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[RFI] Solar Power: Where we stand. Was Re: Noise from Generac Solar cont

To: David Eckhardt <davearea51a@gmail.com>
Subject: [RFI] Solar Power: Where we stand. Was Re: Noise from Generac Solar controllers?
From: "Hare, Ed, W1RFI" <w1rfi@arrl.org>
Date: Fri, 17 Dec 2021 01:53:05 +0000
List-post: <mailto:rfi@contesting.com>
Thanks for clarifying, Dave.  When I saw some of the incorrect information 
taking on a life of its own, I needed to jump in, although it is just luck that 
I managed to read this deep into the thread.  The ARRL Lab is running 
shorthanded right now and I don't have as much time for these lists as I might 
like.

First, the regulations.  To summarize:

o    Home solar systems are digital devices, classified as unintentional 
emitters under Part 15.
o    Home solar systems do not meet the criteria to be categorized as devices 
that are exempt from the emissions limits.
o    Large "solar farms" are also digital devices, but because they are power 
generation not connected to residences, they COULD be classified as exempt from 
specific limits.  That has never been tested, but we do need to keep that in 
mind.
o    Under the rules, these solar systems are authorized by a Suppliers 
Declaration of Conformity, or, optionally, certification.
o    An SDOC is essentially a self-validation, where the manufacturer issues a 
statement that it complies with the rules.  For the most part, from all 
indications, these devices do.
o    Under the Class B rules, devices that are not exempt must meet conducted 
emissions limits onto the AC mains below 30 MHz. They must meet radiated 
emissions limits above 30 MHz.  The conducted noise onto the wiring to the 
panels is not regulated by Part 15.  From all we can tell, the solar systems 
being marketed do meet the letter of the emissions limits rules.
o    Manufacturers are responsible for having designs that meet the emissions 
limits and for marketing them appropriately.  For example, a solar system could 
be designed for installation on businesses in a way that met the higher 
commercial limits, but it must be marketed only for use in commercial 
environments.
o   These are the ONLY EMC requirements that the manufacturer must meet.
o   The rules also stipulate that otherwise-legal devices must not cause 
harmful interference to licensed radio users such as amateur radio, CB, 
broadcast reception etc.  This is a requirement that is placed on the OPERATOR 
of the solar system, ie a neighbor, the ham him/herself or, in some cases, the 
utility or third party.  So, when a manufacturer steps in to address harmful 
interference, it is doing more than the rules require.  This is important to 
know.

Those who observe that the limits are high are correct.  If a "barely legal" 
Part 15 device of any sort were operated in the home of a neighbor 100 feet 
away, for example, noise around S7 would be typical, plus or minus.  Almost all 
of the cases that ARRL takes to the FCC are moved forward on the basis of 
harmful interference, making measurements of conducted and radiated noise 
irrelevant.  The FCC has taken that issue seriously enough to authorize 
considerable staff time to writing a good number of advisory letter, so it does 
care, but needs help to direct its resources efficiently.

Now, part of the crux of the issue is "harmful interference." Not every noise 
is harmful interference to the FCC.  The definition is vague, and we want it to 
stay that way.  If we were to ask the FCC to draw a firm line in the sand and 
set a level for "harmful interference," it is almost certain that the FCC would 
draw a line we don't like.  If, for example, it drew the line at the current 
conducted and radiated emissions levels, we would be looking at some pretty 
serious noise.

There is, of course, ambient noise everywhere.  The median level of man-made 
noise on HF ranges around S6 on the lower bands, S4 on the higher bands.  
Harmful interference complaints below this level are usually not well received 
by the FCC, under the principle that half of the locations in residential 
environments have this noise level half of the time on half of the frequencies, 
so even when noise levels changes, it considers the noise to be typical of 
noise everywhere.

This doesn't mean that hams are always stuck. To the contrary, all three of the 
solar companies I am working with is looking to reduce the noise from their 
systems as low as can be done, although below the levels I described, this is 
still a work in progress.

So the bottom line is that hams can relief, effectively for strong noise 
sources, and, in the long run, hopefully at lower noise levels as well, with 
the industry going over and above, or under and below, what the regulations or 
FCC would mandate if pressed.

This is much like the BPL days, when parts of the industry resisted notching 
the ham bands, but other parts implemented those notches, to good effect. That 
got picked up internationally and made part of the ITU requirements for BPL. 
So, in the US, we "lost" the regulatory battle, but behind the scenes, worked 
with the "good guys" who helped bring the effective EMC solutions to the table 
internationally.

We are seeing the same sort of thing with the solar companies that are involved 
in interference complaints doing more than the rules require and looking for 
ways to do better yet.

As I have learned in my industry standards work, this is the real way things 
get done, because all the rules in the world are not enough, but cooperation 
and reasonable expectations and a bit of patience are. I was patient for 14 
years with BPL and, in the long run, not only did it solve the problem, but 
that patient and technically honest approach built the reputation of amateur 
radio to the point where our presence in industry circles is both welcome and 
wanted, with amateurs elected to leadership positions in major industry 
organizations and committees. (For example, ARRL is a member of the C63 EMC 
Committee, chairing subcommittees, writing standards that are incorporated by 
the FCC into its rules.  I also serve on the IEEE  EMC Society as its Vice 
President for Standards. All of this was possible because we took a steady and 
technically correct approach to helping to solve problems.

Ed, W1RFI



________________________________
From: David Eckhardt <davearea51a@gmail.com>
Sent: Thursday, December 16, 2021 6:19 PM
To: Hare, Ed, W1RFI <w1rfi@arrl.org>
Cc: Ken Bandy, KJ9B <ken.kj9b@gmail.com>; Rfi List <rfi@contesting.com>
Subject: Re: [RFI] Noise from Generac Solar controllers?

Yes, I may have jumped to conclusions too fast based on what I wanted to see.  
Apologies to everyone on the RFI list.  I've been out of it in retirement for 
some 11 years and am not as sharp as I once was.

However, I do have a LOT of problems with the whole solar power industry 
ignoring what they know to be true.  The statement from SolarEdge confirms that 
wrt "HAMS".  Until they are called on the carpet, nothing will be done - 
remember BPL.  In that respect it seems that ARRL has assumed the role of the 
old FCC I once knew when first licensed in 1960.  Sad, but ARRL is highly 
capable.  Just that my patience is wearing thin wrt the solar power industry 
and RFI.  Sure, it costs money and better and more rigorous instructions for 
instals.  But, come on......!  We have enough RFI coming in from China with no 
attention (or ignoring) EMC/RFI requirements.

This is all from me for this thread.

Dave - WØLEV

On Thu, Dec 16, 2021 at 10:24 PM Hare, Ed, W1RFI 
<w1rfi@arrl.org<mailto:w1rfi@arrl.org>> wrote:

You are not “well aware” if you were looking in the FCC certification database 
for reports on digital-devices unintentional emitters.  They are not required 
to file anything into the certification database.

I do not find the words “Class C” anywhere in Part 15.  There are Class A 
industrial devices and limits and Class B residential devices and limits.  You 
may be talking about the section in Part 15 Part C, intentional emitters. Those 
are certificated, but Part C devices are not industrial devices; that is the 
description of intentional emitters.







From: David Eckhardt <davearea51a@gmail.com<mailto:davearea51a@gmail.com>>
Sent: Thursday, December 16, 2021 5:17 PM
To: Hare, Ed, W1RFI <w1rfi@arrl.org<mailto:w1rfi@arrl.org>>
Cc: Ken Bandy, KJ9B <ken.kj9b@gmail.com<mailto:ken.kj9b@gmail.com>>; Rfi List 
<rfi@contesting.com<mailto:rfi@contesting.com>>
Subject: Re: [RFI] Noise from Generac Solar controllers?



Yes, ED, I'm well aware of all that.  In my looking at all the reports filed 
with FCC, none addressed the complete system, only the intentional radiators 
(Zigibee, BlueTooth, or whatever).  Yes, as a Class B filing, no report is 
necessary.  They must have modified those wireless modules, likely the antenna 
or digital format, to require testing and approval.   No one in their right 
mind as a user of widely available wireless modules wants to own the FCC 
approval for those.  Let the suppliers own the regulatory requirements.  If 
they are modified in any way, antenna or digital protocol, then, yes, the user 
must certify the module.



And why do the filed reports - all of them - claim compliance to Class C, 
industrial?



Dave - WØLEV



On Thu, Dec 16, 2021 at 10:07 PM Hare, Ed, W1RFI 
<w1rfi@arrl.org<mailto:w1rfi@arrl.org>> wrote:

David,

Solar systems are digital devices that are classified as unintentional 
emitters. If they are marketed into residential environments, they must meet 
Part 15 B emissions limits. The only unintentional emitters that require 
certification that would create an entry in the database you looked at are 
scanning receivers, radar detectors and access BPL devices.  Although they CAN 
certify if there is no US resident willing to take responsibility under a 
Suppliers Declaration of Conformity, the vast majority of unintentional 
emitters are not certificated, so there will be no information on the FCC page 
containing test data.  An SDoC is essentially self-policed.  The rules do not 
require that test data on devices authorized under an SDoC be provided to the 
FCC.

If they are using a certificated WiFi or Zigbee device that is used intact, its 
certification would suffice, so there would not be a need for a separate entry 
in the database, no more than you would need to certificate your station if you 
bought and installed a certificated Bluetooth microphone in it.

Ed, W1RFI





-----Original Message-----
From: RFI 
<rfi-bounces+w1rfi=arrl.org@contesting.com<mailto:arrl.org@contesting.com>> On 
Behalf Of David Eckhardt
Sent: Thursday, December 16, 2021 4:55 PM
To: Ken Bandy, KJ9B <ken.kj9b@gmail.com<mailto:ken.kj9b@gmail.com>>
Cc: Rfi List <rfi@contesting.com<mailto:rfi@contesting.com>>
Subject: Re: [RFI] Noise from Generac Solar controllers?

IN further poking around on the FCC OET site under Generac, I can't find a 
single report filed on anything except wireless hardware.  I could not locate 
any complete systems which would include the panels, optimizers, other 
electronic switching devices, and simulated house wiring.  There is no evidence 
in the reports of any test results being filed with the FCC for the entire 
system.  All the "Max Freq '' frequencies listed on the response pages for a 
general search on Generac on the FCC OET pages reflect only above roughly 700 
MHz.  This tells me they are only filing for the intentional radiator, that 
being ZigBee or BlueTooth or some other protocol.  No complete *system test* is 
filed with FCC.  So, how can they claim compliance to even Part 15, Subpart C 
(Intentional radiator), Class C (industrial).  BTW:  Class C systems *do* 
require filing a test report with FCC.  There is none.

Dave - WØLEV

On Thu, Dec 16, 2021 at 5:06 AM Ken Bandy, KJ9B 
<ken.kj9b@gmail.com<mailto:ken.kj9b@gmail.com>> wrote:

> Hi all.  I am contemplating having a “PowerHome Solar” power system
> installed at my house, and am a little concerned about possible RF
> noise generation from the system.  This system uses a Generac
> controller.  Does anyone have any experience with a system using a
> Generac controller?  I know early inverters were often RF noisy, but
> I’m hoping that the later models have addressed noise generation.
>
> Any input is appreciated.
>
> 73,
> Ken, KJ9B
>
>
> _______________________________________________
> RFI mailing list
> RFI@contesting.com<mailto:RFI@contesting.com>
> http://lists.contesting.com/mailman/listinfo/rfi
>


--
*Dave - WØLEV*
*Just Let Darwin Work*
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Dave - WØLEV

Just Let Darwin Work




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Dave - WØLEV
Just Let Darwin Work

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