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Colleagues:<br><br>
We are in the middle of our first Enphase installation. I have been
working closely with the crew on this project and dedicated extra time
because we knew we needed to develop some new procedures to accommodate
the new technology.<br><br>
My most surprising realization is that with the Enphase inverters, the
roof-top wiring now has two levels of unprotected wiring, DC <i>and</i>
AC. I have been working on an analogy for the recent
evolution of PV wiring standards and the best I can come up with is that
the new norm is akin to wiring a rooftop air conditioning unit with SO
and USE. Flexible cords are more suited to portable, consumer
connectable appliances in non-harsh environments.<br><br>
We wrestled with two issues: How to secure the AC wiring with a
minimum 10 year longevity -- and how to secure the DC wiring with the
same life expectancy. In a previous career I worked in the
telecommunications industry. In a telcom facility we had access to
many layers of wire routing hardware and systems. The PV industry
has, in my opinion, largely ignored wire management.
Ironically, telecom wiring is low voltage in an industrial setting and we
can secure it systematically, whereas PV wiring is high voltage, often in
a residential setting, outdoors, in high temperature and wet conditions
and yet we are relegated to the ubiquitous and fragile cable tie as our
prime methodology. It is our corporate position that the plastic
cable tie can not be counted on for longer that two years in an under-PV
environment and, since we wire for a minimum 10 year life expectancy, the
plastic cable tie is not suitable.<br><br>
Over the course of two days we developed robust and efficient techniques
for securing the AC and DC wiring. I'd love to share our procedures
with this group, but due to extreme competition in our area, I must of
necessity keep any procedures that give us a competitive advantage
confidential. This is unfortunate as my inclination is to teach,
but it is a reality in this business climate.<br><br>
I hope the industry can eventually recognize some of these short
comings. The solar water industry died an early death because of
economic pressures and shoddy workmanship. It is possible that the
solar electric industry of today can suffer some of the same if we can't
preform to higher standards.<br><br>
William Miller<br><br>
<br>
<x-sigsep><p></x-sigsep>
<font size=3><u>Please note new e-mail address and domain:<br><br>
</u>William Miller <br>
Miller Solar<br>
Voice :805-438-5600 Fax:
805-438-4607<x-tab> </x-tab><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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