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Fellow wrenches,<br>
<br>
I've got a question for those wrenches that have grid-connected
inverters in locations where the utility uses remote meter reading
technology - hey it's going to be everywhere soon. Are you seeing
compatibility problems with grid-connected inverters and the
utility's meter reading signals? <br>
<br>
The utility here has been installing a remote meter reading system
that uses TWACS. You can read about TWACS on the <a
href="http://www.aclaratech.com/AclaraPLS/Pages/specsheets.aspx">ACLARA
website</a> but they divulge very little technical information.
For that you have to dig a bit to find that the TWACS signal is
generated by firing a SCR through a small inductor that's connected
L1 to L2. The firing happens near the zero crossing of the 60 Hz
waveform and seems to be messing up a lot of devices including some
microinverters. If you have data monitoring, the inverters react as
if the voltage/frequency is out of tolerance and shut down for five
minutes. The daily power graph has multiple steep power drops
lasting five minutes at times when smooth continuous power is
expected.<br>
<br>
It would be good if we could identify which inverters have
compatibility problems for various technologies. <br>
<br>
<pre class="moz-signature" cols="72">--
Kent Osterberg
Blue Mountain Solar, Inc.
<a class="moz-txt-link-abbreviated" href="http://www.bluemountainsolar.com">www.bluemountainsolar.com</a>
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