[RE-wrenches] Extensive Lightning Damage to Modules

2012-09-07 Thread Jeff Irish
A customer of ours has recently suffered lightning damage to 31 out of 160 top 
of pole mounted modules.  This is the first time in 10 years that I've seen 
modules damaged by lightning.  Lots of inverter GF fuses and a few inverters, 
but never modules.  We're trying to determine if it was caused by the lightning 
flash irradiating the modules or ground currents.

The array consists of 16 DPW top of pole mounts with 10 modules each, arranged 
in a square of 4 poles E-W and 4 rows N-S.  The poles are 13 feet center to 
center E-W and the N-S row spacing is about 50 feet.  The poles are 6 inch 
galvanized Technoposts, augured 5 - 7 feet into the firm ground, connected with 
a network of about 160 feet of bare #6 copper and at least 8 copper plated 
ground rods.  Altogether we have about 130 square feet of bare metal surface 
area connected and buried in the ground at and around the array.

The customer saw lightning strike just after dawn a few weeks ago a couple 
hundred feet to the southwest where it also destroyed two utility pole mount 
distribution transformers and ran along the utility wires 100 feet south of the 
array.  The inverters are 200 feet NW and suffered no damage.  The array and 
modules look totally fine, except some of the J-boxes are deformed from heat.  
Opening the J-boxes shows varying levels of damage to one or more diodes, from 
discoloration to being broken and cracked open.

The odd thing is the pattern of damage (we've tested all the modules 
individually for Voc and Isc).  Only modules in the south row of 4 poles are 
damaged, and the damage is concentrated on the modules closest to the ground; 
modules higher up in the air appear OK.  Also, damage is less frequent as you 
move east, away from the direction of the strike.

If it was caused by ground currents, why would the current want to go up the 
poles, why only the southern row of poles, and why damage more modules closer 
to the ground and not those at the top?  Is it possible a flash near the ground 
irradiated the modules causing a current spike and the southern row shielded 
the other rows from most of the flash?  Anyone have experience with this?


Jeff Irish, PE
President
Hudson Solar
13 Hook Road
Rhinebeck, NY 12572
T.845.876.3767x110
F.845.876.3912
j...@hudsonsolar.commailto:j...@hudsonsolar.com
Solar Electric Systems
NYSERDA Eligible PV Installer
NABCEP Certified Solar PV Installer
NABCEP Certified PV Technical Sales
HudsonSolar.comapplewebdata://B5F2562A-2B67-4161-84E4-42F12DC28720/www.hudsonsolar.com
2011 NYSERDA Excellence in Quality Award | 2011 NYSEIA Award Winner | 2009 Best 
of the Hudson Valley | 2008 SunPower Dealer of the Year | EDC Business 
Excellence Award for Innovation

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Re: [RE-wrenches] Extensive Lightning Damage to Modules

2012-09-07 Thread Larry Crutcher, Starlight Solar Power Systems
Hello Jeff,

I am curious about the network of ground rods and #6 wire. Can you describe how 
the modules and mount are connected to this ground system? 
Are there any tight bends anywhere in the #6 wire? 
Are any of the poles or mounts connected to other poles/mounts before going to 
the ground system? 
Are any PV wires running between the poles before going to the combiner? 

As most wrenches know, lightning strikes can induce very high voltage on any 
nearby wire runs and that voltage is looking for a path to ground. Equipment is 
damaged when it contributes to that path. If the voltage was induced on the PV 
module frames or wire, an effective ground system will disperse it to ground. 
Key word here is effective. I have seen grounding systems where the installer 
made nice, neat and tight 90° bends in the ground wire. This is a huge mistake 
which can greatly diminish the effectiveness of the ground system. 

Larry Crutcher
Starlight Solar Power Systems



On Sep 7, 2012, at 8:40 AM, Jeff Irish wrote:

A customer of ours has recently suffered lightning damage to 31 out of 160 top 
of pole mounted modules.  This is the first time in 10 years that I’ve seen 
modules damaged by lightning.  Lots of inverter GF fuses and a few inverters, 
but never modules.  We’re trying to determine if it was caused by the lightning 
flash irradiating the modules or ground currents. 
 
The array consists of 16 DPW top of pole mounts with 10 modules each, arranged 
in a square of 4 poles E-W and 4 rows N-S.  The poles are 13 feet center to 
center E-W and the N-S row spacing is about 50 feet.  The poles are 6 inch 
galvanized Technoposts, augured 5 – 7 feet into the firm ground, connected with 
a network of about 160 feet of bare #6 copper and at least 8 copper plated 
ground rods.  Altogether we have about 130 square feet of bare metal surface 
area connected and buried in the ground at and around the array.
 
The customer saw lightning strike just after dawn a few weeks ago a couple 
hundred feet to the southwest where it also destroyed two utility pole mount 
distribution transformers and ran along the utility wires 100 feet south of the 
array.  The inverters are 200 feet NW and suffered no damage.  The array and 
modules look totally fine, except some of the J-boxes are deformed from heat.  
Opening the J-boxes shows varying levels of damage to one or more diodes, from 
discoloration to being broken and cracked open. 
 
The odd thing is the pattern of damage (we’ve tested all the modules 
individually for Voc and Isc).  Only modules in the south row of 4 poles are 
damaged, and the damage is concentrated on the modules closest to the ground; 
modules higher up in the air appear OK.  Also, damage is less frequent as you 
move east, away from the direction of the strike. 
 
If it was caused by ground currents, why would the current want to go up the 
poles, why only the southern row of poles, and why damage more modules closer 
to the ground and not those at the top?  Is it possible a flash near the ground 
irradiated the modules causing a current spike and the southern row shielded 
the other rows from most of the flash?  Anyone have experience with this?
 
 
Jeff Irish, PE
President
Hudson Solar
13 Hook Road
Rhinebeck, NY 12572
T.845.876.3767x110
F.845.876.3912
j...@hudsonsolar.com
Solar Electric Systems
NYSERDA Eligible PV Installer
NABCEP Certified Solar PV Installer
NABCEP Certified PV Technical Sales
HudsonSolar.com
2011 NYSERDA Excellence in Quality Award | 2011 NYSEIA Award Winner | 2009 Best 
of the Hudson Valley | 2008 SunPower Dealer of the Year | EDC Business 
Excellence Award for Innovation
 
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Re: [RE-wrenches] Extensive Lightning Damage to Modules

2012-09-07 Thread Kent Osterberg

Jeff,

Is there any surge protection in the combiner boxes? Any damage visible 
in the combiner boxes? Any fuses or breakers open in the combiner boxes? 
Is each pole a single string of modules or multiple strings of modules?


While there where undoubtedly ground currents flowing they probably 
didn't cause the damage in the module junction boxes. The PV module and 
wiring to it form a loop - often a loop with a large area in the 
vicinity of the module. The current from the lightning strike has a 
tremendous dI/dt and the changing magnetic field from it will induce 
voltages in any wire loop.


Kent Osterberg
Blue Mountain Solar, Inc.
www.bluemountainsolar.com
t: 541-568-4882

On 9/7/2012 7:40 AM, Jeff Irish wrote:


A customer of ours has recently suffered lightning damage to 31 out of 
160 top of pole mounted modules.  This is the first time in 10 years 
that I've seen modules damaged by lightning.  Lots of inverter GF 
fuses and a few inverters, but never modules.  We're trying to 
determine if it was caused by the lightning flash irradiating the 
modules or ground currents.


The array consists of 16 DPW top of pole mounts with 10 modules each, 
arranged in a square of 4 poles E-W and 4 rows N-S.  The poles are 13 
feet center to center E-W and the N-S row spacing is about 50 feet.  
The poles are 6 inch galvanized Technoposts, augured 5 -- 7 feet into 
the firm ground, connected with a network of about 160 feet of bare #6 
copper and at least 8 copper plated ground rods. Altogether we have 
about 130 square feet of bare metal surface area connected and buried 
in the ground at and around the array.


The customer saw lightning strike just after dawn a few weeks ago a 
couple hundred feet to the southwest where it also destroyed two 
utility pole mount distribution transformers and ran along the utility 
wires 100 feet south of the array.  The inverters are 200 feet NW and 
suffered no damage.  The array and modules look totally fine, except 
some of the J-boxes are deformed from heat.  Opening the J-boxes shows 
varying levels of damage to one or more diodes, from discoloration to 
being broken and cracked open.


The odd thing is the pattern of damage (we've tested all the modules 
individually for Voc and Isc).  Only modules in the south row of 4 
poles are damaged, and the damage is concentrated on the modules 
closest to the ground; modules higher up in the air appear OK.  Also, 
damage is less frequent as you move east, away from the direction of 
the strike.


If it was caused by ground currents, why would the current want to go 
up the poles, why only the southern row of poles, and why damage more 
modules closer to the ground and not those at the top?  Is it possible 
a flash near the ground irradiated the modules causing a current spike 
and the southern row shielded the other rows from most of the flash?  
Anyone have experience with this?


Jeff Irish, PE

President

Hudson Solar

13 Hook Road

Rhinebeck, NY 12572

T.845.876.3767x110

F.845.876.3912

j...@hudsonsolar.com mailto:j...@hudsonsolar.com

/Solar Electric Systems/

/NYSERDA Eligible PV Installer/

/NABCEP Certified Solar PV Installer/

/NABCEP Certified PV Technical Sales/

HudsonSolar.com 
applewebdata://B5F2562A-2B67-4161-84E4-42F12DC28720/www.hudsonsolar.com


2011 NYSERDA Excellence in Quality Award | 2011 NYSEIA Award Winner | 
2009 Best of the Hudson Valley | 2008 SunPower Dealer of the 
Year | EDC Business Excellence Award for Innovation




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Re: [RE-wrenches] Extensive Lightning Damage to Modules

2012-09-07 Thread dan
I've seen it twice. both were DPW pole Mounts. the first time the whole array was involved (this was a few years ago). At the time, we thought it might be a disgruntled employee because no one had ever heard of such damage. I think we used box lugs and star washers on each module back then). the second just a few weeks ago. this time it seemed totally random affecting about 30% in different strings. Seems back in the broadcast industry we viewed lightening strikes as "Acts of God", and focused more on repair than the "whys". We install as per manufacturer's spec and NEC, and cross our fingers.. But when the Good Lord comes knocking, all bets are off. I remember pulling onto a job site once and found 80 lb chunks of chimney/ fireplace some 150ft down the driveway. Yes, the house did have lightening rods. Good Luck. dbDan BrownFoxfire Energy Corp.Renewable Energy Systems(802)-483-2564www.Foxfire-Energy.comNABCEP #092907-44


 Original Message ----
Subject: [RE-wrenches] Extensive Lightning Damage to Modules
From: Jeff Irish j...@hudsonsolar.com
Date: Fri, September 07, 2012 10:40 am
To: "RE-wrenches@lists.re-wrenches.org"
RE-wrenches@lists.re-wrenches.org

A customer of ours has recently suffered lightning damage to 31 out of 160 top of pole mounted modules. This is the first time in 10 years that I’ve seen modules damaged by lightning. Lots of inverter GF fuses and a few inverters, but never modules. We’re trying to determine if it was caused by the lightning flash irradiating the modules or ground currents.   The array consists of 16 DPW top of pole mounts with 10 modules each, arranged in a square of 4 poles E-W and 4 rows N-S. The poles are 13 feet center to center E-W and the N-S row spacing is about 50 feet. The poles are 6 inch galvanized Technoposts, augured 5 – 7 feet into the firm ground, connected with a network of about 160 feet of bare #6 copper and at least 8 copper plated ground rods. Altogether we have about 130 square feet of bare metal surface area connected and buried in the ground at and around the array.   The customer saw lightning strike just after dawn a few weeks ago a couple hundred feet to the southwest where it also destroyed two utility pole mount distribution transformers and ran along the utility wires 100 feet south of the array. The inverters are 200 feet NW and suffered no damage. The array and modules look totally fine, except some of the J-boxes are deformed from heat. Opening the J-boxes shows varying levels of damage to one or more diodes, from discoloration to being broken and cracked open.The odd thing is the pattern of damage (we’ve tested all the modules individually for Voc and Isc). Only modules in the south row of 4 poles are damaged, and the damage is concentrated on the modules closest to the ground; modules higher up in the air appear OK. Also, damage is less frequent as you move east, away from the direction of the strike.   If it was caused by ground currents, why would the current want to go up the poles, why only the southern row of poles, and why damage more modules closer to the ground and not those at the top? Is it possible a flash near the ground irradiated the modules causing a current spike and the southern row shielded the other rows from most of the flash? Anyone have experience with this?   Jeff Irish, PE President Hudson Solar 13 Hook Road Rhinebeck, NY 12572 T.845.876.3767x110 F.845.876.3912 j...@hudsonsolar.com Solar Electric Systems NYSERDA Eligible PV Installer NABCEP Certified Solar PV Installer  NABCEP Certified PV Technical Sales HudsonSolar.com 2011 NYSERDA Excellence in Quality Award|2011 NYSEIA Award Winner| 2009 Best of the Hudson Valley | 2008 SunPower Dealer of the Year|EDCBusiness Excellence Award for Innovation ___
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Re: [RE-wrenches] Extensive Lightning Damage to Modules

2012-09-07 Thread jay peltz
My 2 cents here is that this is flash irradiance damage.

As there appear to be no burn marks on the module frames right?


Jay
peltz power


On Sep 7, 2012, at 9:29 AM, d...@foxfire-energy.com wrote:

 I've seen it twice. both were DPW pole Mounts. the first time the whole 
 array was involved (this was a few years ago). At the time, we thought it 
 might be a disgruntled employee because no one had ever heard of such damage. 
 I think we used box lugs and star washers on each module back then). the 
 second just a few weeks ago. this time it seemed totally random affecting 
 about 30% in different strings. Seems back in the broadcast industry we 
 viewed lightening strikes as Acts of God, and focused more on repair than 
 the whys. We install as per manufacturer's spec and NEC, and cross our 
 fingers.. But when the Good Lord comes knocking, all bets are off. I remember 
 pulling onto a job site once and found 80 lb chunks of chimney/ fireplace 
 some 150ft down the driveway. Yes, the house did have lightening rods. Good 
 Luck. db
 
 
 Dan Brown
 Foxfire Energy Corp.
 Renewable Energy Systems
 (802)-483-2564
 www.Foxfire-Energy.com
 NABCEP #092907-44
 
 

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Re: [RE-wrenches] Extensive Lightning Damage to Modules

2012-09-07 Thread Jeff Irish
No burn marks on the frames, modules or poles.

Jeff
Hudson Solar

From: re-wrenches-boun...@lists.re-wrenches.org 
[mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of jay peltz
Sent: Friday, September 07, 2012 12:59 PM
To: RE-wrenches
Subject: Re: [RE-wrenches] Extensive Lightning Damage to Modules

My 2 cents here is that this is flash irradiance damage.

As there appear to be no burn marks on the module frames right?


Jay
peltz power


On Sep 7, 2012, at 9:29 AM, 
d...@foxfire-energy.commailto:d...@foxfire-energy.com wrote:


I've seen it twice. both were DPW pole Mounts. the first time the whole array 
was involved (this was a few years ago). At the time, we thought it might be a 
disgruntled employee because no one had ever heard of such damage. I think we 
used box lugs and star washers on each module back then). the second just a few 
weeks ago. this time it seemed totally random affecting about 30% in different 
strings. Seems back in the broadcast industry we viewed lightening strikes as 
Acts of God, and focused more on repair than the whys. We install as per 
manufacturer's spec and NEC, and cross our fingers.. But when the Good Lord 
comes knocking, all bets are off. I remember pulling onto a job site once and 
found 80 lb chunks of chimney/ fireplace some 150ft down the driveway. Yes, the 
house did have lightening rods. Good Luck. db


Dan Brown
Foxfire Energy Corp.
Renewable Energy Systems
(802)-483-2564
www.Foxfire-Energy.comhttp://www.Foxfire-Energy.com/
NABCEP #092907-44



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Re: [RE-wrenches] Extensive Lightning Damage to Modules

2012-09-07 Thread Jeff Irish
Hey Larry,

The four poles of ten modules in each row are each a separate string, combined 
at a fused DC combiner on the west most pole.  A 1 inch PVC conduit runs down 
each pole directly to a buried hand hole box at the west pole of each row.  
Each conduit contains a #8 EGC along with the current carrying conductors.  In 
the hand hole boxes the four #8 wires are irreversibly spliced to the bare #6 
that is laid in and runs the length of the 39 foot trench connecting the four 
poles.  An acorn attaches the bare #6 to a ground rod at each end.  The #8 EGC 
at each pole is irreversibly spliced to the EGC from the rails, rack and pole, 
each of which have lay in lugs.  The module are grounded to the rails with 
WEEBs.  We're following Burndy's paper on how to ground DPW top of pole mounts.

The #6 should not have any tight bends, it should just leave the hand hole box 
and go in a straight line 39 feet east in the bottom of the trench.  This, 
combined with each pole being 5-7 feet into the ground should be sufficient 
grounding, I'd have thought.  It's about 100 times more surface area than the 
average house with a single ground rod.

Jeff
Hudson Solar

From: re-wrenches-boun...@lists.re-wrenches.org 
[mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Larry Crutcher, 
Starlight Solar Power Systems
Sent: Friday, September 07, 2012 11:54 AM
To: RE-wrenches
Subject: Re: [RE-wrenches] Extensive Lightning Damage to Modules

Hello Jeff,

I am curious about the network of ground rods and #6 wire. Can you describe how 
the modules and mount are connected to this ground system?
Are there any tight bends anywhere in the #6 wire?
Are any of the poles or mounts connected to other poles/mounts before going to 
the ground system?
Are any PV wires running between the poles before going to the combiner?

As most wrenches know, lightning strikes can induce very high voltage on any 
nearby wire runs and that voltage is looking for a path to ground. Equipment is 
damaged when it contributes to that path. If the voltage was induced on the PV 
module frames or wire, an effective ground system will disperse it to ground. 
Key word here is effective. I have seen grounding systems where the installer 
made nice, neat and tight 90° bends in the ground wire. This is a huge mistake 
which can greatly diminish the effectiveness of the ground system.

Larry Crutcher
Starlight Solar Power Systems



On Sep 7, 2012, at 8:40 AM, Jeff Irish wrote:


A customer of ours has recently suffered lightning damage to 31 out of 160 top 
of pole mounted modules.  This is the first time in 10 years that I've seen 
modules damaged by lightning.  Lots of inverter GF fuses and a few inverters, 
but never modules.  We're trying to determine if it was caused by the lightning 
flash irradiating the modules or ground currents.

The array consists of 16 DPW top of pole mounts with 10 modules each, arranged 
in a square of 4 poles E-W and 4 rows N-S.  The poles are 13 feet center to 
center E-W and the N-S row spacing is about 50 feet.  The poles are 6 inch 
galvanized Technoposts, augured 5 - 7 feet into the firm ground, connected with 
a network of about 160 feet of bare #6 copper and at least 8 copper plated 
ground rods.  Altogether we have about 130 square feet of bare metal surface 
area connected and buried in the ground at and around the array.

The customer saw lightning strike just after dawn a few weeks ago a couple 
hundred feet to the southwest where it also destroyed two utility pole mount 
distribution transformers and ran along the utility wires 100 feet south of the 
array.  The inverters are 200 feet NW and suffered no damage.  The array and 
modules look totally fine, except some of the J-boxes are deformed from heat.  
Opening the J-boxes shows varying levels of damage to one or more diodes, from 
discoloration to being broken and cracked open.

The odd thing is the pattern of damage (we've tested all the modules 
individually for Voc and Isc).  Only modules in the south row of 4 poles are 
damaged, and the damage is concentrated on the modules closest to the ground; 
modules higher up in the air appear OK.  Also, damage is less frequent as you 
move east, away from the direction of the strike.

If it was caused by ground currents, why would the current want to go up the 
poles, why only the southern row of poles, and why damage more modules closer 
to the ground and not those at the top?  Is it possible a flash near the ground 
irradiated the modules causing a current spike and the southern row shielded 
the other rows from most of the flash?  Anyone have experience with this?


Jeff Irish, PE
President
Hudson Solar
13 Hook Road
Rhinebeck, NY 12572
T.845.876.3767x110
F.845.876.3912
j...@hudsonsolar.commailto:j...@hudsonsolar.com
Solar Electric Systems
NYSERDA Eligible PV Installer
NABCEP Certified Solar PV Installer
NABCEP Certified PV Technical Sales
MailScanner has detected a possible fraud attempt from applewebdata

Re: [RE-wrenches] Extensive Lightning Damage to Modules

2012-09-07 Thread Kent Osterberg
When a long circuit has surge protection at only one end, the voltage at 
the unprotected end of the wire will rise, by induction, during a 
lightning event that causes the surge protection to activate. There 
should be surge protection at both ends of long feeders to reduce 
possible damage from induced voltages.


Kent Osterberg
Blue Mountain Solar, Inc.
www.bluemountainsolar.com
t: 541-568-4882


On 9/7/2012 11:14 AM, Jeff Irish wrote:


Kent,

Surge protection is at the inverters, 200 feet away, on both the AC 
and DC sides.  Nothing at the array; never thought we'd need it 
there.  There's a 4 string fused DC combiner on the west pole of each 
row; no damage visible on any of them and their fuses were all ok.  
And yes, each pole of 10 modules is a separate DC string, 4 are 
combined into a DC output circuit to each of four SB7000US inverters.


Jeff

Hudson Solar

*From:*re-wrenches-boun...@lists.re-wrenches.org 
[mailto:re-wrenches-boun...@lists.re-wrenches.org] *On Behalf Of *Kent 
Osterberg

*Sent:* Friday, September 07, 2012 11:56 AM
*To:* RE-wrenches
*Subject:* Re: [RE-wrenches] Extensive Lightning Damage to Modules

Jeff,

Is there any surge protection in the combiner boxes? Any damage 
visible in the combiner boxes? Any fuses or breakers open in the 
combiner boxes? Is each pole a single string of modules or multiple 
strings of modules?


While there where undoubtedly ground currents flowing they probably 
didn't cause the damage in the module junction boxes. The PV module 
and wiring to it form a loop - often a loop with a large area in the 
vicinity of the module. The current from the lightning strike has a 
tremendous dI/dt and the changing magnetic field from it will induce 
voltages in any wire loop.


Kent Osterberg
Blue Mountain Solar, Inc.
www.bluemountainsolar.com  http://www.bluemountainsolar.com
t: 541-568-4882
  


On 9/7/2012 7:40 AM, Jeff Irish wrote:

A customer of ours has recently suffered lightning damage to 31
out of 160 top of pole mounted modules.  This is the first time in
10 years that I've seen modules damaged by lightning.  Lots of
inverter GF fuses and a few inverters, but never modules.  We're
trying to determine if it was caused by the lightning flash
irradiating the modules or ground currents.

The array consists of 16 DPW top of pole mounts with 10 modules
each, arranged in a square of 4 poles E-W and 4 rows N-S.  The
poles are 13 feet center to center E-W and the N-S row spacing is
about 50 feet.  The poles are 6 inch galvanized Technoposts,
augured 5 -- 7 feet into the firm ground, connected with a network
of about 160 feet of bare #6 copper and at least 8 copper plated
ground rods. Altogether we have about 130 square feet of bare
metal surface area connected and buried in the ground at and
around the array.

The customer saw lightning strike just after dawn a few weeks ago
a couple hundred feet to the southwest where it also destroyed two
utility pole mount distribution transformers and ran along the
utility wires 100 feet south of the array.  The inverters are 200
feet NW and suffered no damage.  The array and modules look
totally fine, except some of the J-boxes are deformed from heat. 
Opening the J-boxes shows varying levels of damage to one or more

diodes, from discoloration to being broken and cracked open.

The odd thing is the pattern of damage (we've tested all the
modules individually for Voc and Isc).  Only modules in the south
row of 4 poles are damaged, and the damage is concentrated on the
modules closest to the ground; modules higher up in the air appear
OK.  Also, damage is less frequent as you move east, away from the
direction of the strike.

If it was caused by ground currents, why would the current want to
go up the poles, why only the southern row of poles, and why
damage more modules closer to the ground and not those at the
top?  Is it possible a flash near the ground irradiated the
modules causing a current spike and the southern row shielded the
other rows from most of the flash?  Anyone have experience with this?

Jeff Irish, PE

President

Hudson Solar

13 Hook Road

Rhinebeck, NY 12572

T.845.876.3767x110

F.845.876.3912

j...@hudsonsolar.com mailto:j...@hudsonsolar.com

/Solar Electric Systems/

/NYSERDA Eligible PV Installer/

/NABCEP Certified Solar PV Installer/

/NABCEP Certified PV Technical Sales/

*MailScanner has detected a possible fraud attempt from
applewebdata: claiming to be* HudsonSolar.com
applewebdata://B5F2562A-2B67-4161-84E4-42F12DC28720/www.hudsonsolar.com

2011 NYSERDA Excellence in Quality Award | 2011 NYSEIA Award
Winner | 2009 Best of the Hudson Valley | 2008 SunPower Dealer of
the Year | EDC Business Excellence Award for Innovation





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Re: [RE-wrenches] Extensive Lightning Damage to Modules

2012-09-07 Thread Solarguy
In 2006 we installed a dozen Spire 85W modules w/clear backing in pairs as
skylights. Shortly after, the building attached to the electrical equipment
room, took a direct lightning strike to the wind anemometer 10 feet above
the roof. Of the 12 modules four suffered damage to their diodes. Several
were completely vaporized, there was nothing remaining except powder and the
leads. Others had burnt diodes with leads that had clearly been very hot.
Other modules were just fine, the damage seemed to be random with all 12 in
series. 

The 4 trackers, the closest ~70 ft. away, are grounded with two spools of
buried #8 bare copper and Uffer grounds in the concrete piers were
untouched. Delta SS's at the tracker discos and in the inverter room were
unaffected which I thought was odd. 5 Sunny boys  2 Sunny Islands in the
same room were toasted. Our only experience with lightning. 

 

Jim Duncan

North Texas Renewable Energy Inc

www.ntrei.com http://www.ntrei.com/  

NABCEP PV 031310-57

TECL-27398

nt...@1scom.net 

817.917.0527

 

 

 

 

 

From: re-wrenches-boun...@lists.re-wrenches.org
[mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Jeff Irish
Sent: Friday, September 07, 2012 9:41 AM
To: RE-wrenches@lists.re-wrenches.org
Subject: [RE-wrenches] Extensive Lightning Damage to Modules

 

A customer of ours has recently suffered lightning damage to 31 out of 160
top of pole mounted modules.  This is the first time in 10 years that I've
seen modules damaged by lightning.  Lots of inverter GF fuses and a few
inverters, but never modules.  We're trying to determine if it was caused by
the lightning flash irradiating the modules or ground currents.  

 

The array consists of 16 DPW top of pole mounts with 10 modules each,
arranged in a square of 4 poles E-W and 4 rows N-S.  The poles are 13 feet
center to center E-W and the N-S row spacing is about 50 feet.  The poles
are 6 inch galvanized Technoposts, augured 5 - 7 feet into the firm ground,
connected with a network of about 160 feet of bare #6 copper and at least 8
copper plated ground rods.  Altogether we have about 130 square feet of bare
metal surface area connected and buried in the ground at and around the
array. 

 

The customer saw lightning strike just after dawn a few weeks ago a couple
hundred feet to the southwest where it also destroyed two utility pole mount
distribution transformers and ran along the utility wires 100 feet south of
the array.  The inverters are 200 feet NW and suffered no damage.  The array
and modules look totally fine, except some of the J-boxes are deformed from
heat.  Opening the J-boxes shows varying levels of damage to one or more
diodes, from discoloration to being broken and cracked open.  

 

The odd thing is the pattern of damage (we've tested all the modules
individually for Voc and Isc).  Only modules in the south row of 4 poles are
damaged, and the damage is concentrated on the modules closest to the
ground; modules higher up in the air appear OK.  Also, damage is less
frequent as you move east, away from the direction of the strike.  

 

If it was caused by ground currents, why would the current want to go up the
poles, why only the southern row of poles, and why damage more modules
closer to the ground and not those at the top?  Is it possible a flash near
the ground irradiated the modules causing a current spike and the southern
row shielded the other rows from most of the flash?  Anyone have experience
with this?

 

 

Jeff Irish, PE

President

Hudson Solar

13 Hook Road

Rhinebeck, NY 12572

T.845.876.3767x110

F.845.876.3912

j...@hudsonsolar.com

Solar Electric Systems

NYSERDA Eligible PV Installer

NABCEP Certified Solar PV Installer 

NABCEP Certified PV Technical Sales

HudsonSolar.com
applewebdata://B5F2562A-2B67-4161-84E4-42F12DC28720/www.hudsonsolar.com 

2011 NYSERDA Excellence in Quality Award | 2011 NYSEIA Award Winner | 2009
Best of the Hudson Valley | 2008 SunPower Dealer of the Year | EDC Business
Excellence Award for Innovation

 

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