Re: [RE-wrenches] Wiley Asset
<mailto:re-wrenches@lists.re-wrenches.org> Hi Matt: Thanks for your opinions. Just a couple comments. 1. Azimuths. We fixed this issue some time ago. 2. Too many steps. Except for large rooftop installations, most sites can really be analyzed with a good eye and a compass. The purpose of a shading tool is documentation. There are always trade offs in engineering design. The positive benefit of the ASSET is that the resulting panoramic image is an undistorted view from the location. All other tools have a fish-eye perspective, which, in my opinion, makes it difficult to communicate details of the shading to a customer or inspector. When you consider the total time assessing a site, documenting locations of utility interconnect, wiring runs, etc. the survey many times itself is just a small part of your time. There will always be some personal preferences in choosing a tool. It's nice to have three choices where once there was only one. Best Regards, Brian Wiley Wiley Electronics LLC On 9/9/2010 7:00 PM, Skip Towne wrote: I checked out this instrument when it came out a couple years ago. In my opinion, there were two fatal flaws with it. 1. It only evaluates azimuths +/- 45 degrees of true south... 2. It required too many steps. I.e. Shoot at least 7 images; Download to your computer; Stitch the images together into a single file; Run the analysis; Generate the report... I discussed these issues with the Wiley folks and they pretty much didn't think any of this was a problem... Don't know if they have addressed these issues or not. From reading the manual again, it looks like they have not. Compared to the Solmetric SunEye, it's too limited, too complicated, and has too many chances for errors. The SunEye is a professional tool. The ASSET is not. $0.02001 -Matt Lafferty On Wed, Sep 8, 2010 at 2:46 PM, benn kilburn <mailto:b...@daystarsolar.ca>> wrote: Wrenches, I'm looking at trying out another 'solar site evaluation tool', the ASSET (Acme Solar Site Evaluation Tool) from Wiley Electronics. I'm looking for feedback on its performance and user-ability. I have been using the pathfinder which is great, but not the pathfinder software. Any comments on the ASSET or Pathfinder software would be greatly appreciated. Cheers, benn DayStar Renewable Energy Inc. b...@daystarsolar.ca <mailto:b...@daystarsolar.ca> 780-906-7807 HAVE A SUNNY DAY ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org <mailto:RE-wrenches@lists.re-wrenches.org> Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm <http://www.re-wrenches.org/etiquette.htm> Check out participant bios: www.members.re-wrenches.org <http://www.members.re-wrenches.org> ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options& settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules& etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.851 / Virus Database: 271.1.1/3126 - Release Date: 09/10/10 03:08:00 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
[RE-wrenches] WEEBs, codes, and standards
Wrenches, Please allow me to add my views. The NEC clearly spells out acceptance of the WEEB. In addition, the WEEB parts are listed to the standard for grounding and bonding, ANSI/UL 467, by Intertek ETL. The problem is that some are not satisfied that this meets all the needs of an outdoor DC installation like PV. Since ANSI/UL1703 (Standard for Flat-plate Photovoltaic Modules and Panels) does not cover grounding components or racking, UL has decided, in effect, to make the module manufacturers responsible for PV grounding. They have added their own test requirements (which are not part of 1703 or any other standard) for modules submitted to them, one of which is that the module manufacturers must approve every piece of grounding equipment they want to have used with their modules. They must submit these grounding components for testing with the module. Only UL listed grounding components may be submitted to UL. Intertek ETL has also followed this non-standard testing, but allows any listed grounding components to be used. I do not know the policy of CSA or TUV. Testing a product without application of an ANSI or other consensus standard actually violates the OSHA requirements for an NRTL, but I have been reluctant to be the one to point this out to OSHA. As you can imagine most module manufacturers do not want to pay to have every piece of grounding equipment tested and so have generally only picked a few methods to be approved for their installation manual. Ironically, as Bill Brooks pointed out, some of the methods which have been approved violate the listing of the specified grounding equipment. The Department of Energy has funded the SolarABCs to address these types of problems, but thus far have ignored this one. In general, I find wrenches to be under represented in these types of standards and code discussions. If you would like your opinion to be heard, please feel free to copy your posting to Larry Sherwood, Project Administrator of the SolarABCs, at la...@sherwoodassociates.com <mailto:la...@sherwoodassociates.com>This e-mail address is being protected from spambots. You need JavaScript enabled to view it . Best Regards, Brian Wiley Wiley Electronics LLC On 9/13/2010 2:50 PM, Marco Mangelsdorf wrote: One point of clarification regarding SunPower Corp. and WEEBs having just had communication with them today on this subject. SunPower has yet to officially approve/sign off on the use of WEEBs with their metal-framed modules. They have been exploring the issue but have yet to give their seal of approval on the WEEB as a grounding means for their modules. marco Hi Bill; 690.43 seems to practically spell out acceptance of the WEEB. and then it cross references article 250.136A. 250.136 EQUIPMENT CONSIDERED GROUNDED "(A)Electrical equipment secured to and in electrical contact with a metal rack or structure provided for its support" (Is it the undefined "in electrical contact"?) Third, in the NEC 2008 hand book, Exhibit 250.53 shows several generic (j-boxes, could be any electrical device?) mounted to a metal rack, with one bonding jumper from the rack to ground. It seems to make a case that we don't even need the WEEB, that star washers on bolts to the frame would be acceptable, as long as the frame were grounded. On an Outback prewired powerboard (for example), all the equipment is considered grounded (and passes as a UL assembly) simply by being bolted altogether on a powder coated steel backing plate. Is this also a voltage issue, for arrays over 250 v? I'm sure I'm missing something. I recall you once saying that UL doesn't even use the grounding hole when testing modules, that they just clamped an alligator clip to the frame? Thanks for giving us the "NEC and beyond" viewpoint, Ray Walters We need a more generic approach to grounding and that is what is currently underway. Amen Grounding and bonding is extremely important and jurisdictions are focused on it for obvious safety reasons. We need solutions that are clearly reliable and straightforward so that installers and jurisdictional authorities don't have to constantly be revisiting the issue. Bill. -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Peter Parrish Sent: Monday, September 13, 2010 7:18 AM To: 'RE-wrenches' Cc: 'Christopher Flueckiger'; 'Tim Zgonena' Subject: Re: [RE-wrenches] The Demise of Reason Bill (and Chris and Tim), "Be a little bit more careful in your choice of subjects..."? I am shocked, shocked that you would use that tone with me. If you would re-read my post, I talked about three things: (1) SunPower's no longer supporting the WEEB clip technology and regressing to the ILSCO GBL-4DBT. You are right about the insertion of the star washer betwe
Re: [RE-wrenches] The Demise of WEEB
Mr. Truitt, You are obviously a talented installer, but please allow me to comment on your point number 2. The clip acts something like a mini-rivet and will still be connected when the clamp is loosened. You will have to yank the clip off and possibly damage it, which is why they are recommended for one-time use. A tin-plated lug will last, but it is the attachment to an anodized aluminum frame that may not. Many are installed with a stainless steel thread forming screw. The original installer might have carelessly stripped the threads or screwed it in multiple times so that the connection was not that good to start with. We have also seen that in a high salt environment the formed thread is a place for corrosion to begin and over time, the screw hole can corrode until the lug falls off! I would recommend the safest practice is to assume that there will not be a ground when you remove any module. Best Regards, Brian Wiley Wiley Electronics LLC 845.247.6163 www.we-llc.com On 9/14/2010 1:31 AM, Andrew Truitt wrote: 2 points: 1) For the sake of clarity: there are WEEB LUGS <http://www.we-llc.com/Datasheets/204-0404-03.pdf> and WEEB CLIPS <http://www.we-llc.com/Datasheets/204-0404-07.pdf>. WEEB Lugs are comprised of very robust tin-plated copper lugs, stainless steel hardware, and the actual WEEB, which is the stainless steel nippled "washer" that pierces aluminum anodization. WEEB Clips are simply stainless steal nippled washers that are installed between module and rail that form a bond, theoretically eliminating the need to bond the module to a ground wire, so long as the rails are properly grounded. 2) My biggest concern with the WEEB Clip is that the moment a top-clamp is loosened the module is no longer grounded!!! To me that is not a good grounding method. Mr Wiley is obviously a talented inventor and he makes a strong argument for the quality of the bond that the WEEB Clip provides when the clip is installed properly and all mounting hardware is properly torqued. What I don't understand is the argument that this is as safe of a product as a properly installed outdoor rated lug for the service tech who has to work on that array. A tin-plated copper lug with a stainless steel set screw will last. A service tech working on a faulted array that was grounded with WEEB Clips might not. Andrew Truitt Free agent Golden, CO. On Mon, Sep 13, 2010 at 10:04 PM, benn kilburn <mailto:b...@daystarsolar.ca>> wrote: Hopefully any crew installing PV, and familiar with this debate (which they should be) can easily distinguish between the GBL-4 and the GBL-4DBT. The weight difference is quite noticeable. If it feels light for its size, it's aluminum, dont use it!!! If it has some distinct weight to it, then it's most likely the copper DBT, giv'er! So what other non-conductive materials are out there that could help resolve this frame bonding issue? Sunteck's BIPV SolarBlend module uses a polycarbonate frame which requires no bonding. Do any of you have any experiences with these? How were they to handle, install? Do they offer any hope or support for non-metallic module frames? benn DayStar Renewable Energy Inc. b...@daystarsolar.ca <mailto:b...@daystarsolar.ca> 780-906-7807 HAVE A SUNNY DAY From: r...@solarray.com <mailto:r...@solarray.com> Date: Mon, 13 Sep 2010 11:14:36 -0600 To: re-wrenches@lists.re-wrenches.org <mailto:re-wrenches@lists.re-wrenches.org> Subject: Re: [RE-wrenches] The Demise of WEEB I didn't do the original install, and I couldn't ID the lug because of the corrosion. I believe everyone is correct that this isn't the DBT rated lug, though. Another reason to use the WEEB: a crew can't accidentally install the wrong (but almost identical, when new) lug. I'm sure the non-DBT lugs got mixed together in a bin at some point. R. Walters r...@solarray.com <mailto:r...@solarray.com> Solar Engineer On Sep 12, 2010, at 5:41 PM, Jamie Johnson wrote: That looks like a tin plated aluminum lug (aluminum corrosion) with a plated steel screw (rusted screw)... Here is an explanation of the differences between both ILSCO GBL 4 lugs from John Wiles Code Corner in Homepower issue 102 "The Ilsco GBL-4DBT is a lay-in lug made of solid copper, which is then tin-plated. It has a stainless steel screw to hold the wire. The lug accepts a #14 (2 mm2) to #4 (21 mm2) copper conductor. It is listed for direct burial (DB) and outdoor use and can be attached to aluminum structures (the tin plate). The much cheaper Ilsco GBL-4
Re: [RE-wrenches] Incompatible Metals
Hi Mick, WEEB lugs can use either solid or stranded. One wire up to 6 AWG or two wires of 10AWG. Best Regards, Brian Wiley Wiley Electronics LLC On 1/14/2011 8:15 PM, Mick Abraham wrote: Kindly bear with me as I go "back to basics". #10 cu has been my old standby for bonding the metal solar module frames but in recent years Arthur Ruden @ Sharp told me to use nothing smaller than #8. I don't know if other major PV mfr's have a similar spec or not but before I buy a spool... The new (and appealing) Tyco SolKlamp product calls for solid wire only, not stranded, if I recall correctly. I've never used the solid material because of the bending difficulty but I now wonder if other grounding methods: WEEB lugs, lay-in lugs, etc. also prefer the use of a solid grounding conductor instead of stranded. Opinions and education are welcomed. As always, the Wrench List is the Bomb! Mick Abraham, Proprietor www.abrahamsolar.com <http://www.abrahamsolar.com> Voice: 970-731-4675 On Fri, Jan 14, 2011 at 12:45 PM, Kelly Keilwitz, Whidbey Sun & Wind mailto:ke...@whidbeysunwind.com>> wrote: Peter, Yes the #10 XHHW (2) we use is green-jacketed, and 90˚ rated. We get it through our local electrical supply house. Kelly Keilwitz, P.E. Whidbey Sun & Wind Renewable Energy Systems ke...@whidbeysunwind.com <mailto:ke...@whidbeysunwind.com> 360-678-7131 On Jan 14, 2011, at 11:04 AM, Peter Parrish wrote: Great idea Kelly! I didn't know one could get green jacketed USE or XHHW. Do you have a source? Also, do you think that we might need wire rated "-2" for 90 deg C wet locations. I know that this is not a current carrying conductor, but roof tops are definitely 90 deg C wet environments. Your thoughts? - Peter Peter T. Parrish, Ph.D., President California Solar Engineering, Inc. 820 Cynthia Ave., Los Angeles, CA 90065 CA Lic. 854779, NABCEP Cert. 031806-26 peter.parr...@calsolareng.com <mailto:peter.parr...@calsolareng.com> Ph 323-258-8883, Mobile 323-839-6108, Fax 323-258-8885 -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org <mailto:re-wrenches-boun...@lists.re-wrenches.org> [mailto:re-wrenches-boun...@lists.re-wrenches.org <mailto:re-wrenches-boun...@lists.re-wrenches.org>] On Behalf Of Kelly Keilwitz, Whidbey Sun & Wind Sent: Friday, January 14, 2011 10:14 AM To: RE-wrenches Subject: Re: [RE-wrenches] Incompatible Metals Peter, I have never understood the common practice of using bare copper ground wire on and against aluminum frames and modules. It always has been a dissimilar metals issue. Just look anywhere copper has set against aluminum for awhile. We use #10 green jacketed Cu USE or XHHW conductor and strip away the jacket at each lug, using No-Ox on that section of bare wire at the lug. The wire can be tucked in to the module frames and with the PV conductors. Kelly Keilwitz, P.E. Whidbey Sun & Wind Renewable Energy Systems ke...@whidbeysunwind.com <mailto:ke...@whidbeysunwind.com> 360-678-7131 On Jan 14, 2011, at 7:36 AM, Peter Parrish wrote: One of my students who is currently responsible for standing for inspection at their company encountered a inspector who made an interesting point about incompatible metals (i.e. copper and anodized aluminum). The PV system in question used outdoor rated lay-in lugs to bond the rails to bare copper wire (so far so good). The ground wire was then zip- tied to the rail to carry it to the point where it entered a junction box along with the rest of the PV conductors. The inspector was concerned with the fact that the bare copper was in contact with the aluminum rails and that this might cause galvanic corrosion and subsequent failure of the grounding. I have never encountered this issue before and I wonder if anyone else has and what was the outcome. As an aside: I do know that 10 AWG and 12 AWG solid bare copper wire can be purchased "pre-tinned" (maybe not tin per se, but coated). We did so by mistake. We used it up, but not before one inspector questioned its use for the purp
[RE-wrenches] Solar World Poly
Mr. Miller, With regard to which frames will work with the Acme clips, I think you should request the 2.5 frame and not the 2.0 frame. http://www.solarworld-usa.com/system-designers/~/media/Global/PDFs/datasheets/sunmodule-solar-panel-245-poly-ds.pdf -- Best Regards, Brian Wiley Wiley Electronics LLC ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules
Hi August, I maintain that the WEEB is an irreversible splice. If you want to disconnect a WEEB from a structure, you must irreversibly damage the device. It cannot be reused. Admittedly the force required to remove a WEEB is less than that required for a thermal splice, but it doesn't take much force to just cut a wire either. I would argue that the intent of the code is to prevent inadvertent removal of the ground. You must knowingly remove a WEEB from the grounding path and if you do so in the maintenance of an array, good workmanship requires that you restore the connection. Best Regards, Brian Wiley On 1/15/2013 2:11 PM, August Goers wrote: Hi John, I definitely see your point and that is why I was somewhat questioning the use of WEEBs with Enphase below. Enphases's instructions (link posted in thread below) seem to indicate a support of running the continuous GEC on the rack and then bonding the microinverter to the rack with WEEBs. Maybe I am misinterpreting the document or perhaps Enphase has another take. There is no question that according to NEC 250.64(C) the GEC must be continuous. In the 2008 NEC handbook section 690.42 Point of System Grounding Connection has an application note "Connections are to be made in accordance with markings on the equipment or in the installation instructions." All that said, it seems like technology is leaning towards listed AC Modules or floating array inverters. It sounds like that removes the requirement for a GEC which is great to help reduce installation costs. The GEC has always been a pain in the neck. Best, August -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of John Berdner Sent: Monday, January 14, 2013 7:07 PM To: RE-wrenches Subject: Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules August: The WEEB or other Listed grounding means between the inverter case and the structure are not "contiguous or irreversible spliced" and therefore do not meet the requirements for a GEC. If the structure is then grounded via a bolt on lug it also is not irreversible or contiguous. If you can unbolt something and disconnect the ground then it is not contiguous or irreversibly spliced. Both of the above are ok for EGC but not for GEC. GEC is a pain in the neck but the Code requirements are clear. If the PV array conductor (pos or neg) is bonded to ground by the inverter then the inverter requires a GEC with all the related requirements - no if and's or but's. Best Regards, John Berdner General Manager, North America SolarEdge Technologies, Inc. 3347 Gateway Boulevard, Fremont CA 94538 USA (*Please note of our new address.) T: 510.498.3201 ext 747 M: 530.277.4894 -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of August Goers Sent: Monday, January 14, 2013 4:32 PM To: RE-wrenches Subject: Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules Hi Mark, There have been some recent threads on this list touching on this topic. As far as I understand, Enphase microinvertes still require a GEC up to and including the 2011 NEC. I don't know about the 2014 NEC. Enphase bonds the positive DC module conductor to ground. Pages 16 and 17 of their M215 installation manual address grounding: http://enphase.com/wp-uploads/enphase.com/2011/06/Enphase_M215_Installatio nOperation_Manual.pdf Products such as Solar Bridge that are listed as Alternating Current (AC) Modules (per NEC 690.2) don't need a Grounding Electrode Conductor (GEC) as long as there are no conductors connected to ground within the product. Solar Bridge has a good article on this: http://solarbridgetech.com/microinverters-and-ac-pv-modules-are-different/ This all takes us back to using Enphase with grounding washers like WEEBs for the GEC. According to what I read in their instructions (and after many phone calls), it sounds like they are okay with us running the GEC on the racking in #6 and then bonding the microinverters to the rack with WEEBs. Seems a little strange but it's been working for us. Good topic! Best, August 415.559.1525 -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Mark Frye Sent: Monday, January 14, 2013 3:31 PM To: RE-wrenches Subject: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules Does anyone have the latest on the GEC for micro-inverters/ACPV issue? I know it is still in NEC 2008 and I believe 2011 with plans to address it in 2014. I am specifically interested in the issue of GEC means continues (irreversible splices) and the whole business of the DC side of these devices constituting a separately derived system. Enphase technical support is fine if the micro inverter chasis is bonded to a EGC only, but they leav
Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules
Hi John, You have brought up several points. 1. practical answer The NEC says that a GEC can be solid aluminum. PV mounting rails are typically aluminum. It is easy to calculate the ampacity of a solid aluminum piece from its cross-section. Even the lightest rails on the market have an ampacity that is an order of magnitude greater than the copper wires required by code for GECs. The 2011 NEC, section 250.64(C)(3) says that "Bolted, riveted or welded connections of structural metal frames ... of structures" are permitted splices for the GEC. The WEEB is a tested and characterized device and therefore preferable to one that, while allowed by code, has not been characterized at all. 2. listing There is no standard to list equipment for use as a GEC or an EGC. The lack of a standard does not mean equipment is not suitable, it just means we need to use good engineering judgement until the codes catch up. Does new equipment meet the intent of the existing code? Are there any valid engineering reasons not to use new equipment? I think those are the questions we should focus on. Note that the WEEB was introduced almost 7 years ago and these code issues still have not been resolved to everyone's satisfaction. 3. connecting to a copper wire Jason Szumlanski discussed this already, but I will reiterate. When you connect a GEC to a string inverter it is done in a reversible manner, typical with a screw connection. When you connect to a PV system, consisting of multiple distributed inverters, you can do so with a reversible connection, typically a listed lug, anywhere on the PV system. Best Regards, Brian Wiley On 1/17/2013 10:58 AM, John Berdner wrote: Jay: You raise an interesting question. I believe the structure would have to be evaluated and Listed for equipment grounding (UL is working on a new Standard for this now) AND for use as a GEC (which I don't think is possible). Even if the WEEB was approved for use as a GEC (I still do not feel this is the case) the rail then needs to be contiguous or irreversibly spliced to the copper GEC. I am not aware of any Listed hardware that facilitates this. Anyone know of any ? We also have a dissimilar metals problem irreversibly crimping or exothermic welding (the Code requirement) copper to aluminum. Best Regards, John Berdner General Manager, North America Solaredge Technologies, Inc. 3347 Gateway Boulevard, Fremont CA 94538 USA */(*Please note of our new address.)/* T: 510.498.3201 ext 747 M: 530.277.4894 *From:*re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] *On Behalf Of *jay peltz *Sent:* Wednesday, January 16, 2013 8:52 PM *To:* RE-wrenches *Subject:* Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules Dear John and Brian Thanks for a great discussion. My question is: If you used a WEEB to connect the inverter to the rail, is the rack rail listed as a GEC? Or does it have to be listed as a GEC? Thanks Jay Peltz power Sent from my iPad On Jan 16, 2013, at 12:09 PM, Brian Wiley <mailto:btwinfin...@gmail.com>> wrote: Hi John, I don't feel that you are argumentative. I am glad for this forum and people to put forth honest opinions. I think you just may not be aware of how the WEEB actually works. It is a type of rivet, not just a pronged thing that makes connection as part of a bolted connection. It does use a bolt to engage the part, but the teeth on the WEEB are specially shaped. When the bolt is torqued, the teeth deform, similarly to a rivet. The metal that it is connecting to mushrooms up around the tooth and the tooth pinches in around the metal. This deforming action is what forms an exceptional electrical connection and also forms an air-tight seal between the part and embedded metal to resist corrosion. If you remove the bolt, the WEEB will still be connected to the metal. You must forcibly remove the WEEB from the metal. Hope that clears things up for you. Best Regards, Brian Wiley CONFIDENTIALITY NOTICE: This e-mail and its attachments are intended only for the use of the individual or entity who is the intended recipient and may contain information that is privileged, confidential and exempt from disclosure or any type of use under applicable law. If the reader of this e-mail is not the intended recipient, or the employee, agent, or representative responsible for delivering the e-mail to the intended recipient, you are hereby notified that any dissemination, distribution, copying, or other use of this e-mail is strictly prohibited. If you have received this e-mail in error, please reply immediately to the sender. *P* Please think of the environment before printing this email ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wren
Re: [RE-wrenches] [Fwd: Re: ice accumulation]
Hi Bob, I have tried this experiment on Sharp 175s. I backfed them at their rated current, but never got any heating effect. Not sure why it didn't work. Best Regards, Brian Wiley Wiley Electronics LLC boB wrote: I was discussing this off-line with Ron (Copied below). I cc'd here but I didn't quite "have it right" yet for this new list site, so this is also a test... He's using HIT 195 modules which, ~might~ just turn out to be ~700 Watt heating elements. I've never tried applying this much power to a module, but it could theoretically work. (?) The 700 Watt (approximate) figure comes from Voc times 66% (10 Amps) Series Fuse current Rating for these modules. I see that the rating is 15 Amps. You could go higher in forward current but this seems like a decent limit cuz you don't want to trip the breaker. I'd love to know if this actually works at melting snow and ice. What you use for this exactly, I'm not sure Maybe a "Defrost " mode in some future MPPT charge controller ?? BTW, Rainex doesn't seem to keep the snow from sticking on my parked car windshield here, but the windshield isn't vertical either. boB On Aug 14, 2008, at 5:53 PM, Bob Gudgel wrote: Hi Ron... What a beautiful comm site and breath-taking view !! (maybe one could ski back to town?) If there were enough extra energy storage, I would try, somehow, driving the PV modules just above their Voc (treating them like forward biased diodes), and see if that would make enough heat so that the ice would melt on the panels. This is something I have long wanted to try, but just don't have a mountaintop system to test on. <> boB K7IQ Disclaimer: I make no guarrantees on anything using this method. On Thu, 14 Aug 2008, Ron Young wrote: Hi Wrenches, I know this is a nice cool subject for these (hopefully) sun filled days. I am working on a telecom system that has some issues with ice <> Ron earthRight Solar ___ List sponsored by Home Power magazine RE-wrenches@lists.re-wrenches.org http://lists.re-wrenches.org/listinfo.cgi/re-wrenches-re-wrenches.org List rules & etiquette: http://www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.138 / Virus Database: 270.6.3/1613 - Release Date: 8/15/2008 5:58 AM ___ List sponsored by Home Power magazine RE-wrenches@lists.re-wrenches.org http://lists.re-wrenches.org/listinfo.cgi/re-wrenches-re-wrenches.org List rules & etiquette: http://www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Module grounding requirements
Hi Jim. Please see http://we-llc.com/WEEBLug_story.html. You can certainly repeat the test in your own lab. What we were trying to point out is that the contact area for 2 threads of a thread forming screw do not match the rating of the lug. The lug does meet the UL467 standard, but the lug plus thread forming screw does not. Best Regards, Brian Wiley North Texas Renewable Energy Inc wrote: 6) I think John Wiles recommended the star washer / bolt / weather resistant lug combination as a solution in the absence of a module manufacture's specific instructions. Dick Ratico Solarwind Electric Bradford, VT After a quick search of Brian Wileys www site we-llc, I could not find the video clip that allegedly shows the traditional burial-rated ground lug frying its mounting screw at its rated ampacity. Has this controversy been cleared up or just vanished due to lack of interest? Jim Duncan North Texas Renewable Energy Inc 817.917.0527 nt...@earthlink.net www.ntrei.com ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.176 / Virus Database: 270.10.4/1880 - Release Date: 1/7/2009 8:49 AM begin:vcard fn:Brian Wiley n:Wiley;Brian org:Wiley Electronics LLC adr;dom:;;44 Peoples Road;Saugerties;NY;12477 email;internet:b...@we-llc.com title:President tel;work:845-247-2875 tel;fax:845-246-0189 x-mozilla-html:FALSE url:www.we-llc.com version:2.1 end:vcard ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
