pclifton on December 14, 2015 wrote: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 wrote: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!