Hi

Do you folks have any comments on these new Micro Inverters? Specically the
Enphase M215. I understand there is a new one Enphase M215 IG I believe that
addresses the interference experience by hams on VHF band. These are the
Micro Inverters two suppliers tole me to use that qualify for the Ontario
Microfit program. I reading reviews on Amazon that they are very
interfering. Is there a way of grounding them or a equal alternative model
that doesn't interfere with ham bands during peak sunlight hours? I need to
put 50 of these on my roof under each panel. Any and all comments are
greatly appreciated as always. Thanks Gents,,,

73s

Tom

On Tue, 28 Jul 2015 07:05:54 -0400, "Tom" wrote:

Do you folks have any comments on these new Micro Inverters? Specically the
Enphase M215. I understand there is a new one Enphase M215 IG I believe that
addresses the interference experience by hams on VHF band. These are the
Micro Inverters two suppliers tole me to use that qualify for the Ontario
Microfit program. I reading reviews on Amazon that they are very
interfering. Is there a way of grounding them or a equal alternative model
that doesn't interfere with ham bands during peak sunlight hours? I need to
put 50 of these on my roof under each panel. Any and all comments are
greatly appreciated as always. Thanks Gents,,,

I help maintain a few grid tied solar systems. Most use Enphase micro
inverters. The latest uses M215 IG inverters. Previous models were
totally floating and had no grounding points or fault protection. The
IG means "integrated ground" and also has a built in ground fault
protector. The grounding change probably has nothing to do with
EMI/RFI. There are also Chinese clones of these inverters, which
ended up at one of these systems thanks to a fly-by-night solar
contractor.

My guess(tm) is you're dealing with conducted EMI/RFI, not radiated.
Therefore, clamp on ferrite beads and blocks should work.
http://www.solar-electric.com/installation-parts-and-equipment/electrical-devices-transfer-switches-noise-filters/nosufefi.html
When I complained on behalf of one customer that the inverters were
trashing OTA TV reception, they installed the ferrite beads for free.
I don't think Enphase supplied the ferrites. It's mentioned in their
troubleshooting guide, but nowhere else:
http://www2.enphase.com/global/files/Enphase_Troubleshooting_Guide.pdf
See Pg 22. Note that the filters go as close to the source of the
noise (i.e. the M215 IG micro inverters) as possible.

I think the M215 IG uses the same 144KHz communications frequency and
Zigbee protocol as most everyone else. The problem is that it uses
the same power lines that are conducting the switching noise for
communications. If your added ferrite beads clobber this signal, the
Envoy controller box is going to complain that it can't communicate
with the panels. So, be careful when you add a ferrite block as too
big a block, wrong material, too many beads, or too many turns, is
going to cause problems. I would aim for a 500 KHz low-pass corner
frequency.

As for grounding, the evolving NEC Article 690.35 for the US requires
that literally everything on the roof be well grounded. Since I
believe that the noise will be conducted rather than radiated,
additional grounding isn't going to do anything useful. In my never
humble opinion, filtering is your only option.

Good luck.

Light reading:
http://www.homepower.com/solar-electricity






--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Thank you for the information.

That is it in a nutshell. I am waiting for approval for the program, If
approved then I can go forward to begin purchasing the system and start
building it.

Thanks again for this info,

73s







"Jeff Liebermann" wrote in message
...
On Tue, 28 Jul 2015 07:05:54 -0400, "Tom" wrote:

Do you folks have any comments on these new Micro Inverters? Specically
the
Enphase M215. I understand there is a new one Enphase M215 IG I believe
that
addresses the interference experience by hams on VHF band. These are the
Micro Inverters two suppliers tole me to use that qualify for the Ontario
Microfit program. I reading reviews on Amazon that they are very
interfering. Is there a way of grounding them or a equal alternative model
that doesn't interfere with ham bands during peak sunlight hours? I need
to
put 50 of these on my roof under each panel. Any and all comments are
greatly appreciated as always. Thanks Gents,,,

I help maintain a few grid tied solar systems. Most use Enphase micro
inverters. The latest uses M215 IG inverters. Previous models were
totally floating and had no grounding points or fault protection. The
IG means "integrated ground" and also has a built in ground fault
protector. The grounding change probably has nothing to do with
EMI/RFI. There are also Chinese clones of these inverters, which
ended up at one of these systems thanks to a fly-by-night solar
contractor.

My guess(tm) is you're dealing with conducted EMI/RFI, not radiated.
Therefore, clamp on ferrite beads and blocks should work.
http://www.solar-electric.com/installation-parts-and-equipment/electrical-devices-transfer-switches-noise-filters/nosufefi.html
When I complained on behalf of one customer that the inverters were
trashing OTA TV reception, they installed the ferrite beads for free.
I don't think Enphase supplied the ferrites. It's mentioned in their
troubleshooting guide, but nowhere else:
http://www2.enphase.com/global/files/Enphase_Troubleshooting_Guide.pdf
See Pg 22. Note that the filters go as close to the source of the
noise (i.e. the M215 IG micro inverters) as possible.

I think the M215 IG uses the same 144KHz communications frequency and
Zigbee protocol as most everyone else. The problem is that it uses
the same power lines that are conducting the switching noise for
communications. If your added ferrite beads clobber this signal, the
Envoy controller box is going to complain that it can't communicate
with the panels. So, be careful when you add a ferrite block as too
big a block, wrong material, too many beads, or too many turns, is
going to cause problems. I would aim for a 500 KHz low-pass corner
frequency.

As for grounding, the evolving NEC Article 690.35 for the US requires
that literally everything on the roof be well grounded. Since I
believe that the noise will be conducted rather than radiated,
additional grounding isn't going to do anything useful. In my never
humble opinion, filtering is your only option.

Good luck.

Light reading:
http://www.homepower.com/solar-electricity






--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Sun, 2 Aug 2015 07:15:26 -0400, "Tom" wrote:

That is it in a nutshell. I am waiting for approval for the program, If
approved then I can go forward to begin purchasing the system and start
building it.

One more potential problem. Enphase has an online monitoring system
at:
https://enlighten.enphaseenergy.com
https://enlighten.enphaseenergy.com/public_systems
I suggest that you eventually sign up as a system owner. You can
download the data and create your own graphs such as:
http://802.11junk.com/jeffl/solar/380732/total-energy-21040613-20150213.jpg

Incidentally, you can query the Envoy controller directly either via a
web interface or using a graphing program (MRTG):
http://blog.tinle.org/?p=111
http://pvoutput.org
http://pvoutput.org/outputs.jsp
None of the system owners I deal with want me to do this, so I haven't
bothered to try it.

Now that I'm thinking about it, you might run into another problem.
The People's Republic of Santa Cruz (county) uses the NFPA NEC code
which now demands 2ft of clearance between the roof peak and the solar
panels. This clear area is for ventilating the roof should the house
catch fire. I have some issues with this requirement because it
significantly reduces the available roof area for panels for no
benefit because the other side of a typical hip roof is usually clear
of solar panels. You might want to check whether this is a
requirement in your area. I have some docs on the topic if becomes a
problem.

Good luck.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Thank you sir for your expertise again.

Very much appreciated.

73s





"Jeff Liebermann" wrote in message
...
On Sun, 2 Aug 2015 07:15:26 -0400, "Tom" wrote:

That is it in a nutshell. I am waiting for approval for the program, If
approved then I can go forward to begin purchasing the system and start
building it.

One more potential problem. Enphase has an online monitoring system
at:
https://enlighten.enphaseenergy.com
https://enlighten.enphaseenergy.com/public_systems
I suggest that you eventually sign up as a system owner. You can
download the data and create your own graphs such as:
http://802.11junk.com/jeffl/solar/380732/total-energy-21040613-20150213.jpg

Incidentally, you can query the Envoy controller directly either via a
web interface or using a graphing program (MRTG):
http://blog.tinle.org/?p=111
http://pvoutput.org
http://pvoutput.org/outputs.jsp
None of the system owners I deal with want me to do this, so I haven't
bothered to try it.

Now that I'm thinking about it, you might run into another problem.
The People's Republic of Santa Cruz (county) uses the NFPA NEC code
which now demands 2ft of clearance between the roof peak and the solar
panels. This clear area is for ventilating the roof should the house
catch fire. I have some issues with this requirement because it
significantly reduces the available roof area for panels for no
benefit because the other side of a typical hip roof is usually clear
of solar panels. You might want to check whether this is a
requirement in your area. I have some docs on the topic if becomes a
problem.

Good luck.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Hi Jeff

Can you comment on the fact that these Enphase converters need 240ac volts
(grid connection) to run? This means that if ever the power supplier
locally ever shuts down for more than a long period of time that these
Enphase units become useless. Around my neck of the woods we are getting
more and more power outages lasting longer and longer. These inverters
require being connected to the grid to function.

I understand the safety requirement and it needing to do this to be
certified but it really limits the home owner (or cottage owner in my case).

Have you ever worked on a system that was more practical? That qualified for
the grid program but was useful when detached from the grid? Seems to me if
ever the power company decides to cancel the program you may be stuck with
40 inverters that are useless and are 200 dollars each.

Any comments are thankful,

Regards

Tom





"Tom" wrote in message
...
Thank you sir for your expertise again.

Very much appreciated.

73s





"Jeff Liebermann" wrote in message
...
On Sun, 2 Aug 2015 07:15:26 -0400, "Tom" wrote:

That is it in a nutshell. I am waiting for approval for the program, If
approved then I can go forward to begin purchasing the system and start
building it.

One more potential problem. Enphase has an online monitoring system
at:
https://enlighten.enphaseenergy.com
https://enlighten.enphaseenergy.com/public_systems
I suggest that you eventually sign up as a system owner. You can
download the data and create your own graphs such as:
http://802.11junk.com/jeffl/solar/380732/total-energy-21040613-20150213.jpg

Incidentally, you can query the Envoy controller directly either via a
web interface or using a graphing program (MRTG):
http://blog.tinle.org/?p=111
http://pvoutput.org
http://pvoutput.org/outputs.jsp
None of the system owners I deal with want me to do this, so I haven't
bothered to try it.

Now that I'm thinking about it, you might run into another problem.
The People's Republic of Santa Cruz (county) uses the NFPA NEC code
which now demands 2ft of clearance between the roof peak and the solar
panels. This clear area is for ventilating the roof should the house
catch fire. I have some issues with this requirement because it
significantly reduces the available roof area for panels for no
benefit because the other side of a typical hip roof is usually clear
of solar panels. You might want to check whether this is a
requirement in your area. I have some docs on the topic if becomes a
problem.

Good luck.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558