Need advice on Solar design with regards to interference

[fresnoboy]

FOlks, to carry on the thread a bit. I notice APsystems has a new microinverter, the yc600. It has a metal case, and uses 900 Mhz zigbee mesh for communications and control. Given the use of RF to communicate and no PLC signals, I was wondering if they did a better job with RFI than others?

It also has a max production power of 300W per panel (it connects two panels per inverter), which is a bit better than the 280W from the enphase units.

Anyone have any experience with these?

thx
mike

[fresnoboy]

Fresno - offer still stands - bring up some portable gear and test interference (with the Enphase) to make sure for yourself what others are saying is correct or not about interference. If your in Fresno, its under an hour up Hwy 41.

Thanks for the offer! I may take you up on it if we seriously look at the enphase approach. As it stands now, it would clip at 280W no matter how big my panels are, so I'm going to try and examine a different set of solutions before going down the enphase approach/

Thanks so much for the offer though! I appreciate it!

thx
mike

[tyab]

Fresno - offer still stands - bring up some portable gear and test interference (with the Enphase) to make sure for yourself what others are saying is correct or not about interference. If your in Fresno, its under an hour up Hwy 41.

[fresnoboy]

So my Solar guy got to talk someone at Solaredge, and apparently he told him they discourage installers using their equipment if the homeowner is a ham radio operator. Sounds like they know they have a probelm. Part 15 says equipment cannot cause harmful interference to a licensed radio service, and that includes ham radio allocations.

Why is it people can't fix their stuff to not cause a problem?

thx
mike

[bcroe]

A traditional string inverter will minimize number of noise generators and they could be shielded in a very large metallic enclosure but then you run into all of the rapid shutdown issues (solvable just have to find an installer that knows this area) and have to make sure they get enough airflow in that cabinet

Realize that the metal "cabinet" could be made of hardware cloth, 1/2" squares from woven wire SOLDERED AT EVERY
CROSSING. This will give practically open air ventilation, but RF openings far smaller that 1/10 wavelength for the
frequencies involved. The key is not to allow any long seams/larger openings, because RF is slippery stuff. A door would
need multiple sealing points. Bruce Roe

[tyab]

FYi, the Enphase product line is rapid shutdown compliant - no need to go to the IQ series.Just an observation is that the M250's I have are all metal construction - no plastic like the IQ series - so I would expect decent RF shielding. That said I have not walked by them with an AM radio. I do know for a fact they generate quite a bit of electrical noise enough to interfere with powerline homeplug type of units so I add my vote to make sure the entire Enphase system is on a separate sub-panal and given you are trying so hard to get a clean signal to look at any number of the dual stage filters that can give excellent attenuation on the power line.

A traditional string inverter will minimize number of noise generators and they could be shielded in a very large metallic enclosure but then you run into all of the rapid shutdown issues (solvable just have to find an installer that knows this area) and have to make sure they get enough airflow in that cabinet

From your post I am guessing that this is not a DYI system and you will have professionally installed. Thus you can do require things like "all AC will be in metal conduit and metallic junction boxes - no PVC" so you can Faraday cage as much as possible. And given that you are planning on a larger size system (give the size of the home), I'm sure a number of folks here would be more than happy to allow you to visit their setups so you can test it yourself before signing any contract. Seems like since your needs are not traditional - it is worth your time to test actual systems prior to spending anything.

If your willing to waste a drive to near Yosemite, you are welcome to come by with your RF gear and test to your hearts content as long as you need a 80 Enphase M250 system to see for yourself if they generate noise or not (its ground mount and power is there so you can do whatever). I even have a power outlet that is shielded by a dual stage filter so you can see if that helps or not.

[sdold]

Mike, sorry about the trouble posting, it was nothing you did, the forum sometimes automatically flags posts containing links for moderation.

[ButchDeal]

Are you sure? I saw this on YouTube: https://youtu.be/9SsuscIeqJk

Thx
Mike

That is an early product announcement. They will not be available till late this year or early next. It increases arc fault protection

[fresnoboy]

Are you sure? I saw this on YouTube: https://youtu.be/9SsuscIeqJk

Thx
Mike

[ButchDeal]

Does anyone have information on how the Solaredge S-series optimizers have changed? Do they have the same RFI issues as their predecessors? The solar companies keep chnaging things so its hard to get data. I can visit a solaredge home for testing, but they don't know which optimizers are in there, etc...

thx
mike

SolarEdge doesn't have an S series optimizer. Are you talking about the S series of enphase micro inverters?

https://www.solaredge.com/us/products/power-optimizer#/

https://enphase.com/en-us/products-and-services/microinverters/family

SolarEdge has a new HDWave inverter:

https://www.solaredge.com/us/product...single-phase#/

[fresnoboy]

Does anyone have information on how the Solaredge S-series optimizers have changed? Do they have the same RFI issues as their predecessors? The solar companies keep chnaging things so its hard to get data. I can visit a solaredge home for testing, but they don't know which optimizers are in there, etc...

thx
mike

[Mike90250]

Solar EMI would only be active daytime, nightime, it shuts down, well before the Skip starts up. Daytime, most inverters will trash the broadcast AM band

[bcroe]

The other important part of the sub-panel method of isolation is to use an outlet on that sub panel for the Envoy, so that the 144 KHz signal from the inverters to the envoy is not attenuated, but they are both isolated from the main panel. It worked really well for me using a couple of toroids on the two hot legs between the main panel and sub panel. They were around 1.5 inch diameter, maybe 2", and I'm not sure what the mix was. It was probably 43, I don't know if that's optimum but it's probably what was in my box.

I just measured the effect of my 16 M215s at 1:30 pm in full sun on a 2m radio with the antenna about 20 feet from the array, there was no interference. In ham lingo, the effective sensitivity was about 118 dBm with the inverters on or off, they made less than a dB difference. I've never looked at them on HF though.

Steve

Interference certainly would be way down at 2M frequencies, and the band has typically been FM. HF is
going to be worse with AM and SSB. Bruce Roe

[sdold]

I could go pull the FCC emissions files for these things, but I'm not sure they would tell me anything useful.

You mean the part 15 lab reports? I'm not sure either, but maybe it would be a way to compare different inverters. There might be spectrum analyzer plots, etc. Problem is they might be radiated plots, and I bet most of the trouble is from conducted emissions and I don't think they show spectrum plots of those.

[fresnoboy]

Well, I am not particularly trying to use the Enphase stuff. Its more like I am trying to avoid the Solaredge gear based on the April 2016 QST issue. The M215's are not really an option for me - I need rapid module shutdown for a new install, so it would be the iq6 series from enphase. That case looks all plastic to me which makes me even less confident in going that direction. Does anyone have experience with the ip6's, good or bad?

I can't seem to find an example of a ham with the Tigo optimizers. I think they were bought by SMA, but no ham seems to have said anything about Tigo. Or the new Maxim optimizers for that matter, though people have complained about TV inetrefence in Australia with them, which is a bad sign.

I could go pull the FCC emissions files for these things, but I'm not sure they would tell me anything useful.

thx
mike