Troubleshooting Atlantis Sunslates- full Isc with little/no Imp [RE-wrenche

Tue Aug 10 12:53:26 PDT 2004

<x-flowed>

Your free subscription is supported by today's sponsor:
-------------------------------------------------------------------
Amazing Diet Patch
The fastest - Easiest way to lose weight! Try it now FREE!
http://click.topica.com/caacvgtbz8Qcsbz9JC9a/MyDietPatches
-------------------------------------------------------------------

Nick,
I'm not sure what you are asking for here. A check on your 
methodology or our opinion that the Sunslates are trashed and we 
agree with you?
Personally, I've stayed away from the slates until they prove 
themselves. Sounds like "not ready for prime time" yet, based on your 
experiences and others I seem to recall.
Likely some of the slates are bad. Just one or two in a string could 
be bogus and still show good Voc and Isc. Since you have a combiner 
box, can you /have you tested the strings while hooked up to the 
battery individually? That will give you a better picture of the 
current out of the string under load. To find the individual rotters, 
you'll pretty much have to do a individual slate voltage test while 
hooked to the battery. You'll likely find the rotter has low voltage 
while it's neighbor is going high. That sort of test seems like a 
hell of a lot of work given you've got 24 in a string and the 
freakin' things are screwed down to boot.
So I can see why you'd ask for a full replacement. My question is: 
who pays for the re-roofing job? Sunslate or you?
Good Luck, Bob-O

>Hello wrenches:
>     Thanks, in advance!
>     I am troubleshooting a grid-tied, battery based system my company
>installed six years ago, and I could use some good advice.
>     The system consists of two grid-tied SW-5548 inverters with 24- 1770
>A/HR C&D Technology batteries, and 10 KW of Atlantis Sunslate Solar Shingles
>located on three roofs.
>     Each roof of modules consists of 13 strings of Sunslates.  Each series
>string consists of twenty four Sunslates.  Each roof's strings are wired in
>parallel at a fused, Pulse combiner box.  Each string has a Voc of 70 VDC,
>and the Isc for each string is around 4.2 A.  We have one combiner box for
>each roof, and each combiner box has a 60A breaker in the Pulse DC load
>center
>     Two of the roofs strings produce little, or no power.  When first
>installed, each roof would put out 40 Amps on a sunny day.  This fall we
>recorded 26 Amps per roof on the two,  upper, low sloped roofs.  At the time
>but the lower roof had a bad string.  Surprisingly, since Atlantis no-longer
>manufactured the same slate with a cell that looked similar, they replaced
>the entire roof with new Sunslates!  Now, the new, lower roof is working,
>but the upper roofs seem to be failing.
>     When measured with my ampclamp, some of the individual strings produced
>only .2A and some produced as high as 1.5 A in ~900 watts/meter sq
>insolation.  (1 pm on August 9, in Grass Valley, CA)
>     I checked all the wiring connections, and tested for voltage drops in
>the wiring, with no problems found.
>     I bypassed the combiner boxes output around the Pulse charge controller
>in the PSC-500 enclosure.  The roofs' output was not related to the charge
>controller or it's settings.
>     I can assure you that the inverter programming is not a factor.  The
>inverters are in Line-tie mode, and consistently send 70A (was 125A) at 54
>VDC to the utility grid, but when the lower roof's breakers are opened, but
>the upper roofs breakers are closed, then the system output drops to 17A at
>54 VDC.  This 17 Amps is consistent with the Imp readings from the two upper
>roofs
>     It is my theory that many of the Sunslates are failing, and the two
>upper roofs must be replaced.  Does anyone else agree with me???
>     One of these roofs was replaced in 98' because the array had volts, but
>no amps.  It turned out that the Sunslates were shorting on a CONDUCTIVE
>GREASE in the Sunslates j-box.
>     I want to commend Atlantis on providing quality service and support for
>our customers' problems in the past, and we have enjoyed working with them
>on many projects, including PV USA and the Kit Carson School.  I expect that
>they will work with us to find a solution.  Right now, I am in the "we'll
>have to call you back," stage, so I am looking for some outside input.
>
>Nick Soleil
>Alternative Power Systems
>www.alternativepowersystems.com
>nicks at alternativepowersystems.com
>135 Colfax Ave.
>Grass Valley, CA 95945
>Grass Valley, CA 95945
>(530) 274-0588 phone
>(530) 274-0589 fax

-- 
Bob-O Schultze, Electron Connection
PO Box 203, Hornbrook, CA 96044
800.945.7587 or 530.475.3402
fax 530-475-3401
www.electronconnection.com

Your free subscription is supported by today's sponsor:
-------------------------------------------------------------------
Save up to 67% on Omaha Steaks + Get 6 FREE Burgers and a 
FREE Cutlery Set + Cutting Board!
http://click.topica.com/caacvgpbz8Qcsbz9JC9f/OmahaSteaks
-------------------------------------------------------------------

- - - -
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/etiquete.htm

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>