[RFI] SolarEdge Solar Panel RFI Update

[Gary Johnson]

Here is an update on my particular SolarEdge noise complaint. System with panel optimizers was installed in late May. The specific RFI that it produces is only at 200 kHz intervals due to control telemetry. The company has been responsive. The young engineer I've been working with is Tom "TJ" Simpson. He said that anyone, anywhere, that has noise issues is welcome to contact him. He lives in the SF Bay area.

TJ Simpson   
Senior Field Service Engineer
Office: 510.498.3200  
Tom.Simpson at solaredge.com

Last week, TJ and two helpers rerouted cabling to eliminate a big loop. Then they installed type 31 big clamp-ons, with a few turns, on each side of every optimizer. We had a lively discussion about chokes. Using type 31 was an experiment (I told him I'm open to that). Their preferred mix is 75 and he says those have been very effective. Interestingly, he said that in lab testing their telemetry would fail with certain chokes... Particularly chokes that had what we know to be sufficient choking impedance to do a proper job of reducing commmon-mode currents. Makes no sense to me. 

I did confirmed that, with system off, it makes no noise at all that I can discern (my dipole is 35 ft away from the nearest panel). When reactivated post-mitigation, 200 kHz spurs were at least as strong as before, so additional work will be performed.

They will be back in 10 weeks to install new optimzers that are spread-spectrum. I have direct experience with various SS systems involving ground-penetrating radar and certain military equipment. Depending upon the occupied bandwidth and the spreading technique this could be either very effective or even more annoying than just having a 2 kHz-wide spike every 200 kHz. We’ll see. Lucky for me, I have a new remote station going online and my RFI-compromised home station will be reserved for experimentation.

-Gary NA6O