The issue has to do with the Maximum Input DC Voltage. That is the second specification listed in the comparison table I created for the various Enphase microinverters. As you can see, the M190s are rated for 56 V DC while most of the others, including the new S230 and S280, are rated for 48 V. The original M215 (non-IG) is the oddball, at only 45 V.pclifton wrote:Perhaps you can educate me about this:I have 31 Sharp 235W mono panels as well as some 375 SW. Twenty-four of the Sharps are connected to the M190s. As you know, two of my four replacements have been the M190IG(s). I have been considering replacing all of the M190s with the new S230(s) when they are out at some point. I installed my systems and as the years go by I will reach a point where I can't keep swapping out inverters. I ran into that last year while I was blind.Since the field array contains 72-cell PV modules (in a climate which gets cold enough to break the new-style inverters), I will need to keep the original-style inverters out there as long as possible.
Anyway, your statement gives me some concerns about that plan -- if I understand you correctly...
The issue with 72-cell panels is that their open-circuit voltage exceeds 48 V at temperatures below about -5F (IIRC). If that happens during the life of the non-M190 microinverters, catastrophic failure could occur.
Sharp 235-W mono panels are exactly what I have on my roof and they are no problem, since they are 60-cell panels. But I have 72-cell panels connected to 12 microinverters in the field array.
I guess I'm wondering why you would want to upgrade. As you can see from my data above, there is NO difference in production between the different inverters when coupled with the Sharp 235-W modules. There will be VERY slight differences in the wintertime, but that will be even less of an issue in your warmer climate. Are you just tired of replacing the M190s?
FWIW, I have 9 M250s for sale that I recently acquired. They're used, so they have no warranty, but I'll give you a good deal if you are interested.
One final note: It seems the S230 will NOT connect to your existing Envoys. If you purchase them, you will need to upgrade the Envoy(s) to which you intend to connect them.