[RFI] Update: Tesla's Response to Solar Panel RFI

[EDWARDS, EDDIE J]

Tony, 

In POWER line RFI issues with hams on HF bands, the only part of PART 15 that applies is the harmful interference clause.  This has worked effectively for decades.  So I am assuming, and I could be wrong, this should also apply to solar POWER since it is also a POWER issue.  

I just noticed today that Part 15 has been changed recently.  "Operating Requirements" used to be in 15.25 per ARRL RFI Book (1st Edition), but they are now in 15.5 which is the crux of harmful interference and rights of the neighbor versus the ham.  

Clearly radio services trumps neighbor's rights in 15.5: "Persons operating intentional or unintentional radiators SHALL NOT be deemed to have any vested or recognizable right to continued use of any given frequency by virtue of prior registration or certification of equipment...".

https://www.ecfr.gov/cgi-bin/text-idx?SID=00d6fe71368c89a2357a3ab7e96f1055&mc=true&tpl=/ecfrbrowse/Title47/47cfr15_main_02.tpl  

Here are the portions of Part 15 that I believe should apply to your situation, but I could be wrong since they've modified Part 15 and I only skimmed the changes today: 

Under Part 15 Definitions:  
Section 15.3 (m) Harmful interference. Any emission, radiation or induction that endangers the functioning of a radio navigation service or of other safety services or seriously degrades, obstructs or repeatedly interrupts a radiocommunications service operating in accordance with this chapter. 

15.13   Incidental radiators.  
Manufacturers of these devices shall employ good engineering practices to minimize the risk of harmful interference.

15.15   General technical requirements.  
(a) An intentional or unintentional radiator shall be constructed in accordance with good engineering design and manufacturing practice. Emanations from the device shall be suppressed as much as practicable, but in no case shall the emanations exceed the levels specified in these rules. 
(b)...skip...  
(c) Parties responsible for equipment compliance should note that the limits specified in this part will not prevent harmful interference under all circumstances. Since the operators of part 15 devices are required to cease operation should harmful interference occur to authorized users of the radio frequency spectrum, the parties responsible for equipment compliance are encouraged to employ the minimum field strength necessary for communications, to provide greater attenuation of unwanted emissions than required by these regulations, and to advise the user as to how to resolve harmful interference problems (for example, see §15.105(b)). 

15.5   General conditions of operation.  
(a) Persons operating intentional or unintentional radiators shall not be deemed to have any vested or recognizable right to continued use of any given frequency by virtue of prior registration or certification of equipment, or, for power line carrier systems, on the basis of prior notification of use pursuant to §90.35(g) of this chapter. 
(b) Operation of an intentional, unintentional, or incidental radiator is subject to the conditions that no harmful interference is caused and that interference must be accepted that may be caused by the operation of an authorized radio station, by another intentional or unintentional radiator, by industrial, scientific and medical (ISM) equipment, or by an incidental radiator. 
(c) The operator of a radio frequency device shall be required to cease operating the device upon notification by a Commission representative that the device is causing harmful interference. Operation shall not resume until the condition causing the harmful interference has been corrected. 

The last paragraph (c) I remember was basically used by the FCC to force Reliant Energy to replace a $100,000 transformer that was causing RFI to only one ham operator.  This after Reliant lawyers tried to tell FCC that there were no FCC rules in Part 15 or otherwise that applied to the problem.  

Harmful interference to one ham (a DXer) is going to be different to another ham (80-meter rag-chewer), so it depends on what the FCC considers harmful interference if they get involved.  With power-line noise, once the FCC is involved, the utility usually has around 60 days to respond with a plan to fix the RFI, and probably another 30-60 days to resolve the issue.  But will they hold the owner of the solar panels to the same high expectations?  Or will they hold the vendor or his installer responsible for the fix.  This is the gray area we are in today.  

My apologies if I missed a critical portion of Part 15 that may apply here.  Just found the changes this morning.  Please respond with any corrections.  

73, de ed -K0iL
Omaha, NE

-----Original Message-----
From: RFI <rfi-bounces at contesting.com> On Behalf Of Tony
Sent: Tuesday, December 17, 2019 8:48 PM
To: Tony Brock-Fisher <barockteer at aol.com>; Rfi List <rfi at contesting.com>; Cianciolo, Paul, W1VLF <pcianciolo at arrl.org>
Subject: Re: [RFI] Update: Tesla's Response to Solar Panel RFI

READ THIS FIRST! This is NOT an OPPD email.Be very cautious of any links or  attachments unless you recognize this sender - rfi-bounces at contesting.com and are expecting this email.Please click the "Report it" button if you think this email is malicious.

Ed:

My case with SolarEgdge is the one that has not been resolved so I'd like to ask you a few questions and respond to the confusion regarding the RFI from my neighbors system continuing after it was disconnected.

I was at the site each time the crew attempted to fix the RFI issue and they NEVER disconnected all of the solar panels from the system at one time. They instead worked on one section at a time so the majority of panels and optimizers remained in service, hence the noise.

The SolarEdge tech at the site said that the system continues to generate noise as long as the optimizers are connected to the solar panels. I have the emails from SolarEdge confirming this.

The only effect I noticed during the process was a fluctuation in the noise when they handled the panels and cabling.

I've asked many times if they would disconnect / disassemble the entire system as a process of elimination in order to isolate the noise, but they said it wasn't necessary.

As far as the source of the noise, I was present the day they installed the system in 2016 which is when the noise began. At S-9 plus, the source was blatantly obvious then as it is now. Seeing the noise fluctuate as the crew handled the panels also confirms the source.

Please correct me if I'm wrong, but after reading your post, there doesn't seem to be anything in regulations that would force SolarEge through to fix the problem as long as their devices meet FCC emissions standards.

So what recourse do amateurs have in a scenario like mine where the noise renders HF unusable? I can't sue them on a retirees pension.

Thanks for your time.

Tony -K2MO


On 12/17/2019 1:55 PM, Hare, Ed W1RFI wrote:
> Let me see if I can put this into perspective.
>
> First, there are a number of factors here that are not usually made part of the discussions about solar arrays that are being installed.  The first is the applicable FCC rules.  These are regulated by Part 15 of the FCC's rules.  Under the rules, they are "unintentional emitters,"   devices that intentionally internally generate RF signals (> 9kHz), but that do not intentionally radiate them.  As unintentional emitters, the manufacturer is subject to the following regulations:
>
> 1, They must meet radiated emissions limits.  These apply ONLY above 30 MHz. They are set at a level such that from a "legal" device next door, one might see about S7 noise on 6 or 2 meters.
> 2. There are NO radiation limits below 30 MHz.
> 3. Below 30 MHz, the FCC controls interference by limiting the amount of noise that can be placed on the AC mains through limits on conducted emissions.  This includes ONLY the ac mains and there are no limits to the conducted noise that may be present on the wires leading from the solar-system electronics to the panels.
> 4. The system must use "good engineering practice,' whatever that means. This generally means that if they make any attempt at filtering, such as a few strategically located capacitors, they would probably be considered as having met this requirement. I have never seen FCC take any action related to "good engineering practice.
>
> Incidental emitters are not subject to certification by the FCC. Older designs were brought forward under the "Verification" authorization in the old rules, and today, more likely through a manufacturer's declaration of conformity. Both are, in essence, self-tested and self-policed.
>
> This is a key here, because from all indications, the devices meet the conducted emissions limits below 30 MHz,  so any radiation from the system is not directly covered by FCC rules.
>
> We don't like the current limits, but they have been in place for decades, and it is highly unlikely that FCC will ever seek to change them.   But in planning what to do, it is critical that Amateurs fully understand just what does and does not apply to the manufacturers.  Any claims that these devices are in and of themselves illegal appears to be incorrect, because from all indications, they meet the requirements for radiated and conducted emissions.
>
> The rules then require that the operator of the device, ie the neighbor and possibly the solar provider, use them in a way that does not cause harmful interference.  First, harmful interference is defined as the repeated degradation of a non-emergency service, or any degradation of emergency communications.   It is often in the eye of the beholder.  FCC, for example, has typically deemed that noise that is below the median values of man-made noise described in ITU-R P372.12 is not harmful interference; it is just noise. This is typically about S6 on 40 meters, so any "marginal" cases are apt to not pass through the FCC process much past advisory letters.   Even more key, if the devices meet the radiated and ac-mains conducted limits, there is no enforcement even possible against the manufacturer.  If there is harmful interference, as defined by the rules, then the operator of the device must correct it, as ordered by the FCC. So, in trying to address this, the manufacturer would be well within its rights to claim that it meets the rules and, from there, any action it took would be voluntary.  The operator is still responsible.
>
> Tesla and the FCC are NOT saying that systems can be put in whether there is interference or not; they are saying that the POTENTIAL for interference is not a reason for people to not be permitted to install solar systems.  This is correct.  There has always been a potential for Amateurs to cause interference to over-the-air broadcast, even from transmitters that meet the rules, but that potential is not enough to preclude Amateurs from installing stations in residential environments.  Tesla and FCC are saying the same thing.
>
> Solar Edge is essentially the manufacturer of these products. So far, they have truly stepped up to the plate in a way that I believe should be appreciated, not criticized.  Yes, there systems are among the noisy ones, but they have been working with Amateurs, installing new panels, optimizers and filters, and virtually all of the cases that ARRL has heard about have been resolved correctly.  Paul Cianciolo, W1VLF, has been involved with them for almost a year now, and they are continuing to resolve problems on a case-by-case basis.  Now, the scheduling for doing that can sometimes be several weeks out, but they are not avoiding all responsibility and are, to the contrary, stepping up in a way that I think we wish all manufacturers would.
>
> We know of one case that remains unresolved.  In this case, we are getting different stories from the amateur and from Solar Edge. Now, so far, the stories we get from both sides have been in very close agreement, but in this case, Solar Edge has visited the site at least three times, replaced panels and optimizers, as we have seen done in other cases that were 100% successful, including at W1VLF's own home.  According to the Amateur, even when the system was disconnected, there was still noise, and this is dramatically different from what Paul experienced when they did these fixes to his own home installation.  Anything is possible, including the possibility that something was left energized to the possibility that there is some other noise source other than the one being worked on.  ARRL is continuing to work with Solar Edge and this complainant, because we want to get to the bottom of this.
>
> We do NOT want to lose the cooperation we have with Solar Edge.  Every case that becomes an FCC matter, though, runs the likelihood that company lawyers, not engineers, will be asked to solve the problem. This case is one in point, because I can clearly see the hand of the legal department in writing that letter. It is correct; they have tried really hard to fix this, there is question and disagreement about the source of the interference and yes, the POTENTIAL for interference that exists with nearly any device is not a legal reason to stop homeowners from installing systems.   ARRL is doing all it can to try to keep this on track, and will, as needed, be prepared to some field work to try to get to the bottom of differences of opinion.  The more "official" this gets, the more the lawyers will be involved and we well may be one legal decision away from lawyers telling engineers to stop all the cooperation, or at least to run each and every step through the Legal Department. I have the results of that, and it ain't pretty.  I want to keep this on the technical level, and we will all be better off if we do.
>
> Ed Hare, W1RFI
> ARRL Lab