I would not expect some foam to stop > 60db of rfi. It would not surprise
me if > 60 db would not be stopped with better solutions like cores etc.
They installed some "we cannot explain what they are" filters on the system
near me about two years ago and it made about a 3-6 db improvement.
About 50 db to go...not seen or heard from anyone since. No response to my
emails or phone calls.
Perhaps I need a bigger hammer to get their attention. (As tempting as it
is I am avoiding the use of a real hammer). Maybe I could contract out to
the little old lady that busted up a Comcast office with a hammer. :-)
Part 15 works in both directions. One could wounder how much rf at what feq
one would have to generate to get their attention?
Imagine the motivation solar edge would have if their arrays near hams
started ramdomly going off line.
Beyond frustrated. I haven't been on hf for several years because of the
RFI. Even vhf is difficult.
At least dmr gets me some air time.
On Thu, Oct 11, 2018, 11:04 AM Hare, Ed W1RFI <w1rfi@arrl.org> wrote:
> I doubt that the foam will do all that much. First, as you point out, the
> noise is probaby being radiated by the wires, not the box. Second,
> RF-absorber foam is usually not very effective at HF. It may gain a few dB
> above 30 MHz to allow a device to pass radiated emissions tests, but on HF,
> it would generally be pretty useless.
>
> If the engineers are not aware of good EMC practices, this may explain
> some of the reasons that some of these installations do not seem to have
> RFI cured when the engineers or installers install "cures."
>
> Mike Gruber, can you pass along to the Solar Edge engineers you work with
> some feedback on the effectiveness or lack therof of some of the things
> they are trying to fix?
>
> -----Original Message-----
> From: RFI [mailto:rfi-bounces@contesting.com] On Behalf Of Tony
> Sent: Saturday, October 06, 2018 3:59 PM
> To: rfi@contesting.com; Gruber, Mike W1MG; Tony Brock-Fisher
> Subject: [RFI] Solar Panel RFI in Kings Park - Update October 4th 2018
>
> All:
>
> The RF Engineers from Solar Edger came out to my home this week to assess
> the noise emanating from my neighbors solar panel system.
>
> They plugged into my antennas to view the spectral noise on my receiver
> which they then compared to the spectral noise that appeared on their
> portable setup near the solar panels. They determined the noise to be one
> and the same.
>
> The next course of action is to improve the ground system and install RF
> absorbing foam to each optimizer. I also convinced them to replace the
> snap-on ferrites located at each optimizer, with larger ones so they can
> loop several turns of cable around each core.
>
> They originally said they would just go with the RF foam which is
> puzzling: I don't understand how encasing a noisy device with this stuff
> could suppress RFI when the device is attached to long runs of cable that
> act like antennas. Can anyone explain how that would work?
>
> Tony -K2MO
>
>
>
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