Based on the recent reports of M190IG failures by amperedave, I finally broke down and added a section to
my MTBF spreadsheet to track failures of the M190IG microinverters. Please have a look. If you have M190IGs or M19072IGs INSTALLED in your array that I did not list in the spreadsheet, please let me know about them, including when each was installed, if you know it.
Some notes about the spreadsheet and the results:
- We are currently tracking 29 M190IGs. I expect this number to grow with time as more M190s get replaced by M190IGs.
- The M190IGs have by far the lowest overall MTBF of ALL inverter types: only NINE YEARS. This is particularly concerning since they are being provided as replacements for the M190s which suffered from a too-low MTBF. OTOH, the three known failures were all in the same system, which brings up the possibility that those failures may not have been random. Perhaps those failures had a common cause such as lightning.
- The changes to the M190 section of the spreadsheet should improve the accuracy of the overall M190 inverter MTBF calculation, but they make it harder to figure out the MTBF for a given system. If you want to know the MTBF of ALL inverters in your system, you need to add all "Device Years" for both the M190s AND the M190IGs in the system and divide by the total number of "Failures" of all of those same rows.
- Another drawback of this change is that it reduces the accuracy of the MTBF calculation of the Envoys in M190 systems. I have not yet figured out a simple way to improve this.
- I did NOT include M190IGs that are currently used as spares. That includes two M19072IGs that I have and all M190IGs that belong to pclifton.
This might be a good time to update data for all inverter types. Please let me know the status of all rows you are tracking, along with the row numbers for each. TIA.