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I am guessing that this contractor's bad experience with this is
from the RF noise (EMI) that the inverters or charge controllers
make.<br>
This interference can mess up Zigbee and other communications
means for sure. I'm not positive, but Zigbee may be more prone to<br>
EMI interference than some other communications methods but you
have to work with what you got I guess.<br>
The interference can usually be reduced by adding some filtering
to the PV system as well as wiring in conduit (etc.) but if it
really<br>
turns out to be a problem at a home, then another EMI/RFI
mitigating contractor may be required to help.<br>
<br>
Another thing that can help is to just make sure the Zigbee or
whatever wins out over the interference by using directional<br>
antennas, cranking up the transmit power (if legal), etc.<br>
<br>
Having said that, I don't think that the problem this contractor
talks about is always a problem. Sometimes you<br>
get lucky and sometimes you are unlucky in these installations.
It's not the DC at least, it's the AC (RF) that is<br>
riding on the DC that is the problem and comes from the equipment
that the PV is hooked up to.<br>
<br>
boB<br>
<br>
<br>
<br>
On 7/28/2014 9:31 PM, <a class="moz-txt-link-abbreviated" href="mailto:scot.arey@solarcentex.com">scot.arey@solarcentex.com</a> wrote:<br>
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<div>I am installing a ground array for a customer who has a
highly automated home. He calls tonight and says his
automation contractor says that solar PV systems within 300
feet of the home will degrade the home automation
communications which are Zigbee-based he says.</div>
<div><br>
</div>
<div>I think it's the craziest thing I've ever heard… but he's
paying and I need to look into this and get affirmative
answers.</div>
<div><br>
</div>
<div>My 10.8KW ground array will be 300 feet away (yes -
accounting for voltage drop!) and connect at a load side
meter box connection.</div>
<div><br>
</div>
<div>Anybody hear anything like this? Can the DC flow of
electrons really cause this degrading effect?</div>
<br>
</div>
<div data-signatureblock="true">
<div><br>
</div>
<div>Howard "Scot" Arey<br>
<br>
Solar CenTex<br>
254-300-1228<br>
<br>
"Use the Texas Sun!"</div>
<br>
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