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RegGuheert
Posts: 5583
Joined: Mon Mar 19, 2012 4:12 am
Delivery Date: 16 Mar 2012
Leaf Number: 5926
Location: Northern VA

Newest Enphase M-series inverters report jagged production curves

Sat Oct 21, 2017 3:23 am

I have a broad range of Enphase M-series inverters in my system ranging from M190s which were built in 2010 to M250-72s built in 2017. I have taken "measures" to try to prevent Enphase from changing the recording intervals for these inverters from five minutes to 15 minutes. While looking at reported data on Enlighten to see if the interval was still five minutes, I noticed that the newest inverters have jagged production curves while all of the older inverters have smooth curves (except for the M190s, which seem to do something else completely).

Here are a couple of plots:

M215IG manufactured in week 50 of 2016 (Part no. 800-00363-r02) running image 520-00044-r1-v01.23.00:

Image

M215IG manufactured in week 45 of 2015 (Part no. 800-00351-r02) running image 520-00044-r1-v01.22.00:

Image

These inverters sit side-by-side in the array since the newer one was provided by Enphase as a replacement for a failed inverter from the same lot as the older one. Both are being read by the same Envoy-S and both are reporting data every five minutes. The difference seems to be that the newer one appears to report TWO data points at (nearly) each timepoint, thus creating the stairstep look. Note that the Envoy-S recently updated the firmware in ALL the older inverters in the array and none of them were updated to the same level as the newer ones.

Somewhere along the line, Enphase has moved to fully-digital controllers for their inverters and the newer graph looks similar to (but not exactly like) a discrete-amplitude plot. I have no idea if this is related to what I am seeing, or not.

What I don't understand is why Enphase would change to this new format, particularly at a time when they are changing the recording intervals for many customers from five minutes to 15 minutes. IMO, the older, smoother format would not be nearly as objectionable to most people, even if 15-minute intervals were used.

Anyway, it's just a curiosity. It's certainly not critical, but I'm just wondering if others are seeing the same thing in their results. I'll be installing some of the M250-72s next week and expect to see the same jagged curves as I see with the 2016 inverters.
RegGuheert
2011 Leaf SL Demo vehicle
2011 miles at purchase. 10K miles on Apr 14, 2013. 20K miles (55.7Ah) on Aug 7, 2014, 30K miles (52.0Ah) on Dec 30, 2015, 40K miles (49.8Ah) on Feb 8, 2017.
Enphase Inverter Measured MTBF: M190, M215, M250, S280

SolarKings
Posts: 1
Joined: Sun Oct 22, 2017 9:10 am
Delivery Date: 22 Oct 2017

Re: Newest Enphase M-series inverters report jagged production curves

Sun Oct 22, 2017 9:22 am

Neat observation. I have 80 Enphase microinverters spread out over 6 strings. The Enphase microinverters range from M215 non-IG, M215 IG, to M250 models. I have yet to have a single microinverter fail, and even if one does, it's not a big deal, because the other 99% of my 20,000-Watt solar PV system will still be pumping gold!!! That is true decentralized power. Why people keep getting snookered into buying the single point-of-failure optimized-string systems from SolarEdge is beyond me. Enphase is the leader of dentralized power with their 6th-gen IQ microinverter. I've gotten to the point where I just scan the monthly status eMail from Enphase, and if everything reports OK, then fine. I still read my own meter every month, so if my net transfer is in the negatives, I am happy. Good luck!

User avatar
RegGuheert
Posts: 5583
Joined: Mon Mar 19, 2012 4:12 am
Delivery Date: 16 Mar 2012
Leaf Number: 5926
Location: Northern VA

Re: Newest Enphase M-series inverters report jagged production curves

Sun Oct 22, 2017 3:03 pm

SolarKings wrote:I have 80 Enphase microinverters spread out over 6 strings. The Enphase microinverters range from M215 non-IG, M215 IG, to M250 models. I have yet to have a single microinverter fail, and even if one does, it's not a big deal, because the other 99% of my 20,000-Watt solar PV system will still be pumping gold!!!
Welcome to the forum! Can you please share the public link to your system so that I can track its (lack of) failures with the other systems I am tracking on my Enphase Microinverter and Envoy Field MTBF Estimate spreadsheet?
SolarKings wrote:That is true decentralized power. Why people keep getting snookered into buying the single point-of-failure optimized-string systems from SolarEdge is beyond me. Enphase is the leader of dentralized power with their 6th-gen IQ microinverter. I've gotten to the point where I just scan the monthly status eMail from Enphase, and if everything reports OK, then fine. I still read my own meter every month, so if my net transfer is in the negatives, I am happy. Good luck!
I've had more issues since I started with M190s, but I've only had one failure of their fourth-generation inverters (a 2015 M215IG). I'm shooting for many long years with this system going forward!
RegGuheert
2011 Leaf SL Demo vehicle
2011 miles at purchase. 10K miles on Apr 14, 2013. 20K miles (55.7Ah) on Aug 7, 2014, 30K miles (52.0Ah) on Dec 30, 2015, 40K miles (49.8Ah) on Feb 8, 2017.
Enphase Inverter Measured MTBF: M190, M215, M250, S280

User avatar
RegGuheert
Posts: 5583
Joined: Mon Mar 19, 2012 4:12 am
Delivery Date: 16 Mar 2012
Leaf Number: 5926
Location: Northern VA

Re: Newest Enphase M-series inverters report jagged production curves

Mon Oct 23, 2017 2:09 pm

RegGuheert wrote:I'll be installing some of the M250-72s next week and expect to see the same jagged curves as I see with the 2016 inverters.
Confirmed. The M250-72s built during the 25th week of 2017 produce the same jagged curves as the M215IGs which were built in 2016.
RegGuheert
2011 Leaf SL Demo vehicle
2011 miles at purchase. 10K miles on Apr 14, 2013. 20K miles (55.7Ah) on Aug 7, 2014, 30K miles (52.0Ah) on Dec 30, 2015, 40K miles (49.8Ah) on Feb 8, 2017.
Enphase Inverter Measured MTBF: M190, M215, M250, S280

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