacted in any way by any communications difficulties which may occur.

As Gene Kranz was famously quoted as saying in Apollo 13:
Gene Kranz in Apollo 13 said:
EECOM, GNC, these guys are talking about bangs and shimmies up there; doesn't sound like instrumentation to me.
pclifton said:
I have not seen the message since the first week following the installation of new inverters typically with the Envoy-S gateway.
Yes, this was during the first week with these new inverters. Whatever the problem is, perhaps it is something that is corrected automatically by some sort of self-calibration that occurs within the inverters. That would explain why it only happens early on. It appears that the Envoy-S pushed out IEEE-compliant grid profiles that were published in 2015, so perhaps it takes the inverters a few days of operation to come into full compliance.

I'll report back in case I see this behavior in the future. Thanks again!
 
RegGuheert said:
pclifton said:
I have not seen the message since the first week following the installation of new inverters typically with the Envoy-S gateway.
Yes, this was during the first week with these new inverters. Whatever the problem is, perhaps it is something that is corrected automatically by some sort of self-calibration that occurs within the inverters. That would explain why it only happens early on. It appears that the Envoy-S pushed out IEEE-compliant grid profiles that were published in 2015, so perhaps it takes the inverters a few days of operation to come into full compliance.

I'll report back in case I see this behavior in the future.
O.K. These new inverters went into service on October 23, 2017. Over one month later, I am still seeing the "Cycles Skipped" messages associated with large power dropouts. It is not always the same inverters showing this issue. It is also not very frequent: the problem occurs only on sunny days.

Here what I saw on Black Friday (November 24, 2017):

First, here is the overall array production at 9:40AM:
Array_Production20171124_940_AM.png


Here is the production for the entire day of the dark inverter seen in the image above:
Microinverter121725058226_Production20171124.png
These dropouts are not overly worrisome, but I must admit that I am very surprised to see them given that I have never seen similar behavior from any previous inverters, including from a couple of late-2016 M215IGs which appear to have the same "jagged" waveforms as these new inverters (which I think indicate that the new versions have moved to all-digital control).
 
RegGuheert said:
including from a couple of late-2016 M215IGs which appear to have the same "jagged" waveforms as these new inverters (which I think indicate that the new versions have moved to all-digital control).
Are you talking about the saw-tooth charts as seen in your screenshot?

If so, that is an artifact of Enphase's dumb decision to move to 15-min interval data from 5-min interval data without updating the user-interface to take that into account.
 
drees said:
RegGuheert said:
including from a couple of late-2016 M215IGs which appear to have the same "jagged" waveforms as these new inverters (which I think indicate that the new versions have moved to all-digital control).
Are you talking about the saw-tooth charts as seen in your screenshot?
Yes, but I'm more specifically talking about this.
drees said:
If so, that is an artifact of Enphase's dumb decision to move to 15-min interval data from 5-min interval data without updating the user-interface to take that into account.
Fortunately all of my inverters are still reporting at 5-minute intervals, including the inverter shown in the waveform above. Both the older and the newest M-series inverters still report results every five minutes, even though their waveforms look different.

I have gone to great lengths to limit Enphase's access to my Envoys in an attempt to prevent them from pushing out this change to my system (while still uploading my information to their servers). We'll see how long I can hold out.
 
Paging Tony Williams...

I looked at your Enlighten site today and noticed a couple of things:

1) Your system stopped reporting on October 20. Did your Envoy die?
2) Enlighten lists 37 inverters even though you have 35 in your array. Have you had 2 M190s die?
 
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