GaryGlad they are working with youAs per chokes type 31 or 75 depends on the
frequency you trying to suppress RFI EMI Filters from Corcom are nice but
expensiveIn situations where the Noise EMI is terminated in a low impedance or
effectivelyAn open circuit with lossy material has affects on how it gets
suppressed and radiatedSometimes Common mode suppression is not enough and that
where EMIFilters suppress Non Common Modes issuesGood Luck73 MikeWB6DJI
Sent from AOL Mobile Mail
Get the new AOL app: mail.mobile.aol.com
On Friday, August 23, 2019, Gary Johnson <gwj@wb9jps.com> wrote:
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@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
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
|