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Friends:<br><br>
There appears to be a generic problem cropping up with older Sunny Boy
inverters. Here is the scenario and what I have learned so
far:<br><br>
I have a commercial Sunny Boy based client (reportedly the first solar
powered cinema in the US) that has reported a curious problem for the
past few months: The E-total all of a sudden went negative.
This is tallied with a SB Control Light with power line communications
equipment. We have experienced some communications problems and are
preparing to upgrade to RS485 protocol. Because of these
communication problems, I disregarded the problem.<br><br>
I received a call from an early adopter residential customer two days ago
reporting the same problem. I investigated further and the problem
with the commercial installation is not related to the
communications. All inverters that are reporting exhibit the
negative sign on E-total. If you watch the E-total it is slowly
decreasing at the rate of production.<br><br>
SMA Tech support first claimed this as an anomaly that required a
firmware upgrade to repair. This upgrade necessitated ordering a
replacement refurbished inverter at $360.00 each.<br><br>
When pressed, SMA now tells me this is a problem endemic to Sunny Boy SWR
series inverters. Apparently, when the E-total reaches a certain
value, the inverter can't count any higher. It inserts a negative
sign and counts backwards.<br><br>
This problem does not appear to affect production. This is not a
problem if you don't have a display or if you don't look at your
display. This is a problem if you are relying on the e-total value
for any reason. This is a major problem if you have a lobby or web
display and many people are viewing the results.<br><br>
Have any of you experienced this problem?<br><br>
Thanks in advance for sharing your information.<br><br>
<br>
William Miller<br><br>
If you have questions, I will answer next week, after vacation.<br><br>
wm<br><br>
<br>
<x-sigsep><p></x-sigsep>
<font size=3>William Miller <br>
Miller Solar<br>
Voice :805-438-5600<br>
email: william@millersolar.com<br>
<a href="http://millersolar.com/" eudora="autourl">http://millersolar.com<br>
</a>License No. C-10-773985<br>
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