Turbo-AC-coupling - will this work???

[daklein]

While this may be true, my battery can reach full as early as 1 pm. So I still like to run on solar until the sun goes down instead of running the battery for 5 hours. That might be tough to do off grid though. Since I am on grid, I just revert back to letting the Enphase system export the extra to grid again and back up those credits for the few times I do have to buy power.

One of the common dump loads is an electric water heater. I wonder if anyone has tried to use something like a programable high power light dimmer to adjust the current into a water heater to match the extra solar production?? Use all the power the solar panels are producing so the battery state stays flat at your full charge. Use more load in the house, or a cloud goes by, then it lowers the power to the water heater. Obviously, you still need another shut off if the water heater get's too hot, but that can take a very long time.

I use a cheap scr dimmer circuit to dump extra solar into water heater. Wifi relay board adds different combos of resistors, instead of the original manual potentiometer, controlled from raspberry pi listening to main inverters as to available extra power. The original tank thermostat works fine to limit water temperature.

I had maybe similar AC coupling instability issues, with about 40 enphase micros M series up to maybe 7kw total, and 2x SMA SI6048US. Only when running an old PSC compressor A/C unit, with micros putting out plenty of power. No A/C or less AC coupling power or was ok. Replaced the A/C with inverter heat pump, and issues are gone.

 

[z80]

So-o-o-o-o much easier to do all this with Sunny island inverters.... everything just works and is scaleable to the asteroid belt.

 

[zanydroid]

So-o-o-o-o much easier to do all this with Sunny island inverters.... everything just works and is scaleable to the asteroid belt.

What are the 48V UL9540 combinations of that?

 

[Hedges]

I'm finding no UL 9540, inverter has "Certification UL 1741/UL1998" (page 231 of manual)

https://files.sma.de/downloads/SI6048US-DS-en-28.pdf

https://files.sma.de/downloads/SI4548-6048-US-BE-en-21W.pdf

Battery list, approved batteries for the US model start on page 10.

https://files.sma.de/downloads/SI-LiIon-TI-en-48.pdf

Could be they met prior requirements, did not update when UL 9540 appeared in 2016. Because they focused on new HF products.


Sunny Boy Storage does have UL 9540

"Certificates and approvals UL 1741 SA, UL 9540, CSA C22.2 No. 107.1-1, UL 1998, IEEE 1547, PCC Part 15 (Class A & B) CA Rule 21, HECO Rule 14H SRD v1.1"

https://files.sma.de/downloads/SBSXX-US-DS-en-22.pdf

Sunny Boy Smart energy also planned to

"Certificates and approvals (planned) UL 62109-1, UL 1998, UL 1699B Ed. 1, UL9540, IEEE1547, FCC Part 15 (Class A & B), CAN CSA-C22.2, CA Rule 21, HECO Rule 14H, PV Rapid Shutdown System Equipment in accordance with UL1741, NEC 2020, NEC 2023 compliant"

https://files.sma.de/downloads/SBSE-US-DS-en-23.pdf

What are the exceptions to needing UL 9540? Wasn't a UPS exempt, and what distinguishes a UPS?
If Sunny Island serves as battery backup to loads but does not use batteries to backfeed grid at different times from PV production, might it be except?