Sharp modules [RE-wrenches]

Matt Tritt solarone at charter.net
Tue Mar 1 10:58:55 PST 2005 

<x-flowed>
Your free subscription is supported by today's sponsor:
-------------------------------------------------------------------
Get a FREE* 5 Megapixel Digital Camera - yours to keep!
http://click.topica.com/caadeMobz8Qcsbz9JC9a/5 Megapixel Digital Camera Promotion
-------------------------------------------------------------------

  Bill,

  I did one job that was in the middle of a heavy ground squirrel 
population, which seemed to spell certain doom for any wiring scheme. I 
remembered how a freind had approached this problem once on a boat trailer 
he kept parked in a similar area and applied the solution (literally) to my 
installation. It works.

  I used ground jalapeno pepper mixed with waterproof shelac to make a 
slurry, which was then applied to all the exposed wiring after intallation. 
That was over 10 years ago and the thing still works fine.

  Matt T
  ----- Original Message ----- 
  From: "Bill Brooks" <billb at endecon.com>
  To: <RE-wrenches at topica.com>
  Sent: Tuesday, March 01, 2005 10:50 AM
  Subject: RE: Sharp modules [RE-wrenches]


  Your free subscription is supported by today's sponsor:
  -------------------------------------------------------------------
  Want a laptop? Get an Apple iBook for free!
  http://click.topica.com/caadeMmbz8QcsbadqCja/Amazing Computer
  -------------------------------------------------------------------

  William,

  Matt raises an important issue that I don't hear the conduit proponents
  mention very often. That point is that many module manufacturers that 
offer
  junction boxes do not have conduit ratings on their junction boxes. Has
  everyone checked the conduit rating of their junction boxes? (Shell is the
  only one I know for sure--possibly Kyocera as well) Just because a 
junction
  box has an appropriately-sized knockout does not mean that it is rated by 
UL
  to receive conduit. I have seen many examples (e.g. BP Solar, Solec, 
etc...)
  where the junction boxes worked loose because they were exposed to the
  normal stresses that thermal cycling flex puts on junction boxes.

  Long before MC Cables were available, I supported the idea of 
multiconductor
  cables (TC) being run between modules to comply with the "no conduit" 
issue
  of most junction boxes. TC has its own problems in that it is not fire
  rating (can't run through the house) and I have found that squirrels like 
it
  (over 20 burned out shorts in a 3 kW array from squirrel damage), but I 
have
  to ask if conduit is so much superior given the broken junction boxes 
laying
  on the roof at 600Vdc.

  USE-2 seems to be the best thing going right now. The biggest drawback to
  USE-2 is that it is difficult to keep neat and protected from physical
  damage--many installers connect the MC connectors and drop them on the
  roof--just as bad as squirrels on TC.

  For those that don't like plugs, I would like to see a TC that has rodent
  inhibitors in it. I'm sure it must be available somewhere--anybody know of 
a
  source?

  Bill.


  -----Original Message-----
  From: Matt Tritt [mailto:solarone at charter.net]
  Sent: Tuesday, March 01, 2005 10:02 AM
  To: RE-wrenches at topica.com
  Subject: Re: Sharp modules [RE-wrenches]

    This is only the case if you don't make the run to the combiner with MC
  cables. We have had O problems in using the MC system as designed (and
  employed all over the world) though. I know that there is a divergence of
  opinion on the use of exposed cabling in our business and I have had many
  converstaions with installers in the US and elsewhere about the pros and
  cons of both methods.

    My conclusion, which will not be shared by one and all, is that either
  method can be easily compromised by mischievous intent or honest accident.
  As a matter of fact, the only problems I've ever personally encountered 
with

  panel wiring have been done in flex PVC conduit. In one case, a guy called
  me to look at a sytem installed by others that had stopped working 
properly.

  I discovered that someone (no-doubt a young boy) had pulled hard enough on
  inter-connecting conduit to break the j-boxes loose, pull the conduit from
  the adaptors and rip the wire ends from their connections on a pair of
  panels. The panels were also badly damaged in the process.

    Another situation I encountered was with a job I subbed-out to a 
competent

  electician who used flex conduit to connect panels to inverter on a pair 
of
  tracking systems. The conduit had been incorrectly cut and routed which,
  because of the semi-flexibility of the material and the way it was fixed,
  caused the tracker to bind, which pulled the conduit loose, damaged a J 
box
  and blew a fuse in the tracker.  Since I sold the system, I had to fix the
  systemic problems with this install so it sticks in my memory. I also have
  to admit that back in the "old days" it was common practice to do all 
module

  inter-connections in exposed THHN and/or tray cable. I recently re-visited
  an install I helped do in 81 that was still going strong in spite of the
  crappy looking module inter-connects. No cracks in the insulation, no
  shorts - just several cases where the rubber plugs that Arco used to 
provide

  on their J boxes had fallen out and been replaced with hornet nests. Gulp.
  These were all 12 volt systems of course but still have plenty of 
potential
  for disaster.

    As to Todd's comment on the Cheese Factor of exposed cables, if done 
right

  it doesn't Have to look tacky, but it does take some time to tidy things 
up
  and get everything the right length for the drip loop. (I'm only referring
  to pole mounted systems here, by the way).

    An over complex reply to a nice, simple question if there ever was one!

    Matt T


  Your free subscription is supported by today's sponsor:
  -------------------------------------------------------------------
  Get a FREE* MP3 Player - yours to keep! Click Here Now!
  http://click.topica.com/caadeMpbz8QcsbadqCjf/MP3 Player Giveaway
  -------------------------------------------------------------------

  - - - -
  To send a message: RE-wrenches at topica.com

  Archive of previous messages: 
http://lists.topica.com/lists/RE-wrenches/read

  List rules & etiquette: www.mrsharkey.com/wrenches/etiquette.php

  Check out participant bios: www.mrsharkey.com/wrenches/

  Hosted by Home Power magazine

  Moderator: michael.welch at homepower.com

Your free subscription is supported by today's sponsor:
-------------------------------------------------------------------
2-Day Tax Refund Loans TaxBrain Online Tax Service Get Started 
Now!
http://click.topica.com/caadeMnbz8Qcsbz9JC9f/TaxBrain
-------------------------------------------------------------------

- - - -
To send a message: RE-wrenches at topica.com

Archive of previous messages: http://lists.topica.com/lists/RE-wrenches/read

List rules & etiquette: www.mrsharkey.com/wrenches/etiquette.php

Check out participant bios: www.mrsharkey.com/wrenches/

Hosted by Home Power magazine

Moderator: michael.welch at homepower.com
--^----------------------------------------------------------------
This email was sent to: michael.welch at homepower.com

EASY UNSUBSCRIBE click here: http://topica.com/u/?bz8Qcs.bz9JC9.bWljaGFl
Or send an email to: re-wrenches-unsubscribe at topica.com

For Topica's complete suite of email marketing solutions visit:
http://www.topica.com/?p=TEXFOOTER
--^----------------------------------------------------------------







</x-flowed>

More information about the RE-wrenches mailing list