Re: [RE-wrenches] Cable Tray Marking
1. In addition, there's a conflict of signal words for NEC 110.21(B) Field-Applied Hazard Markings."Where caution, warning, or danger signs or labels are required by this Code, the labels shall meet the following requirements ..." In other words, one signal word is DANGER and the other signal word is WARNING. Simply, DANGER *will* result in ... and WARNING *could* result in ... 2. Specifically, in NEC 2020 690.31(D)(2) the signal word of WARNING" was *removed* and does not now appear to conflict? In California, 2017 NEC/2019 CEC 690.31(G)(3) still has the WARNING signal word. By the way, NEC 392.18(H) refers to 110.21(B). BTW, more information ANSI Z535 is found here: https://webstore.ansi.org/standards/nema/ansiz5352011r2017-1668874 All the best, Martin Herzfeld, Interstate Renewable Energy Council (IREC) Certified Master Trainer ™ for Photovoltaics (PV) Installation Professional #IREC 10037 Contract Training Provider (CTP) Adjunct Professor, Energy - Since 2016 California Solar & Electrical Contractor License #00833782 C46, C10, D56, D31, C-7 - Since 2004 Solar, Electrical, Trenching, Pole Installation & Maintenance, Instrumentation Contract Solar (PV) Technical Inspector - 3rd Party Inspections Underwriters Laboratories (UL) Certified PV Installer #17, OSHA 30 OSHA-Authorized Construction Trainer #32-0105338 CompTIA Certified Technical Classroom Trainer (CTT+) #T3NSZCNBBKB4QTQG * Professional Member, International Association of Electrical Inspectors #7035507 - Since 2006 * Accredited and Registered North American Board of Certified Energy Practitioners (NABCEP) Continuing Education (CE) Training Provider On Thu, Sep 3, 2020, 5:53 AM Rebekah Hren wrote: > This is interesting, since the definition of high voltage was changed to > >1000V a few code cycles ago and it is somewhat consistently applied > throughout the NEC at that voltage (except for workspace clearances...er). > It seems this 392.18 label requirement could cause confusion and should be > changed to apply to >1000V circuits. However, the definition of high > voltage only applies with Article 490 , Equipment >1000V so the Article 392 > Cable Tray folks can do what they want in terms of where they require high > voltage labeling. I haven't done any research on the history of this > labeling requirement. > > > Corey maybe you would be willing to make a public input to change where > the label is required to >1000V circuits, thus there would be no > conflict with 690 since PV DC circuits in or on buildings cannot be >1000V. > Due Sept 10! > > 490.2 Definition. > > The definition in this section shall apply only within this article. > High Voltage. > > A potential difference of more than 1000 volts, nominal. > > Thanks for bringing this up Corey! > > > On Thu, Sep 3, 2020 at 12:36 AM Ray wrote: > >> This is interesting, because we were considering cable trays, too. My >> guess is that both requirements would apply. Picky, but I don't see that >> 690 exempts the requirements of 392. One is for PV, one is for over 600 v. >> Some code iteration in the future might have combined language for PV over >> 600 v " Danger - High Voltage Photovoltaic Source - Keep Away" and of >> course that's so verbose that the average Joe is just going to stick his >> paws in there anyway. >> >> Ray Walters >> Remote Solar >> 303 505-8760 >> >> On 9/2/20 7:54 PM, Corey Shalanski wrote: >> >> Wrenches, >> >> I am curious about the marking requirements for cable trays containing PV >> source/output circuits rated over 600 volts, installed on a building: >> >> >> NEC 392.18(H) requires a permanent, legible warning notice carrying the >> wording “DANGER — HIGH VOLTAGE — KEEP AWAY” at least once every 10 ft. >> >> NEC 690.31(G)(3) requires a label or marking with the wording "WARNING: >> PHOTOVOLTAIC POWER SOURCE" at least once every 10 ft. >> >> Does the 690.31 label take precedence? Are there any situations where >> both labels would be required (or recommended)? >> >> -- >> Corey Shalanski >> Jah Light Solar >> Portland, Jamaica >> >> ___ >> List sponsored by Redwood Alliance >> >> List Address: RE-wrenches@lists.re-wrenches.org >> >> Change listserver email address & >> 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 or update participant bios:www.members.re-wrenches.org >> >> ___ >> List sponsored by Redwood Alliance >> >> List Address: RE-wrenches@lists.re-wrenches.org >> >> Change listserver email address & 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
Re: [RE-wrenches] Cable Tray Marking
This is interesting, since the definition of high voltage was changed to >1000V a few code cycles ago and it is somewhat consistently applied throughout the NEC at that voltage (except for workspace clearances...er). It seems this 392.18 label requirement could cause confusion and should be changed to apply to >1000V circuits. However, the definition of high voltage only applies with Article 490 , Equipment >1000V so the Article 392 Cable Tray folks can do what they want in terms of where they require high voltage labeling. I haven't done any research on the history of this labeling requirement. Corey maybe you would be willing to make a public input to change where the label is required to >1000V circuits, thus there would be no conflict with 690 since PV DC circuits in or on buildings cannot be >1000V. Due Sept 10! 490.2 Definition. The definition in this section shall apply only within this article. High Voltage. A potential difference of more than 1000 volts, nominal. Thanks for bringing this up Corey! On Thu, Sep 3, 2020 at 12:36 AM Ray wrote: > This is interesting, because we were considering cable trays, too. My > guess is that both requirements would apply. Picky, but I don't see that > 690 exempts the requirements of 392. One is for PV, one is for over 600 v. > Some code iteration in the future might have combined language for PV over > 600 v " Danger - High Voltage Photovoltaic Source - Keep Away" and of > course that's so verbose that the average Joe is just going to stick his > paws in there anyway. > > Ray Walters > Remote Solar > 303 505-8760 > > On 9/2/20 7:54 PM, Corey Shalanski wrote: > > Wrenches, > > I am curious about the marking requirements for cable trays containing PV > source/output circuits rated over 600 volts, installed on a building: > > > NEC 392.18(H) requires a permanent, legible warning notice carrying the > wording “DANGER — HIGH VOLTAGE — KEEP AWAY” at least once every 10 ft. > > NEC 690.31(G)(3) requires a label or marking with the wording "WARNING: > PHOTOVOLTAIC POWER SOURCE" at least once every 10 ft. > > Does the 690.31 label take precedence? Are there any situations where both > labels would be required (or recommended)? > > -- > Corey Shalanski > Jah Light Solar > Portland, Jamaica > > ___ > List sponsored by Redwood Alliance > > List Address: RE-wrenches@lists.re-wrenches.org > > Change listserver email address & > 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 or update participant bios:www.members.re-wrenches.org > > ___ > List sponsored by Redwood Alliance > > List Address: RE-wrenches@lists.re-wrenches.org > > Change listserver email address & 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 or update participant bios: > www.members.re-wrenches.org > > ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address & 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 or update participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Cable Tray Marking
This is interesting, because we were considering cable trays, too. My guess is that both requirements would apply. Picky, but I don't see that 690 exempts the requirements of 392. One is for PV, one is for over 600 v. Some code iteration in the future might have combined language for PV over 600 v " Danger - High Voltage Photovoltaic Source - Keep Away" and of course that's so verbose that the average Joe is just going to stick his paws in there anyway. Ray Walters Remote Solar 303 505-8760 On 9/2/20 7:54 PM, Corey Shalanski wrote: Wrenches, I am curious about the marking requirements for cable trays containing PV source/output circuits rated over 600 volts, installed on a building: NEC 392.18(H) requires a permanent, legible warning notice carrying the wording “DANGER — HIGH VOLTAGE — KEEP AWAY” at least once every 10 ft. NEC 690.31(G)(3) requires a label or marking with the wording "WARNING: PHOTOVOLTAIC POWER SOURCE" at least once every 10 ft. Does the 690.31 label take precedence? Are there any situations where both labels would be required (or recommended)? -- Corey Shalanski Jah Light Solar Portland, Jamaica ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address & 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 or update participant bios: www.members.re-wrenches.org ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address & 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 or update participant bios: www.members.re-wrenches.org
[RE-wrenches] Cable Tray Marking
Wrenches, I am curious about the marking requirements for cable trays containing PV source/output circuits rated over 600 volts, installed on a building: NEC 392.18(H) requires a permanent, legible warning notice carrying the wording “DANGER — HIGH VOLTAGE — KEEP AWAY” at least once every 10 ft. NEC 690.31(G)(3) requires a label or marking with the wording "WARNING: PHOTOVOLTAIC POWER SOURCE" at least once every 10 ft. Does the 690.31 label take precedence? Are there any situations where both labels would be required (or recommended)? -- Corey Shalanski Jah Light Solar Portland, Jamaica ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address & 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 or update participant bios: www.members.re-wrenches.org
[RE-wrenches] Cable tray
Hello wrenches, question about running conductors in cable tray. So we have our allowance in 690.31(C)(2) for using small PV Wire in cable tray for PV source and output circuits. I'm trying to determine what adjustment factor to apply when there are a bunch of small conductors. 392.80(A)(2)(a) and (b) both address single conductor cable in covered cable tray, but only refer to conductors from 1/0 to 500 kcmil, and 600 kcmil and up. I'm looking more at 40 or 50 12 AWG conductors (20 to 30 source circuits). The adjustment factors in 392.80(A)(2) are pretty hefty - only 60 to 70% of the rated ampacity, but as stated in Table 301.15(B)(17) (conductors in free air, so that helps). Any guidance would be much appreciated, and thanks for your time, Brian Mehalic NABCEP Certified Solar PV Installation Professional™ R031508-59 PV Curriculum Developer and Instructor Solar Energy International http://www.solarenergy.org ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Cable tray
Brian, I don’t know that I have a lot of good news for you. I have looked into this and I really don’t see a good way out of making some pretty conservative assumptions. You can read what I wrote in my IAEI article on Support of Exposed Cable earlier this year. I get into ampacity briefly though it is not the focus of the article. http://iaeimagazine.org/magazine/2015/04/14/support-of-exposed-cable-for-pv-systems-requirements-and-recommendations/ Bundling 50-60 conductor together should have a much worse impact than working off the free-air table. I believe the only way to evaluate that bundle is to treat it as if it is in a raceway. The lesser number of conductors (bundle of 3 or 4), the more it will begin to act like a free air cable. Bill. From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Brian Mehalic Sent: Monday, August 31, 2015 2:56 PM To: RE-wrenches <re-wrenches@lists.re-wrenches.org> Subject: [RE-wrenches] Cable tray Hello wrenches, question about running conductors in cable tray. So we have our allowance in 690.31(C)(2) for using small PV Wire in cable tray for PV source and output circuits. I'm trying to determine what adjustment factor to apply when there are a bunch of small conductors. 392.80(A)(2)(a) and (b) both address single conductor cable in covered cable tray, but only refer to conductors from 1/0 to 500 kcmil, and 600 kcmil and up. I'm looking more at 40 or 50 12 AWG conductors (20 to 30 source circuits). The adjustment factors in 392.80(A)(2) are pretty hefty - only 60 to 70% of the rated ampacity, but as stated in Table 301.15(B)(17) (conductors in free air, so that helps). Any guidance would be much appreciated, and thanks for your time, Brian Mehalic NABCEP Certified Solar PV Installation Professional™ R031508-59 PV Curriculum Developer and Instructor Solar Energy International http://www.solarenergy.org --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Cable tray
be considered. That goes without saying. Whether higher voltage is a win or not depends on the system. It may be in some cases, and not in others. Chris mentioned only specific aspects of the BOS hardware -- which I addressed. Regards to all, Dan Lepinski Sr. Engineer Exeltech / Exeltech Solar Products --- On *Sun, 3/31/13, John Berdner john.berd...@solaredge.com* wrote: From: John Berdner john.berd...@solaredge.com Subject: Re: [RE-wrenches] Cable tray To: RE-wrenches re-wrenches@lists.re-wrenches.org Date: Sunday, March 31, 2013, 1:08 PM Dan: I have to disagree with your statement regarding costs and voltage. While clearance and creepage distances increase at 1000V this makes only some things larger. Example: The control electronics and all ac output circuitry remain the same. Although the spacing between the high voltage dc components increases, the power of the device also increases and the losses decrease. The result is that the product might be a little larger but its power rating will be higher and it will likely be more efficient. For a given current level the higher voltage might increase the unit price slightly but the $/Watt will almost certainly decrease. Conversely if power is held constant the current will be lower and so the product may in fact be cheaper that a 600V product of the same power rating. Once we get past the unit price for components there is no doubt that system costs for 1000V are significantly lower than for 600V. Let’s review… Ohms law: P=V*I, so for a given power level voltage and current are inversely linked linearly – if the voltage increases the current decreases. P=I^2 * R, so for a given power level, increasing the voltage decreases the current and decreases the losses by square of the change. 1000/600 = 1.667 = P_loss= 1.6667^2, so for a given power level and given piece of wire, the losses are 2.777 times lower at 1000V than at 600V. Wire and Ampacity: The ampacity of a wire is based on current not voltage Higher voltages mean 1.667 times more power on a given piece of wire in a given conduit (yes the conduit might need to be bigger due to fill factor – it depends). Another way of saying this is 1000 Vdc gives you a 40% reduction in wiring costs for a given power level compared to 600Vdc. Small gauge PV wire is already available from multiple sources with 1000 and 2000 V ratings for a small premium over 600 V wire. Why ? - Current = conductive materials = expensive. Voltage = insulating materials = inexpensive. Larger gauge PV wire and USE-2 is still a bit hard to find but are both available in commonly used PV sizes from multiple sources Fuses and Combiners: kW per string is a key cost metric for installed BOS costs and more is better. Fundamentally, series trumps parallel every time. Higher voltages = longer strings = more power per string = less strings, fuses and holders (combiner inputs). 1000 V string fuses / holders are available from multiple sources and are competitive with 600V counterparts. Switches: 1000V switchgear cost is still lagging in the US but we are starting to see more reasonably priced equipment on the horizon. Summary: 1000V PV is well proven outside the US. In the US the tide is turning and we are rapidly headed to 1000V commercial systems. The Codes and Standards are already in place and we are beginning to see reasonably priced 1000 Vdc rated components. 1000Vdc Listed Modules, 1000/2000Vdc UL 4703 PV wire, Listed 1000Vdc string fuses and holders, Listed 1000Vdc inverters are all available today. I believe 600Vdc commercial and utility scale systems will rapidly become uncompetitive and, within a few years, the exception rather than the rule. Best Regards, John Berdner General Manager, North America SolarEdge Technologies, Inc. *From:* re-wrenches-boun...@lists.re-wrenches.org [mailto: re-wrenches-boun...@lists.re-wrenches.org] *On Behalf Of *Exeltech *Sent:* Sunday, March 31, 2013 9:10 AM *To:* RE-wrenches *Subject:* Re: [RE-wrenches] Cable tray Hello Chris, From a manufacturer's perspective .. you're incorrect on all assumptions. (Sorry.) It costs more to make higher-voltage anythings. Higher voltage means: Clearance / creepage distances are larger (thus bigger parts or products). Insulation must be thicker (or have a higher dielectric rating). This results in more rigorous (consequently more expensive) UL testing. Etc. All adds up. Dan --- On *Sun, 3/31/13, Chris Mason cometenergysyst...@gmail.comhttp://mc/compose?to=cometenergysyst...@gmail.com * wrote: From: Chris Mason cometenergysyst...@gmail.comhttp://mc/compose?to=cometenergysyst...@gmail.com Subject: Re: [RE-wrenches] Cable tray To: RE-wrenches re-wrenches@lists.re-wrenches.orghttp://mc/compose?to=re-wrenches@lists.re-wrenches.org Date: Sunday, March 31, 2013, 8:21 AM As we see
Re: [RE-wrenches] Cable tray
Conductors rated for 1000V and the same power you have in mind for the 600V conductors (hence lower current) can indeed use smaller wire, thus potentially saving on that aspect of the cost, and possibly making it lower in cost for a given system than the lower-voltage higher current counterpart. If the European hardware you bought is fully certified to the required UL Standards for use in the USA, then product size is simply a matter of design differences. Could also be product volume since they are way ahead of us in the 1000V category. Issues we as manufacturers in America face when trying to compete with firms in other countries are: 1) numerous additional costs related to things like Workman's Comp insurance, social security (for every dollar you have withheld, the employer matches it), now mandatory health insurance for some (depending on company size), and so forth. 2) Strict environmental regulations that foreign companies may or may not have. Even if they DO, we often find enforcement of those rules to be very lax, especially in Asia. 3) Cost of living, thus higher wages in the USA. .. to name a few. Ends up being higher-cost products. Dan --- On Mon, 4/1/13, Chris Mason cometenergysyst...@gmail.com wrote: From: Chris Mason cometenergysyst...@gmail.com Subject: Re: [RE-wrenches] Cable tray To: RE-wrenches re-wrenches@lists.re-wrenches.org Date: Monday, April 1, 2013, 9:23 AM With regards to 600V costs Vs 1000V costs, once 1000V equipment becomes the norm, it is likely not to cost appreciably more, and the lower cost of copper will offset any increase. I bought 1000V SolarBos combiners which are huge, too big to use on my installation, so I bought the same item from the UK, which are tiny and easy to install, and half the cost. Something is wrong with the US approach to 100V equipment and switchgear in general. Why is the european equipment so much smaller for the same switching current. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
Actually the operational cost in the UK is higher. They have had health insurance for some time, the US did not invent it. Taxes are higher, in fact the US has one of the lowest tax rates in the OECD. Once the US moves to 1000V there will be little cost difference, I am pretty certain of that. On Mon, Apr 1, 2013 at 11:32 AM, Exeltech exelt...@yahoo.com wrote: Conductors rated for 1000V and the same power you have in mind for the 600V conductors (hence lower current) can indeed use smaller wire, thus potentially saving on that aspect of the cost, and possibly making it lower in cost for a given system than the lower-voltage higher current counterpart. If the European hardware you bought is fully certified to the required UL Standards for use in the USA, then product size is simply a matter of design differences. Could also be product volume since they are way ahead of us in the 1000V category. Issues we as manufacturers in America face when trying to compete with firms in other countries are: 1) numerous additional costs related to things like Workman's Comp insurance, social security (for every dollar you have withheld, the employer matches it), now mandatory health insurance for some (depending on company size), and so forth. 2) Strict environmental regulations that foreign companies may or may not have. Even if they DO, we often find enforcement of those rules to be very lax, especially in Asia. 3) Cost of living, thus higher wages in the USA. .. to name a few. Ends up being higher-cost products. Dan --- On *Mon, 4/1/13, Chris Mason cometenergysyst...@gmail.com* wrote: From: Chris Mason cometenergysyst...@gmail.com Subject: Re: [RE-wrenches] Cable tray To: RE-wrenches re-wrenches@lists.re-wrenches.org Date: Monday, April 1, 2013, 9:23 AM With regards to 600V costs Vs 1000V costs, once 1000V equipment becomes the norm, it is likely not to cost appreciably more, and the lower cost of copper will offset any increase. I bought 1000V SolarBos combiners which are huge, too big to use on my installation, so I bought the same item from the UK, which are tiny and easy to install, and half the cost. Something is wrong with the US approach to 100V equipment and switchgear in general. Why is the european equipment so much smaller for the same switching current. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 -- Chris Mason President, Comet Systems Ltd www.cometenergysystems.com Cell: 264.235.5670 Skype: netconcepts ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
On 4/1/2013 9:37 AM, Chris Mason wrote: Actually the operational cost in the UK is higher. They have had health insurance for some time, the US did not invent it. Taxes are higher, in fact the US has one of the lowest tax rates in the OECD. Once the US moves to 1000V there will be little cost difference, I am pretty certain of that. 1000V is definitely coming and we are trying to keep costs as low as possible. And, before this has to go to another group that I can't post to, I have to agree with most of what Dan says about operating in the US. It is looking like it is only going to get worse to manufacture in the US. I hope we can keep the made in the USA label keep coming. A lot of made in USA equipment is already only a final assembly and not a significant portion of the products manufacture. For example, circuit board assembly in China and then put the rest together here. It's not always what the restrictions are, (example: health care, taxes), but how those are implemented. I have heard of American companies moving to the northern UK Ireland or Scotland) because it was cheaper for them to operate there but might be because of some tax loophole ? I'm sure that hole will be plugged soon. We will do our best to keep our products significantly built in the USA. boB On Mon, Apr 1, 2013 at 11:32 AM, Exeltech exelt...@yahoo.com mailto:exelt...@yahoo.com wrote: Conductors rated for 1000V and the same power you have in mind for the 600V conductors (hence lower current) can indeed use smaller wire, thus potentially saving on that aspect of the cost, and possibly making it lower in cost for a given system than the lower-voltage higher current counterpart. If the European hardware you bought is fully certified to the required UL Standards for use in the USA, then product size is simply a matter of design differences. Could also be product volume since they are way ahead of us in the 1000V category. Issues we as manufacturers in America face when trying to compete with firms in other countries are: 1) numerous additional costs related to things like Workman's Comp insurance, social security (for every dollar you have withheld, the employer matches it), now mandatory health insurance for some (depending on company size), and so forth. 2) Strict environmental regulations that foreign companies may or may not have. Even if they DO, we often find enforcement of those rules to be very lax, especially in Asia. 3) Cost of living, thus higher wages in the USA. .. to name a few. Ends up being higher-cost products. Dan --- On *Mon, 4/1/13, Chris Mason /cometenergysyst...@gmail.com mailto:cometenergysyst...@gmail.com/* wrote: From: Chris Mason cometenergysyst...@gmail.com mailto:cometenergysyst...@gmail.com Subject: Re: [RE-wrenches] Cable tray To: RE-wrenches re-wrenches@lists.re-wrenches.org mailto:re-wrenches@lists.re-wrenches.org Date: Monday, April 1, 2013, 9:23 AM With regards to 600V costs Vs 1000V costs, once 1000V equipment becomes the norm, it is likely not to cost appreciably more, and the lower cost of copper will offset any increase. I bought 1000V SolarBos combiners which are huge, too big to use on my installation, so I bought the same item from the UK, which are tiny and easy to install, and half the cost. Something is wrong with the US approach to 100V equipment and switchgear in general. Why is the european equipment so much smaller for the same switching current. -- Chris Mason President, Comet Systems Ltd www.cometenergysystems.com http://www.cometenergysystems.com Cell: 264.235.5670 Skype: netconcepts ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
As we see more 1000V installations, chances are that 600V rated equipment will find its way into installations it is not rated for. To avoid problems and so we don't need two SKUs and lots more inventory, the manufacturers need to move all their product to 1000V ratings. I suspect it does not cost more to make 1000V wire than 600V, similarly disconnects, fuses, fuse holders and connectors. On Sat, Mar 30, 2013 at 9:57 PM, Jay Peltz j...@asis.com wrote: Hi Bill I'm with you all the way. I love to do things Telecomm style. Very clean, safe and better IMHO. 1000v PV wire can be bought at PV cables.com Cheers Jay Peltz Power. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 -- Chris Mason President, Comet Systems Ltd www.cometenergysystems.com Cell: 264.235.5670 Skype: netconcepts ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
Hello Chris, From a manufacturer's perspective .. you're incorrect on all assumptions. (Sorry.) It costs more to make higher-voltage anythings. Higher voltage means: Clearance / creepage distances are larger (thus bigger parts or products). Insulation must be thicker (or have a higher dielectric rating). This results in more rigorous (consequently more expensive) UL testing. Etc. All adds up. Dan --- On Sun, 3/31/13, Chris Mason cometenergysyst...@gmail.com wrote: From: Chris Mason cometenergysyst...@gmail.com Subject: Re: [RE-wrenches] Cable tray To: RE-wrenches re-wrenches@lists.re-wrenches.org Date: Sunday, March 31, 2013, 8:21 AM As we see more 1000V installations, chances are that 600V rated equipment will find its way into installations it is not rated for. To avoid problems and so we don't need two SKUs and lots more inventory, the manufacturers need to move all their product to 1000V ratings. I suspect it does not cost more to make 1000V wire than 600V, similarly disconnects, fuses, fuse holders and connectors. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
I have to agree with Dan. Making disconnects that can open 1000vdc under load as compared to 600vdc under load will be far more pricey. To Rate all gear for 1000vdc will be prohibitive. Ryan Ryan Stankevitz Technical Support Manager MidNite Solar Inc. r...@midnitesolar.com 360-403-7207 XT 151 Skype ID ryan.midnite On 3/31/2013 12:09 PM, Exeltech wrote: Hello Chris, From a manufacturer's perspective .. you're incorrect on all assumptions. (Sorry.) It costs more to make higher-voltage anythings. Higher voltage means: Clearance / creepage distances are larger (thus bigger parts or products). Insulation must be thicker (or have a higher dielectric rating). This results in more rigorous (consequently more expensive) UL testing. Etc. All adds up. Dan --- On *Sun, 3/31/13, Chris Mason /cometenergysyst...@gmail.com/* wrote: From: Chris Mason cometenergysyst...@gmail.com Subject: Re: [RE-wrenches] Cable tray To: RE-wrenches re-wrenches@lists.re-wrenches.org Date: Sunday, March 31, 2013, 8:21 AM As we see more 1000V installations, chances are that 600V rated equipment will find its way into installations it is not rated for. To avoid problems and so we don't need two SKUs and lots more inventory, the manufacturers need to move all their product to 1000V ratings. I suspect it does not cost more to make 1000V wire than 600V, similarly disconnects, fuses, fuse holders and connectors. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
Dan: I have to disagree with your statement regarding costs and voltage. While clearance and creepage distances increase at 1000V this makes only some things larger. Example: The control electronics and all ac output circuitry remain the same. Although the spacing between the high voltage dc components increases, the power of the device also increases and the losses decrease. The result is that the product might be a little larger but its power rating will be higher and it will likely be more efficient. For a given current level the higher voltage might increase the unit price slightly but the $/Watt will almost certainly decrease. Conversely if power is held constant the current will be lower and so the product may in fact be cheaper that a 600V product of the same power rating. Once we get past the unit price for components there is no doubt that system costs for 1000V are significantly lower than for 600V. Let's review... Ohms law: P=V*I, so for a given power level voltage and current are inversely linked linearly - if the voltage increases the current decreases. P=I^2 * R, so for a given power level, increasing the voltage decreases the current and decreases the losses by square of the change. 1000/600 = 1.667 = P_loss= 1.6667^2, so for a given power level and given piece of wire, the losses are 2.777 times lower at 1000V than at 600V. Wire and Ampacity: The ampacity of a wire is based on current not voltage Higher voltages mean 1.667 times more power on a given piece of wire in a given conduit (yes the conduit might need to be bigger due to fill factor - it depends). Another way of saying this is 1000 Vdc gives you a 40% reduction in wiring costs for a given power level compared to 600Vdc. Small gauge PV wire is already available from multiple sources with 1000 and 2000 V ratings for a small premium over 600 V wire. Why ? - Current = conductive materials = expensive. Voltage = insulating materials = inexpensive. Larger gauge PV wire and USE-2 is still a bit hard to find but are both available in commonly used PV sizes from multiple sources Fuses and Combiners: kW per string is a key cost metric for installed BOS costs and more is better. Fundamentally, series trumps parallel every time. Higher voltages = longer strings = more power per string = less strings, fuses and holders (combiner inputs). 1000 V string fuses / holders are available from multiple sources and are competitive with 600V counterparts. Switches: 1000V switchgear cost is still lagging in the US but we are starting to see more reasonably priced equipment on the horizon. Summary: 1000V PV is well proven outside the US. In the US the tide is turning and we are rapidly headed to 1000V commercial systems. The Codes and Standards are already in place and we are beginning to see reasonably priced 1000 Vdc rated components. 1000Vdc Listed Modules, 1000/2000Vdc UL 4703 PV wire, Listed 1000Vdc string fuses and holders, Listed 1000Vdc inverters are all available today. I believe 600Vdc commercial and utility scale systems will rapidly become uncompetitive and, within a few years, the exception rather than the rule. 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: 510.498.3200, X 747 M: 530.277.4894 From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Exeltech Sent: Sunday, March 31, 2013 9:10 AM To: RE-wrenches Subject: Re: [RE-wrenches] Cable tray Hello Chris, From a manufacturer's perspective .. you're incorrect on all assumptions. (Sorry.) It costs more to make higher-voltage anythings. Higher voltage means: Clearance / creepage distances are larger (thus bigger parts or products). Insulation must be thicker (or have a higher dielectric rating). This results in more rigorous (consequently more expensive) UL testing. Etc. All adds up. Dan --- On Sun, 3/31/13, Chris Mason cometenergysyst...@gmail.commailto:cometenergysyst...@gmail.com wrote: From: Chris Mason cometenergysyst...@gmail.commailto:cometenergysyst...@gmail.com Subject: Re: [RE-wrenches] Cable tray To: RE-wrenches re-wrenches@lists.re-wrenches.orgmailto:re-wrenches@lists.re-wrenches.org Date: Sunday, March 31, 2013, 8:21 AM As we see more 1000V installations, chances are that 600V rated equipment will find its way into installations it is not rated for. To avoid problems and so we don't need two SKUs and lots more inventory, the manufacturers need to move all their product to 1000V ratings. I suspect it does not cost more to make 1000V wire than 600V, similarly disconnects, fuses, fuse holders and connectors. 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
Re: [RE-wrenches] Cable tray
And yet, in Europe, it is. On Sun, Mar 31, 2013 at 2:49 PM, Ryan r...@kb1uas.com wrote: I have to agree with Dan. Making disconnects that can open 1000vdc under load as compared to 600vdc under load will be far more pricey. To Rate all gear for 1000vdc will be prohibitive. Ryan Ryan Stankevitz Technical Support Manager MidNite Solar Inc.ryan@midnitesolar.com360-403-7207 XT 151 Skype ID ryan.midnite On 3/31/2013 12:09 PM, Exeltech wrote: Hello Chris, From a manufacturer's perspective .. you're incorrect on all assumptions. (Sorry.) It costs more to make higher-voltage anythings. Higher voltage means: Clearance / creepage distances are larger (thus bigger parts or products). Insulation must be thicker (or have a higher dielectric rating). This results in more rigorous (consequently more expensive) UL testing. Etc. All adds up. Dan --- On *Sun, 3/31/13, Chris Mason cometenergysyst...@gmail.comcometenergysyst...@gmail.com * wrote: From: Chris Mason cometenergysyst...@gmail.comcometenergysyst...@gmail.com Subject: Re: [RE-wrenches] Cable tray To: RE-wrenches re-wrenches@lists.re-wrenches.orgre-wrenches@lists.re-wrenches.org Date: Sunday, March 31, 2013, 8:21 AM As we see more 1000V installations, chances are that 600V rated equipment will find its way into installations it is not rated for. To avoid problems and so we don't need two SKUs and lots more inventory, the manufacturers need to move all their product to 1000V ratings. I suspect it does not cost more to make 1000V wire than 600V, similarly disconnects, fuses, fuse holders and connectors. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 -- Chris Mason President, Comet Systems Ltd www.cometenergysystems.com Cell: 264.235.5670 Skype: netconcepts ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
John, My reply didn't deal with anything except specific hardware (per Chris' mention in his original post), his musings that he suspects it does not cost more to make that leap, and the actual impact on cost for migrating that hardware from 600Vdc to 1000Vdc. Nothing was mentioned either by Chris or by me related to control electronics, power ratings, or power loss. To Chris' statement: BEGIN QUOTE: I suspect it does not cost more to make 1000V wire than 600V, similarly disconnects, fuses, fuse holders and connectors. END QUOTE. All things being equal: 1000V wire in the same gauge as 600V wire will be more expensive than the 600V wire. If you wish to downsize the conductor, the cost of the metal is likely more expensive than the insulation, and this is a potential win .. but conductor size wasn't mentioned. 1000V disconnects for a given current are going to be more expensive than 600V disconnects. 1000V rated fuses are going to be more expensive than 600V for a given current. 1000V fuse holders require larger spacings than 600V, so they too are more money. 1000V connectors require larger creepage and clearances than do 600V parts. This means they're larger for a given number of contacts and current, thus more $$$ -- even if just slightly more. Still more. This is not to say migrating to 1000V won't happen. It will, and it is. Yes, it's more common in Europe. Sometimes the USA doesn't lead, but follows. This is one of those instances. And to your point: John Berdner Wrote: Although the spacing between the high voltage dc components increases, the power of the device also increases and the losses decrease. Referencing I^2 R loss .. yes. Passive resistive devices at a higher voltage and lower current do have less loss than their lower-voltage cousins, (again, all things being equal, but that doesn't mean they're less expensive than their lower-voltage counterpart. It's simply not possible to make a blanket statement and have it cover everything correctly. And to your additional point: Small gauge PV wire is already available from multiple sources with 1000 and 2000 V ratings for a small premium over 600 V wire. ... for a small premium over 600V wire. You admit the wire is more expensive (even if at present). Still, it's more $. Will it stay that way? Likely not, but for NOW .. it's more expensive. Now then .. taking your comment in context: BEGIN QUOTE: Example: The control electronics and all ac output circuitry remain the same. Although the spacing between the high voltage dc components increases, the power of the device also increases and the losses decrease. The result is that the product might be a little larger but its power rating will be higher and it will likely be more efficient. This infers reference to the efficiency of switching electronics. If so, your statement is incorrect. Let's consider the solid state switches in an inverter, whether they be MOSFETs, IGBTs, GaN, etc. With the devices presently on the market, switching loss goes UP as the voltage increases. This will likely change at some future point with new product discoveries, but for now .. given the parts we have to work with, switching losses are greater in the higher voltage parts. I know this flies in the face of common sense to non-engineers, but it's fact. If you wish an alternate resource of verification on this, I suggest you check with anyone else with considerable expertise in the design of switchmode power supplies. If my 41 years as a design engineer isn't adequate here, boB and/or Robin at at Midnight Solar would be an excellent starting point. I can point you toward a number of others who are equally qualified. Our industry (and even perhaps the Wrench board) has others as well. Ultimately .. will higher voltage systems be lower cost per watt overall? This remains to be seen. My instincts say it will --- in some circumstances. An advantage the increased voltage offers (beyond potentially less power loss in conductors), is the ability to create inverters for 277/480 and beyond. This helps by eliminating a transformer, which IS an efficiency loss and added cost element. Will 1000Vdc be a win for [say] 120V/240V installations. Likely not. As John did point out .. the entire system must be considered. That goes without saying. Whether higher voltage is a win or not depends on the system. It may be in some cases, and not in others. Chris mentioned only specific aspects of the BOS hardware -- which I addressed. Regards to all, Dan Lepinski Sr. Engineer Exeltech / Exeltech Solar Products --- On Sun, 3/31/13, John Berdner john.berd...@solaredge.com wrote: From: John Berdner john.berd...@solaredge.com Subject: Re: [RE-wrenches] Cable tray To: RE-wrenches re-wrenches@lists.re-wrenches.org Date: Sunday, March 31, 2013, 1:08 PM Dan: I have to disagree with your statement regarding costs and voltage.While clearance and creepage distances
Re: [RE-wrenches] Cable tray
Hi Bill I'm with you all the way. I love to do things Telecomm style. Very clean, safe and better IMHO. 1000v PV wire can be bought at PV cables.com Cheers Jay Peltz Power. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
Hi Chris, Thanks for a glimpse of how our German brethren handle PV design installation. After all, who has more experience with design, execution, and funding than the Germans? There remains an arrogance that the US has a lock on how best to do any number of things. Hopefully, this antiquated attitude will change, soon; hopefully, before we are all reduced to asking the equivalent of, Would you like to Supersize that meal? Best wishes on your install. Please keep us informed of how others around the world better handle these items. Bill Loesch Solar 1 - Saint Louis Solar On 28-Mar-13 1:03 PM, Chris Mason wrote: I am working on a large installation in a country that uses 230/400V 60Hz for the grid, so we had to look to Europe for the inverters and work 1000V. I spent some time on the phone with SMA Germany to discuss the reqiurements in Germany and to understand the design methodology the inverters were designed for. First of all, the inverters are gorgeous. The first one we installed is a 3Ph 17KW with 6 sets string inputs, 2 x MPPT. They connect the strings directly to the inverters, no disconnects. The inverters have a Electronic Solar Switch on the bottom, pull it down and the strings are disconnected. We are using 26 module strings or that install, which massively reduces cabling and components. I showed the engineer a photo of our larger installs, he laughed at the use of pipes for the cables. We install massive AC disconnects, they use a little isolator about the size of a Coke can. Everything is a multi-core cable. I also read a guide to the British Standards on PV installation, and their approach to grounding is absolutely different. Since PV conductors are all isolated now, they don't even want you to ground the array structures, in fact they describe grounding as a shock hazard. Very different mentality. I might think that the US way is likely safer if we were comparing with China or the third world, but this is Germany. I think they know electricity. Chris On Wed, Mar 27, 2013 at 12:16 PM, John Berdner john.berd...@solaredge.com mailto:john.berd...@solaredge.com wrote: Exposed single conductor sunlight resistant cable in cable trays are widely used in PV systems outside the US. There is a very large installed base of systems with good long term performance data using this type of construction. We should not discount the advantages of wire cable trays just because we are unfamiliar with it. Look at data cabling – Characterized by many, relatively small, cables over long distances with periodic drops. Sounds a lot like PV source circuits (other than voltage and current in the wires of course). There are lots of videos out there showing how to pull 10’s of pairs of wires simultaneously in cable trays. IMHO, we need to look at ideas like this to reduce installation cost and time. Installation costs are becoming the tall pole in the tent and new thinking is needed. As systems are falling to sub $3.00 /Watt all-in, running wire in conduit will simply not be cost effective. Running wire in conduit is one of the reasons PV installation costs in the US are double (or more) of those in Europe. As one of my former German colleagues noted: “It is only in the US where you need first to be a plumber before you can be an electrician” 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: 510.498.3200, X 747 tel:510.498.3200%2C%20X%20747 M: 530.277.4894 tel:530.277.4894 *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 *Allan Sindelar *Sent:* Wednesday, March 27, 2013 8:51 AM *To:* RE-wrenches *Subject:* Re: [RE-wrenches] Cable tray Andrew, We have used #10 USE-2 for about 16 years, and our high-elevation New Mexico sun is quite intense. I have yet to see any degradation exceeding fading discoloration on any conductors from that far back, even when directly exposed to sunlight. No cracking, peeling, delaminating, or hardening. Allan *Allan Sindelar* al...@positiveenergysolar.com mailto:al...@positiveenergysolar.com NABCEP Certified Photovoltaic Installer NABCEP Certified Technical Sales Professional New Mexico EE98J Journeyman Electrician Founder and Chief Technology Officer *Positive Energy, Inc.* 3209 Richards Lane (note new address) Santa Fe, New Mexico 87507 *505 424-1112 tel:505%20424-1112* www.positiveenergysolar.com http://www.positiveenergysolar.com/ On 3/27/2013 8:41 AM, Andrew Truitt wrote: Bill - What is your take
Re: [RE-wrenches] Cable tray
Technologies, Inc. 3347 Gateway Boulevard, Fremont CA 94538 USA *(*Please note of our new address.)* T: 510.498.3200, X 747 510.498.3200%2C%20X%20747 M: 530.277.4894 *From:* re-wrenches-boun...@lists.re-wrenches.org [mailto: re-wrenches-boun...@lists.re-wrenches.org] *On Behalf Of *Allan Sindelar *Sent:* Wednesday, March 27, 2013 8:51 AM *To:* RE-wrenches *Subject:* Re: [RE-wrenches] Cable tray Andrew, We have used #10 USE-2 for about 16 years, and our high-elevation New Mexico sun is quite intense. I have yet to see any degradation exceeding fading discoloration on any conductors from that far back, even when directly exposed to sunlight. No cracking, peeling, delaminating, or hardening. Allan *Allan Sindelar* al...@positiveenergysolar.com NABCEP Certified Photovoltaic Installer NABCEP Certified Technical Sales Professional New Mexico EE98J Journeyman Electrician Founder and Chief Technology Officer *Positive Energy, Inc.* 3209 Richards Lane (note new address) Santa Fe, New Mexico 87507 *505 424-1112 505%20424-1112* www.positiveenergysolar.com On 3/27/2013 8:41 AM, Andrew Truitt wrote: Bill - What is your take in conductor insulation degradation over time when exposed to UV? Regardless of the sunlight resistant labeling, USE-2 (and I assume PV wire though I haven't seen it yet) does show wear after years of exposure to direct sunlight. Maybe best practice would be to use cable trays where conductors are shaded and [properly installed] conduit when exposed to direct UV? - Andrew Truitt Sent from my iPad On Mar 26, 2013, at 11:55 PM, Bill Brooks billbroo...@yahoo.com wrote: William, I have all the respect in the world for you, but I’m not referring to “basket tray”, which is only appropriate for small conductors. I’m talking about legitimate cable tray that can be up to 12” wide and that has a top and rungs every 12”. The main facilities that use it in the United States are large industrial facilities. Most electricians don’t get to work with it. It is clearly superior to EMT and is at least as good as IMC without all the hassle of threaded fittings and setting up expansion joints and worrying about 20 years of conductors thermal cycling. Even the best electricians have problems with this stuff. I am talking about projects with 800 foot long feeder runs. We can bring them in the building and build a rack for the conduit or run covered tray outside. As the 2014 NEC will require, you will have to use contactor combiners or some other means to shut down the conductors inside a building. It’s all doable. My recommendation after seeing the aftermath of rooftop conduit by good electricians is to put cable tray on roofs and use conduit if you bring the feeders indoors. It will become common practice soon. Hopefully sooner than later. Bill. *From:* re-wrenches-boun...@lists.re-wrenches.org [ mailto:re-wrenches-boun...@lists.re-wrenches.orgre-wrenches-boun...@lists.re-wrenches.org] *On Behalf Of *William Miller *Sent:* Tuesday, March 26, 2013 9:49 PM *To:* RE-wrenches *Subject:* Re: [RE-wrenches] Cable tray Bill: I have to disagree with you on this one. We can not abandoned a tried and true practice just because some practitioners don't do it right. I don't know how one can justify saying that encapsulating high voltage conductors in a conduit is less safe than exposed in a flimsy basket. Consider snow and ice and falling objects. Too many installers entered the PV field without first acquiring the necessary skills as journeymen or women electricians. I don't see the benefit of rewriting the code to accommodate a lack of skills in the industry. Respectfully, William Miller PS: The temperature adders always encourage us to enter the building envelope at the first appropriate location to avoid adding them. Thoughtful installers will do the same. Wm At 10:15 PM 3/25/2013, you wrote: Content-Type: multipart/alternative; boundary==_NextPart_000_00E3_01CE29A6.37CC5110 Content-Language: en-us William, I would strongly disagree that conduit is tried and true on rooftops. I have rarely seen good conduit runs on rooftops. Most electricians have no clue how to work with expansion joints. Conduit on rooftops is a bad idea in general. Most conduit runs in big buildings are all done indoors for good reason. We are the crazy people doing things on the roof. The sooner we get away from conduitparticularly for long feeder runsthe better. In Europe they don’t have problems with their rooftop wiring systems because everything is in tray. For those that don’t allow cable tray for anything less than 1/0, just remember that if it isn’t called cable tray, then 392 doesn’t apply. The NEC would allow us to use treated lumber in place of cable tray. This makes no sense. We did some research on the origin of the 1/0 requirement, and it is ancient and no longer relevant. Just
Re: [RE-wrenches] Cable tray
I am working on a large installation in a country that uses 230/400V 60Hz for the grid, so we had to look to Europe for the inverters and work 1000V. I spent some time on the phone with SMA Germany to discuss the reqiurements in Germany and to understand the design methodology the inverters were designed for. First of all, the inverters are gorgeous. The first one we installed is a 3Ph 17KW with 6 sets string inputs, 2 x MPPT. They connect the strings directly to the inverters, no disconnects. The inverters have a Electronic Solar Switch on the bottom, pull it down and the strings are disconnected. We are using 26 module strings or that install, which massively reduces cabling and components. I showed the engineer a photo of our larger installs, he laughed at the use of pipes for the cables. We install massive AC disconnects, they use a little isolator about the size of a Coke can. Everything is a multi-core cable. I also read a guide to the British Standards on PV installation, and their approach to grounding is absolutely different. Since PV conductors are all isolated now, they don't even want you to ground the array structures, in fact they describe grounding as a shock hazard. Very different mentality. I might think that the US way is likely safer if we were comparing with China or the third world, but this is Germany. I think they know electricity. Chris On Wed, Mar 27, 2013 at 12:16 PM, John Berdner john.berd...@solaredge.comwrote: Exposed single conductor sunlight resistant cable in cable trays are widely used in PV systems outside the US. There is a very large installed base of systems with good long term performance data using this type of construction. We should not discount the advantages of wire cable trays just because we are unfamiliar with it. ** ** Look at data cabling – Characterized by many, relatively small, cables over long distances with periodic drops. Sounds a lot like PV source circuits (other than voltage and current in the wires of course). There are lots of videos out there showing how to pull 10’s of pairs of wires simultaneously in cable trays. IMHO, we need to look at ideas like this to reduce installation cost and time. ** ** Installation costs are becoming the tall pole in the tent and new thinking is needed. As systems are falling to sub $3.00 /Watt all-in, running wire in conduit will simply not be cost effective. Running wire in conduit is one of the reasons PV installation costs in the US are double (or more) of those in Europe. As one of my former German colleagues noted: “It is only in the US where you need first to be a plumber before you can be an electrician” ** ** 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: 510.498.3200, X 747 M: 530.277.4894 ** ** *From:* re-wrenches-boun...@lists.re-wrenches.org [mailto: re-wrenches-boun...@lists.re-wrenches.org] *On Behalf Of *Allan Sindelar *Sent:* Wednesday, March 27, 2013 8:51 AM *To:* RE-wrenches *Subject:* Re: [RE-wrenches] Cable tray ** ** Andrew, We have used #10 USE-2 for about 16 years, and our high-elevation New Mexico sun is quite intense. I have yet to see any degradation exceeding fading discoloration on any conductors from that far back, even when directly exposed to sunlight. No cracking, peeling, delaminating, or hardening. Allan *Allan Sindelar* al...@positiveenergysolar.com NABCEP Certified Photovoltaic Installer NABCEP Certified Technical Sales Professional New Mexico EE98J Journeyman Electrician Founder and Chief Technology Officer *Positive Energy, Inc.* 3209 Richards Lane (note new address) Santa Fe, New Mexico 87507 *505 424-1112* www.positiveenergysolar.com ** ** ** ** On 3/27/2013 8:41 AM, Andrew Truitt wrote: Bill - What is your take in conductor insulation degradation over time when exposed to UV? Regardless of the sunlight resistant labeling, USE-2 (and I assume PV wire though I haven't seen it yet) does show wear after years of exposure to direct sunlight. Maybe best practice would be to use cable trays where conductors are shaded and [properly installed] conduit when exposed to direct UV? ** ** - Andrew Truitt Sent from my iPad On Mar 26, 2013, at 11:55 PM, Bill Brooks billbroo...@yahoo.com wrote: William, I have all the respect in the world for you, but I’m not referring to “basket tray”, which is only appropriate for small conductors. I’m talking about legitimate cable tray that can be up to 12” wide and that has a top and rungs every 12”. The main facilities that use it in the United States are large industrial facilities. Most electricians don’t get to work with it. It is clearly superior to EMT
Re: [RE-wrenches] Cable tray
mall conductors. I’m
talking about legitimate cable tray that can be
up to 12” wide and that has a top and rungs
every 12”. The main facilities that use it in
the United States are large industrial
facilities. Most electricians don’t get to work
with it. It is clearly superior to EMT and is at
least as good as IMC without all the hassle of
threaded fittings and setting up expansion
joints and worrying about 20 years of conductors
thermal cycling. Even the best electricians have
problems with this stuff.
I
am talking about projects with 800 foot long
feeder runs. We can bring them in the building
and build a rack for the conduit or run covered
tray outside. As the 2014 NEC will require, you
will have to use contactor combiners or some
other means to shut down the conductors inside a
building. It’s all doable. My recommendation
after seeing the aftermath of rooftop conduit by
good electricians is to put cable tray on roofs
and use conduit if you bring the feeders
indoors. It will become common practice soon.
Hopefully sooner than later.
Bill.
From:
re-wrenches-boun...@lists.re-wrenches.org
[mailto:re-wrenches-boun...@lists.re-wrenches.org]
On Behalf Of William Miller
Sent: Tuesday, March 26, 2013 9:49 PM
To: RE-wrenches
Subject: Re: [RE-wrenches] Cable tray
Bill:
I have to disagree with you on this one. We can
not abandoned a tried and true practice just
because some practitioners don't do it right. I
don't know how one can justify saying that
encapsulating high voltage conductors in a conduit
is less safe than exposed in a flimsy basket.
Consider snow and ice and falling objects.
Too many installers entered the PV field without
first acquiring the necessary skills as journeymen
or women electricians. I don't see the benefit of
rewriting the code to accommodate a lack of skills
in the industry.
Respectfully,
William Miller
PS: The temperature adders always encourage us to
enter the building envelope at the first
appropriate location to avoid adding them.
Thoughtful installers will do the same.
Wm
At 10:15 PM 3/25/2013, you wrote:
Content-Type:
multipart/alternative;
boundary="=_NextPart_000_00E3_01CE29A6.37CC5110"
Content-Language: en-us
William,
I would strongly disagree that conduit is tried
and true on rooftops. I have rarely seen good
conduit runs on rooftops. Most electricians have
no clue how to work with expansion joints. Conduit
on rooftops is a bad idea in general. Most conduit
runs in big buildings are all done indoors for
good reason. We are the crazy people doing things
on the roof.
The sooner we get away from conduitparticularly
for long feeder runsthe better.
In Europe they don’t have problems with their
rooftop wiring systems because everything is in
tray.
For those that don’t allow cable tray for anything
less than 1/0,
Re: [RE-wrenches] Cable tray
Bill - What is your take in conductor insulation degradation over time when exposed to UV? Regardless of the sunlight resistant labeling, USE-2 (and I assume PV wire though I haven't seen it yet) does show wear after years of exposure to direct sunlight. Maybe best practice would be to use cable trays where conductors are shaded and [properly installed] conduit when exposed to direct UV? - Andrew Truitt Sent from my iPad On Mar 26, 2013, at 11:55 PM, Bill Brooks billbroo...@yahoo.com wrote: William, I have all the respect in the world for you, but I’m not referring to “basket tray”, which is only appropriate for small conductors. I’m talking about legitimate cable tray that can be up to 12” wide and that has a top and rungs every 12”. The main facilities that use it in the United States are large industrial facilities. Most electricians don’t get to work with it. It is clearly superior to EMT and is at least as good as IMC without all the hassle of threaded fittings and setting up expansion joints and worrying about 20 years of conductors thermal cycling. Even the best electricians have problems with this stuff. I am talking about projects with 800 foot long feeder runs. We can bring them in the building and build a rack for the conduit or run covered tray outside. As the 2014 NEC will require, you will have to use contactor combiners or some other means to shut down the conductors inside a building. It’s all doable. My recommendation after seeing the aftermath of rooftop conduit by good electricians is to put cable tray on roofs and use conduit if you bring the feeders indoors. It will become common practice soon. Hopefully sooner than later. Bill. From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of William Miller Sent: Tuesday, March 26, 2013 9:49 PM To: RE-wrenches Subject: Re: [RE-wrenches] Cable tray Bill: I have to disagree with you on this one. We can not abandoned a tried and true practice just because some practitioners don't do it right. I don't know how one can justify saying that encapsulating high voltage conductors in a conduit is less safe than exposed in a flimsy basket. Consider snow and ice and falling objects. Too many installers entered the PV field without first acquiring the necessary skills as journeymen or women electricians. I don't see the benefit of rewriting the code to accommodate a lack of skills in the industry. Respectfully, William Miller PS: The temperature adders always encourage us to enter the building envelope at the first appropriate location to avoid adding them. Thoughtful installers will do the same. Wm At 10:15 PM 3/25/2013, you wrote: Content-Type: multipart/alternative; boundary==_NextPart_000_00E3_01CE29A6.37CC5110 Content-Language: en-us William, I would strongly disagree that conduit is tried and true on rooftops. I have rarely seen good conduit runs on rooftops. Most electricians have no clue how to work with expansion joints. Conduit on rooftops is a bad idea in general. Most conduit runs in big buildings are all done indoors for good reason. We are the crazy people doing things on the roof. The sooner we get away from conduitparticularly for long feeder runsthe better. In Europe they don’t have problems with their rooftop wiring systems because everything is in tray. For those that don’t allow cable tray for anything less than 1/0, just remember that if it isn’t called cable tray, then 392 doesn’t apply. The NEC would allow us to use treated lumber in place of cable tray. This makes no sense. We did some research on the origin of the 1/0 requirement, and it is ancient and no longer relevant. Just because it is in the code, does not mean it is correct. That’s why we try to fix it every three years. Bill. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
Andrew,
We have used #10 USE-2 for about 16 years, and our high-elevation
New Mexico sun is quite intense. I have yet to see any degradation
exceeding fading discoloration on any conductors from that far
back, even when directly exposed to sunlight. No cracking,
peeling, delaminating, or hardening.
Allan
Allan Sindelar
al...@positiveenergysolar.com
NABCEP Certified Photovoltaic
Installer
NABCEP Certified Technical Sales Professional
New Mexico EE98J Journeyman Electrician
Founder and Chief Technology Officer
Positive Energy, Inc.
3209 Richards Lane (note new address)
Santa Fe, New Mexico 87507
505 424-1112
www.positiveenergysolar.com
On 3/27/2013 8:41 AM, Andrew Truitt wrote:
Bill - What is your take in conductor insulation degradation
over time when exposed to UV? Regardless of the "sunlight
resistant" labeling, USE-2 (and I assume PV wire though I
haven't seen it yet) does show wear after years of exposure to
direct sunlight. Maybe best practice would be to use cable
trays where conductors are shaded and [properly installed]
conduit when exposed to direct UV?
- Andrew Truitt
Sent from my iPad
On Mar 26, 2013, at 11:55 PM, "Bill Brooks" billbroo...@yahoo.com
wrote:
William,
I
have all the respect in the world for you, but Im not
referring to basket tray, which is only appropriate
for small conductors. Im talking about legitimate cable
tray that can be up to 12 wide and that has a top and
rungs every 12. The main facilities that use it in the
United States are large industrial facilities. Most
electricians dont get to work with it. It is clearly
superior to EMT and is at least as good as IMC without
all the hassle of threaded fittings and setting up
expansion joints and worrying about 20 years of
conductors thermal cycling. Even the best electricians
have problems with this stuff.
I
am talking about projects with 800 foot long feeder
runs. We can bring them in the building and build a rack
for the conduit or run covered tray outside. As the 2014
NEC will require, you will have to use contactor
combiners or some other means to shut down the
conductors inside a building. Its all doable. My
recommendation after seeing the aftermath of rooftop
conduit by good electricians is to put cable tray on
roofs and use conduit if you bring the feeders indoors.
It will become common practice soon. Hopefully sooner
than later.
Bill.
From:
re-wrenches-boun...@lists.re-wrenches.org
[mailto:re-wrenches-boun...@lists.re-wrenches.org]
On Behalf Of William Miller
Sent: Tuesday, March 26, 2013 9:49 PM
To: RE-wrenches
Subject: Re: [RE-wrenches] Cable tray
Bill:
I have to disagree with you on this one. We can not
abandoned a tried and true practice just because some
practitioners don't do it right. I don't know how one can
justify saying that encapsulating high voltage conductors
in a conduit is less safe than exposed in a flimsy
basket. Consider snow and ice and falling objects.
Too many installers entered the PV field without first
acquiring the necessary skills as journeymen or women
electricians. I don't see the benefit of rewriting the
code to accommodate a lack of skills in the industry.
Respectfully,
William Miller
PS: The temperature adders always encourage us to enter
the building envelope at the first appropriate location to
avoid adding them. Thoughtful installers will do the
same.
Wm
At 10:15 PM 3/25/2013, you wrote:
Content-Type: multipart/a
Re: [RE-wrenches] Cable tray
Exposed single conductor sunlight resistant cable in cable trays are widely used in PV systems outside the US. There is a very large installed base of systems with good long term performance data using this type of construction. We should not discount the advantages of wire cable trays just because we are unfamiliar with it. Look at data cabling - Characterized by many, relatively small, cables over long distances with periodic drops. Sounds a lot like PV source circuits (other than voltage and current in the wires of course). There are lots of videos out there showing how to pull 10's of pairs of wires simultaneously in cable trays. IMHO, we need to look at ideas like this to reduce installation cost and time. Installation costs are becoming the tall pole in the tent and new thinking is needed. As systems are falling to sub $3.00 /Watt all-in, running wire in conduit will simply not be cost effective. Running wire in conduit is one of the reasons PV installation costs in the US are double (or more) of those in Europe. As one of my former German colleagues noted: It is only in the US where you need first to be a plumber before you can be an electrician 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: 510.498.3200, X 747 M: 530.277.4894 From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Allan Sindelar Sent: Wednesday, March 27, 2013 8:51 AM To: RE-wrenches Subject: Re: [RE-wrenches] Cable tray Andrew, We have used #10 USE-2 for about 16 years, and our high-elevation New Mexico sun is quite intense. I have yet to see any degradation exceeding fading discoloration on any conductors from that far back, even when directly exposed to sunlight. No cracking, peeling, delaminating, or hardening. Allan Allan Sindelar al...@positiveenergysolar.commailto:al...@positiveenergysolar.com NABCEP Certified Photovoltaic Installer NABCEP Certified Technical Sales Professional New Mexico EE98J Journeyman Electrician Founder and Chief Technology Officer Positive Energy, Inc. 3209 Richards Lane (note new address) Santa Fe, New Mexico 87507 505 424-1112 www.positiveenergysolar.comhttp://www.positiveenergysolar.com/ On 3/27/2013 8:41 AM, Andrew Truitt wrote: Bill - What is your take in conductor insulation degradation over time when exposed to UV? Regardless of the sunlight resistant labeling, USE-2 (and I assume PV wire though I haven't seen it yet) does show wear after years of exposure to direct sunlight. Maybe best practice would be to use cable trays where conductors are shaded and [properly installed] conduit when exposed to direct UV? - Andrew Truitt Sent from my iPad On Mar 26, 2013, at 11:55 PM, Bill Brooks billbroo...@yahoo.commailto:billbroo...@yahoo.com wrote: William, I have all the respect in the world for you, but I'm not referring to basket tray, which is only appropriate for small conductors. I'm talking about legitimate cable tray that can be up to 12 wide and that has a top and rungs every 12. The main facilities that use it in the United States are large industrial facilities. Most electricians don't get to work with it. It is clearly superior to EMT and is at least as good as IMC without all the hassle of threaded fittings and setting up expansion joints and worrying about 20 years of conductors thermal cycling. Even the best electricians have problems with this stuff. I am talking about projects with 800 foot long feeder runs. We can bring them in the building and build a rack for the conduit or run covered tray outside. As the 2014 NEC will require, you will have to use contactor combiners or some other means to shut down the conductors inside a building. It's all doable. My recommendation after seeing the aftermath of rooftop conduit by good electricians is to put cable tray on roofs and use conduit if you bring the feeders indoors. It will become common practice soon. Hopefully sooner than later. Bill. From: re-wrenches-boun...@lists.re-wrenches.orgmailto:re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of William Miller Sent: Tuesday, March 26, 2013 9:49 PM To: RE-wrenches Subject: Re: [RE-wrenches] Cable tray Bill: I have to disagree with you on this one. We can not abandoned a tried and true practice just because some practitioners don't do it right. I don't know how one can justify saying that encapsulating high voltage conductors in a conduit is less safe than exposed in a flimsy basket. Consider snow and ice and falling objects. Too many installers entered the PV field without first acquiring the necessary skills as journeymen or women electricians. I don't see the benefit of rewriting the code to accommodate a lack of skills in the industry. Respectfully, William Miller PS: The temperature
Re: [RE-wrenches] Cable tray
Bill, Thank you for continuing to help adopt more practical and 'user friendly' code1 requirements. As Glen pointed out, [NEC 2011] 392.10(B)(1)(a) could pose a problem for some AHJ's - even though 690.31(B) allows PV wire in exposed outdoor locations (presumably not in cable tray). It is truly counter-intuitive that by efforting responsible wire-management and installing PV wire in cable tray it would somehow create a code violation unless it was at least 1/0, and that it would somehow be allowed in a residential application under the same 392.10? It is also interesting to note the definition of Supervised Industrial Installation2 in 240.2 and that all of those conditions are not met in most cases Just wanted to say again: Thanks for the forward progress! Mark 1 - I know, I know: user-friendly code is an oxymoron J 2 - I could not find a referenced definition of Industrial Establishments [NYLE LOGO SMALL] Mark Richardson mrichard...@newyorklightenergy.commailto:mrichard...@newyorklightenergy.com From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Bill Brooks Sent: Monday, March 25, 2013 10:54 PM To: 'RE-wrenches' Subject: Re: [RE-wrenches] Cable tray All, Here is the language that has been accepted into the 2014 NEC: 690.31(C)(2) (2) Cable Trays. PV source circuits and PV output circuits using single-conductor cable listed and labeled as Photovoltaic (PV) wire of all sizes with or without a Cable Tray marking/rating shall be permitted in cable trays installed in outdoor locations provided the cables are supported at intervals not to exceed 30cm (12 in.) and secured at intervals not to exceed 1.4m (4.5'). I hope this helps. It is a very big deal. Bill. From: re-wrenches-boun...@lists.re-wrenches.orgmailto:re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of David Brearley Sent: Monday, March 25, 2013 6:01 PM To: RE-wrenches Subject: Re: [RE-wrenches] Cable tray Ouch. I promise I'm not advocating for anything like that. What I may be missing is the Code reference that says no cable tray on roofs or similar. There is so much room for improvement in wire management practices, that being able to use cable tray seems like a step forward. I understand some jurisdictions do not allow it, but it appears as though Code changes were made specifically to address this. It's boring stuff, but you can read the explanation of the Code changes in the ROP and ROC documents. The Code changes a lot with regards to PV system, and Article 690 is more fluid than other articles. Some of this is the Code trying to keep up with technology. In other cases the Code evolves based on new applications for existing products. Often it changes because some areas of the Code are confusing for electricians and inspectors alike. If the new Code language is more clear in its intent than previous versions, some inspectors are willing to let installers build to the most current standard. That's all I'm advocating for: Trying to understand how the minimum requirements outlined in Code evolve over time so that you can have a friendly and informed conversation with your AHJ over a donut. On Mar 25, 2013, at 6:26 PM, William Miller wrote: David: This is great news. Now, whenever I want to do something that is prohibited by code, I can just say that the Code Making Panel is gonna correct that pesky code section (insert your problem citation here) any day now, so I might as well be allowed to do whatever it was I was fixin' to do anyway. Unless I am missing something... Thanks! William Miller PS: Just kidding. Hope no offense is taken. wm At 03:46 PM 3/25/2013, you wrote: So if you ever get called on 392.10(B)(2), I think you can point out that the Code Making Panels have been busy clarifying that cable tray is okay for source circuit conductors. Unless I'm missing something ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.orgmailto:RE-wrenches@lists.re-wrenches.org Change email address 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.htmhttp://www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.orghttp://www.members.re-wrenches.org inline: image002.jpg___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
Bill, Does this mean that USE-2 is not acceptable for use in this manner? Also, what is your confidence level that this will make it to the printer? I recall a few other instances of proposed amendments that at the last minute were not included in the past few code cycles (pertaining to PV). Too bad we are still on the 2008 code cycle here. Thanks Glenn Burt From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Bill Brooks Sent: Monday, March 25, 2013 10:54 PM To: 'RE-wrenches' Subject: Re: [RE-wrenches] Cable tray All, Here is the language that has been accepted into the 2014 NEC: 690.31(C)(2) (2) Cable Trays. PV source circuits and PV output circuits using single-conductor cable listed and labeled as Photovoltaic (PV) wire of all sizes with or without a Cable Tray marking/rating shall be permitted in cable trays installed in outdoor locations provided the cables are supported at intervals not to exceed 30cm (12 in.) and secured at intervals not to exceed 1.4m (4.5'). I hope this helps. It is a very big deal. Bill. From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of David Brearley Sent: Monday, March 25, 2013 6:01 PM To: RE-wrenches Subject: Re: [RE-wrenches] Cable tray Ouch. I promise I'm not advocating for anything like that. What I may be missing is the Code reference that says no cable tray on roofs or similar. There is so much room for improvement in wire management practices, that being able to use cable tray seems like a step forward. I understand some jurisdictions do not allow it, but it appears as though Code changes were made specifically to address this. It's boring stuff, but you can read the explanation of the Code changes in the ROP and ROC documents. The Code changes a lot with regards to PV system, and Article 690 is more fluid than other articles. Some of this is the Code trying to keep up with technology. In other cases the Code evolves based on new applications for existing products. Often it changes because some areas of the Code are confusing for electricians and inspectors alike. If the new Code language is more clear in its intent than previous versions, some inspectors are willing to let installers build to the most current standard. That's all I'm advocating for: Trying to understand how the minimum requirements outlined in Code evolve over time so that you can have a friendly and informed conversation with your AHJ over a donut. On Mar 25, 2013, at 6:26 PM, William Miller wrote: David: This is great news. Now, whenever I want to do something that is prohibited by code, I can just say that the Code Making Panel is gonna correct that pesky code section (insert your problem citation here) any day now, so I might as well be allowed to do whatever it was I was fixin' to do anyway. Unless I am missing something... Thanks! William Miller PS: Just kidding. Hope no offense is taken. wm At 03:46 PM 3/25/2013, you wrote: So if you ever get called on 392.10(B)(2), I think you can point out that the Code Making Panels have been busy clarifying that cable tray is okay for source circuit conductors. Unless I'm missing something ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
Not at all. Type USE cable was added to the Permitted Uses of Cable Tray, as outlined in Section 392.10(A) and the the companion Table 392.10(A). On Mar 26, 2013, at 10:02 AM, Glenn Burt wrote: Bill, Does this mean that USE-2 is not acceptable for use in this manner? Also, what is your confidence level that this will make it to the printer? I recall a few other instances of proposed amendments that at the last minute were not included in the past few code cycles (pertaining to PV). Too bad we are still on the 2008 code cycle here… Thanks Glenn Burt From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Bill Brooks Sent: Monday, March 25, 2013 10:54 PM To: 'RE-wrenches' Subject: Re: [RE-wrenches] Cable tray All, Here is the language that has been accepted into the 2014 NEC: 690.31(C)(2) (2) Cable Trays. PV source circuits and PV output circuits using single-conductor cable listed and labeled as Photovoltaic (PV) wire of all sizes with or without a Cable Tray marking/rating shall be permitted in cable trays installed in outdoor locations provided the cables are supported at intervals not to exceed 30cm (12 in.) and secured at intervals not to exceed 1.4m (4.5’). I hope this helps. It is a very big deal. Bill. From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of David Brearley Sent: Monday, March 25, 2013 6:01 PM To: RE-wrenches Subject: Re: [RE-wrenches] Cable tray Ouch. I promise I'm not advocating for anything like that. What I may be missing is the Code reference that says no cable tray on roofs or similar. There is so much room for improvement in wire management practices, that being able to use cable tray seems like a step forward. I understand some jurisdictions do not allow it, but it appears as though Code changes were made specifically to address this. It's boring stuff, but you can read the explanation of the Code changes in the ROP and ROC documents. The Code changes a lot with regards to PV system, and Article 690 is more fluid than other articles. Some of this is the Code trying to keep up with technology. In other cases the Code evolves based on new applications for existing products. Often it changes because some areas of the Code are confusing for electricians and inspectors alike. If the new Code language is more clear in its intent than previous versions, some inspectors are willing to let installers build to the most current standard. That's all I'm advocating for: Trying to understand how the minimum requirements outlined in Code evolve over time so that you can have a friendly and informed conversation with your AHJ over a donut. On Mar 25, 2013, at 6:26 PM, William Miller wrote: David: This is great news. Now, whenever I want to do something that is prohibited by code, I can just say that the Code Making Panel is gonna correct that pesky code section (insert your problem citation here) any day now, so I might as well be allowed to do whatever it was I was fixin' to do anyway. Unless I am missing something... Thanks! William Miller PS: Just kidding. Hope no offense is taken. wm At 03:46 PM 3/25/2013, you wrote: So if you ever get called on 392.10(B)(2), I think you can point out that the Code Making Panels have been busy clarifying that cable tray is okay for source circuit conductors. Unless I'm missing something ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
I don't understand how it can be permissible to string the PV wire over the rails, under the modules, and in the rail channels, but not permissible to put it in purpose made cable trays. Makes no sense. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
In a world where PV wire may be substituted for USE-2, but USE-2 cannot be substituted for PV wire, and (future) 690 wording that only refers to PV wire, there is still question in my mind about proper (future) use in cable trays when 690 over rules 392, as it does in so many other matters. The devil is in the details. From: David Brearley [mailto:david.brear...@solarprofessional.com] Sent: Tuesday, March 26, 2013 12:51 PM To: glenn.b...@glbcc.com; RE-wrenches Subject: Re: [RE-wrenches] Cable tray Not at all. Type USE cable was added to the Permitted Uses of Cable Tray, as outlined in Section 392.10(A) and the the companion Table 392.10(A). On Mar 26, 2013, at 10:02 AM, Glenn Burt wrote: Bill, Does this mean that USE-2 is not acceptable for use in this manner? Also, what is your confidence level that this will make it to the printer? I recall a few other instances of proposed amendments that at the last minute were not included in the past few code cycles (pertaining to PV). Too bad we are still on the 2008 code cycle here. Thanks Glenn Burt From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Bill Brooks Sent: Monday, March 25, 2013 10:54 PM To: 'RE-wrenches' Subject: Re: [RE-wrenches] Cable tray All, Here is the language that has been accepted into the 2014 NEC: 690.31(C)(2) (2) Cable Trays. PV source circuits and PV output circuits using single-conductor cable listed and labeled as Photovoltaic (PV) wire of all sizes with or without a Cable Tray marking/rating shall be permitted in cable trays installed in outdoor locations provided the cables are supported at intervals not to exceed 30cm (12 in.) and secured at intervals not to exceed 1.4m (4.5'). I hope this helps. It is a very big deal. Bill. From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of David Brearley Sent: Monday, March 25, 2013 6:01 PM To: RE-wrenches Subject: Re: [RE-wrenches] Cable tray Ouch. I promise I'm not advocating for anything like that. What I may be missing is the Code reference that says no cable tray on roofs or similar. There is so much room for improvement in wire management practices, that being able to use cable tray seems like a step forward. I understand some jurisdictions do not allow it, but it appears as though Code changes were made specifically to address this. It's boring stuff, but you can read the explanation of the Code changes in the ROP and ROC documents. The Code changes a lot with regards to PV system, and Article 690 is more fluid than other articles. Some of this is the Code trying to keep up with technology. In other cases the Code evolves based on new applications for existing products. Often it changes because some areas of the Code are confusing for electricians and inspectors alike. If the new Code language is more clear in its intent than previous versions, some inspectors are willing to let installers build to the most current standard. That's all I'm advocating for: Trying to understand how the minimum requirements outlined in Code evolve over time so that you can have a friendly and informed conversation with your AHJ over a donut. On Mar 25, 2013, at 6:26 PM, William Miller wrote: David: This is great news. Now, whenever I want to do something that is prohibited by code, I can just say that the Code Making Panel is gonna correct that pesky code section (insert your problem citation here) any day now, so I might as well be allowed to do whatever it was I was fixin' to do anyway. Unless I am missing something... Thanks! William Miller PS: Just kidding. Hope no offense is taken. wm At 03:46 PM 3/25/2013, you wrote: So if you ever get called on 392.10(B)(2), I think you can point out that the Code Making Panels have been busy clarifying that cable tray is okay for source circuit conductors. Unless I'm missing something ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power
Re: [RE-wrenches] Cable tray
Bill: I have to disagree with you on this one. We can not abandoned a tried and true practice just because some practitioners don't do it right. I don't know how one can justify saying that encapsulating high voltage conductors in a conduit is less safe than exposed in a flimsy basket. Consider snow and ice and falling objects. Too many installers entered the PV field without first acquiring the necessary skills as journeymen or women electricians. I don't see the benefit of rewriting the code to accommodate a lack of skills in the industry. Respectfully, William Miller PS: The temperature adders always encourage us to enter the building envelope at the first appropriate location to avoid adding them. Thoughtful installers will do the same. Wm At 10:15 PM 3/25/2013, you wrote: Content-Type: multipart/alternative; boundary==_NextPart_000_00E3_01CE29A6.37CC5110 Content-Language: en-us William, I would strongly disagree that conduit is tried and true on rooftops. I have rarely seen good conduit runs on rooftops. Most electricians have no clue how to work with expansion joints. Conduit on rooftops is a bad idea in general. Most conduit runs in big buildings are all done indoors for good reason. We are the crazy people doing things on the roof. The sooner we get away from conduitparticularly for long feeder runsthe better. In Europe they dont have problems with their rooftop wiring systems because everything is in tray. For those that dont allow cable tray for anything less than 1/0, just remember that if it isnt called cable tray, then 392 doesnt apply. The NEC would allow us to use treated lumber in place of cable tray. This makes no sense. We did some research on the origin of the 1/0 requirement, and it is ancient and no longer relevant. Just because it is in the code, does not mean it is correct. Thats why we try to fix it every three years. Bill. From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of William Miller Sent: Monday, March 25, 2013 9:30 PM To: RE-wrenches Subject: Re: [RE-wrenches] Cable tray David: Of course, I understand that you are not saying we can willfully disregard the Code in anticipation of future clarification. I was just extrapolating on your idea. If we want an exception based on a predicted update in the code, we are at the mercy of the AHJ who may or may not be convinced. I think most AHJs are willing to diverge from the Code in a more strict interpretation, but not the reverse. Right now, as I read it, unless the leads are 1/0 or larger, we are forbade. I treat PV systems like rooftop AC units. The voltages and currents are similar, if not more severe. I don't believe you could or should run power to a rooftop AC unit in cable tray. Conduit is a tried and true practice and I recommend it. William Miller At 06:01 PM 3/25/2013, you wrote: Ouch. I promise I'm not advocating for anything like that. What I may be missing is the Code reference that says no cable tray on roofs or similar. There is so much room for improvement in wire management practices, that being able to use cable tray seems like a step forward. I understand some jurisdictions do not allow it, but it appears as though Code changes were made specifically to address this. It's boring stuff, but you can read the explanation of the Code changes in the ROP and ROC documents. The Code changes a lot with regards to PV system, and Article 690 is more fluid than other articles. Some of this is the Code trying to keep up with technology. In other cases the Code evolves based on new applications for existing products. Often it changes because some areas of the Code are confusing for electricians and inspectors alike. If the new Code language is more clear in its intent than previous versions, some inspectors are willing to let installers build to the most current standard. That's all I'm advocating for: Trying to understand how the minimum requirements outlined in Code evolve over time so that you can have a friendly and informed conversation with your AHJ over a donut. On Mar 25, 2013, at 6:26 PM, William Miller wrote: David: This is great news. Now, whenever I want to do something that is prohibited by code, I can just say that the Code Making Panel is gonna correct that pesky code section (insert your problem citation here) any day now, so I might as well be allowed to do whatever it was I was fixin' to do anyway. Unless I am missing something... Thanks! William Miller PS: Just kidding. Hope no offense is taken. wm At 03:46 PM 3/25/2013, you wrote: So if you ever get called on 392.10(B)(2), I think you can point out that the Code Making Panels have been busy clarifying that cable tray is okay for source circuit conductors. Unless I'm missing something ___ List sponsored
Re: [RE-wrenches] Cable tray
William, I have all the respect in the world for you, but I'm not referring to basket tray, which is only appropriate for small conductors. I'm talking about legitimate cable tray that can be up to 12 wide and that has a top and rungs every 12. The main facilities that use it in the United States are large industrial facilities. Most electricians don't get to work with it. It is clearly superior to EMT and is at least as good as IMC without all the hassle of threaded fittings and setting up expansion joints and worrying about 20 years of conductors thermal cycling. Even the best electricians have problems with this stuff. I am talking about projects with 800 foot long feeder runs. We can bring them in the building and build a rack for the conduit or run covered tray outside. As the 2014 NEC will require, you will have to use contactor combiners or some other means to shut down the conductors inside a building. It's all doable. My recommendation after seeing the aftermath of rooftop conduit by good electricians is to put cable tray on roofs and use conduit if you bring the feeders indoors. It will become common practice soon. Hopefully sooner than later. Bill. From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of William Miller Sent: Tuesday, March 26, 2013 9:49 PM To: RE-wrenches Subject: Re: [RE-wrenches] Cable tray Bill: I have to disagree with you on this one. We can not abandoned a tried and true practice just because some practitioners don't do it right. I don't know how one can justify saying that encapsulating high voltage conductors in a conduit is less safe than exposed in a flimsy basket. Consider snow and ice and falling objects. Too many installers entered the PV field without first acquiring the necessary skills as journeymen or women electricians. I don't see the benefit of rewriting the code to accommodate a lack of skills in the industry. Respectfully, William Miller PS: The temperature adders always encourage us to enter the building envelope at the first appropriate location to avoid adding them. Thoughtful installers will do the same. Wm At 10:15 PM 3/25/2013, you wrote: Content-Type: multipart/alternative; boundary==_NextPart_000_00E3_01CE29A6.37CC5110 Content-Language: en-us William, I would strongly disagree that conduit is tried and true on rooftops. I have rarely seen good conduit runs on rooftops. Most electricians have no clue how to work with expansion joints. Conduit on rooftops is a bad idea in general. Most conduit runs in big buildings are all done indoors for good reason. We are the crazy people doing things on the roof. The sooner we get away from conduit-particularly for long feeder runs-the better. In Europe they don't have problems with their rooftop wiring systems because everything is in tray. For those that don't allow cable tray for anything less than 1/0, just remember that if it isn't called cable tray, then 392 doesn't apply. The NEC would allow us to use treated lumber in place of cable tray. This makes no sense. We did some research on the origin of the 1/0 requirement, and it is ancient and no longer relevant. Just because it is in the code, does not mean it is correct. That's why we try to fix it every three years. Bill. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
We have had good luck with Snake Trayhttp://snaketray.com/solar/ from Cable Management Solutions. Comes in Galv and Stainless, 2 x 2 or 4 x 4 [NYLE LOGO SMALL] Mark Richardson mrichard...@newyorklightenergy.commailto:mrichard...@newyorklightenergy.com From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Chris Mason Sent: Sunday, March 24, 2013 8:24 PM To: RE-wrenches Subject: Re: [RE-wrenches] Cable tray We use Cablofil but at $10/ft, it's OK for the inverter area but for large roofs, it is expensive. On Sun, Mar 24, 2013 at 3:39 PM, Kirk k...@vtsolar.commailto:k...@vtsolar.com wrote: I like William Miller's idea of slitting PVC conduit. Must be a little tricky ripping it with a saw. It's fastened to the rails using stainless clamps. There are pictures of it and other good wire mgt. on his website. I have not found a reasonably priced wire tray to attach to the rails. Especially outdoor-rated. Kirk Herander VSE On Mar 24, 2013, at 8:07 AM, Chris Mason cometenergysyst...@gmail.commailto:cometenergysyst...@gmail.com wrote: I don't want the enclosed type, I am looking for wire tray as we will support the airco pipes and some conduits. On Sat, Mar 23, 2013 at 9:33 PM, Max Balchowsky m...@seesolar.commailto:m...@seesolar.com wrote: I don't know your exact application, but I've used Carlon wireways for years. Our application most of the time was to use the 4x4 gutter in lieu of metal gutter under the inverters,disconnects, Panelboards, etc. http://www.carlonsales.com/wiresafe.php Max Balchowsky Design Engineer SEE Systems 1048 Irvine Ave Suite 217 Newport Beach, Ca. 92660 760-403-6810tel:760-403-6810 Building a Better Future For The Next Generation From: Chris Mason cometenergysyst...@gmail.commailto:cometenergysyst...@gmail.com To: RE-wrenches re-wrenches@lists.re-wrenches.orgmailto:re-wrenches@lists.re-wrenches.org Sent: Friday, March 22, 2013 12:07 PM Subject: [RE-wrenches] Cable tray I'm looking for flat roof cable tray system that is cost effective. We previously used Cablofil and Cablo-port FSL 12 tray but it is very expensive for our current application due to the size of the roof. We need to install about 200' of tray and Cablofil galvanized is eating up the budget. Can anyone recommend a cheaper alternative. -- Chris Mason ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.orgmailto:RE-wrenches@lists.re-wrenches.org Change email address 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.htmhttp://www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.orghttp://www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.orgmailto:RE-wrenches@lists.re-wrenches.org Change email address 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.htmhttp://www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.orghttp://www.members.re-wrenches.org -- Chris Mason President, Comet Systems Ltd www.cometenergysystems.comhttp://www.cometenergysystems.com Cell: 264.235.5670tel:264.235.5670 Skype: netconcepts ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.orgmailto:RE-wrenches@lists.re-wrenches.org Change email address 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.htmhttp://www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.orghttp://www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.orgmailto:RE-wrenches@lists.re-wrenches.org Change email address 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.htmhttp://www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.orghttp://www.members.re-wrenches.org -- Chris Mason President, Comet Systems Ltd www.cometenergysystems.comhttp://www.cometenergysystems.com Cell: 264.235.5670 Skype: netconcepts inline: image003.jpg___ List sponsored by Home Power
Re: [RE-wrenches] Cable tray
I think you will find it difficult to adhere to Article 392 and use a cable tray on a rooftop with source circuit conductors, if that is your hope. -Glenn From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Chris Mason Sent: Friday, March 22, 2013 3:08 PM To: RE-wrenches Subject: [RE-wrenches] Cable tray I'm looking for flat roof cable tray system that is cost effective. We previously used Cablofil and Cablo-port FSL 12 tray but it is very expensive for our current application due to the size of the roof. We need to install about 200' of tray and Cablofil galvanized is eating up the budget. Can anyone recommend a cheaper alternative. -- Chris Mason ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
What part of 392 would be a problem? On Mon, Mar 25, 2013 at 6:12 PM, Glenn Burt glenn.b...@glbcc.com wrote: I think you will find it difficult to adhere to Article 392 and use a cable tray on a rooftop with source circuit conductors, if that is your hope. ** ** -Glenn ** ** *From:* re-wrenches-boun...@lists.re-wrenches.org [mailto: re-wrenches-boun...@lists.re-wrenches.org] *On Behalf Of *Chris Mason *Sent:* Friday, March 22, 2013 3:08 PM *To:* RE-wrenches *Subject:* [RE-wrenches] Cable tray ** ** I'm looking for flat roof cable tray system that is cost effective. We previously used Cablofil and Cablo-port FSL 12 tray but it is very expensive for our current application due to the size of the roof. We need to install about 200' of tray and Cablofil galvanized is eating up the budget. Can anyone recommend a cheaper alternative. ** ** -- Chris Mason ** ** ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 -- Chris Mason President, Comet Systems Ltd www.cometenergysystems.com Cell: 264.235.5670 Skype: netconcepts ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
392.3(B)1 This was also pointed out in a recent article in Solar Pro talking about Wire Management issues. From: Chris Mason [mailto:cometenergysyst...@gmail.com] Sent: Monday, March 25, 2013 6:17 PM To: glenn.b...@glbcc.com; RE-wrenches Subject: Re: [RE-wrenches] Cable tray What part of 392 would be a problem? On Mon, Mar 25, 2013 at 6:12 PM, Glenn Burt glenn.b...@glbcc.com wrote: I think you will find it difficult to adhere to Article 392 and use a cable tray on a rooftop with source circuit conductors, if that is your hope. -Glenn From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Chris Mason Sent: Friday, March 22, 2013 3:08 PM To: RE-wrenches Subject: [RE-wrenches] Cable tray I'm looking for flat roof cable tray system that is cost effective. We previously used Cablofil and Cablo-port FSL 12 tray but it is very expensive for our current application due to the size of the roof. We need to install about 200' of tray and Cablofil galvanized is eating up the budget. Can anyone recommend a cheaper alternative. -- Chris Mason ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 -- Chris Mason President, Comet Systems Ltd www.cometenergysystems.com Cell: 264.235.5670 Skype: netconcepts ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
Uses permitted. 392.10(B)(1) requires that single conductor cable in cable tray be size 1/0 or larger. Here's the deal, though. NEC 2014 will add Service Entrance Cable: Types SE and USE to Table 392.10(A). It is not in that table now, which is why inspectors turn to 392.10(B). That means that under 390.10(A) in NEC 2014, Type USE conductor can be used in cable tray according to the methods outlined in Article 338. And references in 690.31 make it clear—if it isn't already— that PV Wire and USE-2 can generally be used interchangeably in PV systems, and that cable tray is accepted for source circuit conductors. So if you ever get called on 392.10(B)(2), I think you can point out that the Code Making Panels have been busy clarifying that cable tray is okay for source circuit conductors. Unless I'm missing something In Mar 25, 2013, at 5:17 PM, Chris Mason wrote: What part of 392 would be a problem? On Mon, Mar 25, 2013 at 6:12 PM, Glenn Burt glenn.b...@glbcc.com wrote: I think you will find it difficult to adhere to Article 392 and use a cable tray on a rooftop with source circuit conductors, if that is your hope. -Glenn From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Chris Mason Sent: Friday, March 22, 2013 3:08 PM To: RE-wrenches Subject: [RE-wrenches] Cable tray I'm looking for flat roof cable tray system that is cost effective. We previously used Cablofil and Cablo-port FSL 12 tray but it is very expensive for our current application due to the size of the roof. We need to install about 200' of tray and Cablofil galvanized is eating up the budget. Can anyone recommend a cheaper alternative. -- Chris Mason ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 -- Chris Mason President, Comet Systems Ltd www.cometenergysystems.com Cell: 264.235.5670 Skype: netconcepts ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
David: This is great news. Now, whenever I want to do something that is prohibited by code, I can just say that the Code Making Panel is gonna correct that pesky code section (insert your problem citation here) any day now, so I might as well be allowed to do whatever it was I was fixin' to do anyway. Unless I am missing something... Thanks! William Miller PS: Just kidding. Hope no offense is taken. wm At 03:46 PM 3/25/2013, you wrote: So if you ever get called on 392.10(B)(2), I think you can point out that the Code Making Panels have been busy clarifying that cable tray is okay for source circuit conductors. Unless I'm missing something ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
Again, don't have any inspectors, so it is down to me to decide if the use is reasonable and safe. On Mon, Mar 25, 2013 at 6:46 PM, David Brearley david.brear...@solarprofessional.com wrote: Uses permitted. 392.10(B)(1) requires that single conductor cable in cable tray be size 1/0 or larger. Here's the deal, though. NEC 2014 will add Service Entrance Cable: Types SE and USE to Table 392.10(A). It is not in that table now, which is why inspectors turn to 392.10(B). That means that under 390.10(A) in NEC 2014, Type USE conductor can be used in cable tray according to the methods outlined in Article 338. And references in 690.31 make it clear—if it isn't already— that PV Wire and USE-2 can generally be used interchangeably in PV systems, and that cable tray is accepted for source circuit conductors. So if you ever get called on 392.10(B)(2), I think you can point out that the Code Making Panels have been busy clarifying that cable tray is okay for source circuit conductors. Unless I'm missing something In Mar 25, 2013, at 5:17 PM, Chris Mason wrote: What part of 392 would be a problem? On Mon, Mar 25, 2013 at 6:12 PM, Glenn Burt glenn.b...@glbcc.com wrote: I think you will find it difficult to adhere to Article 392 and use a cable tray on a rooftop with source circuit conductors, if that is your hope. ** ** -Glenn ** ** *From:* re-wrenches-boun...@lists.re-wrenches.org [mailto: re-wrenches-boun...@lists.re-wrenches.org] *On Behalf Of *Chris Mason *Sent:* Friday, March 22, 2013 3:08 PM *To:* RE-wrenches *Subject:* [RE-wrenches] Cable tray ** ** I'm looking for flat roof cable tray system that is cost effective. We previously used Cablofil and Cablo-port FSL 12 tray but it is very expensive for our current application due to the size of the roof. We need to install about 200' of tray and Cablofil galvanized is eating up the budget. Can anyone recommend a cheaper alternative. ** ** -- Chris Mason ** ** ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 -- Chris Mason President, Comet Systems Ltd www.cometenergysystems.com Cell: 264.235.5670 Skype: netconcepts ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 -- Chris Mason President, Comet Systems Ltd www.cometenergysystems.com Cell: 264.235.5670 Skype: netconcepts ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
Ouch. I promise I'm not advocating for anything like that. What I may be missing is the Code reference that says no cable tray on roofs or similar. There is so much room for improvement in wire management practices, that being able to use cable tray seems like a step forward. I understand some jurisdictions do not allow it, but it appears as though Code changes were made specifically to address this. It's boring stuff, but you can read the explanation of the Code changes in the ROP and ROC documents. The Code changes a lot with regards to PV system, and Article 690 is more fluid than other articles. Some of this is the Code trying to keep up with technology. In other cases the Code evolves based on new applications for existing products. Often it changes because some areas of the Code are confusing for electricians and inspectors alike. If the new Code language is more clear in its intent than previous versions, some inspectors are willing to let installers build to the most current standard. That's all I'm advocating for: Trying to understand how the minimum requirements outlined in Code evolve over time so that you can have a friendly and informed conversation with your AHJ over a donut. On Mar 25, 2013, at 6:26 PM, William Miller wrote: David: This is great news. Now, whenever I want to do something that is prohibited by code, I can just say that the Code Making Panel is gonna correct that pesky code section (insert your problem citation here) any day now, so I might as well be allowed to do whatever it was I was fixin' to do anyway. Unless I am missing something... Thanks! William Miller PS: Just kidding. Hope no offense is taken. wm At 03:46 PM 3/25/2013, you wrote: So if you ever get called on 392.10(B)(2), I think you can point out that the Code Making Panels have been busy clarifying that cable tray is okay for source circuit conductors. Unless I'm missing something ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
All, Here is the language that has been accepted into the 2014 NEC: 690.31(C)(2) (2) Cable Trays. PV source circuits and PV output circuits using single-conductor cable listed and labeled as Photovoltaic (PV) wire of all sizes with or without a Cable Tray marking/rating shall be permitted in cable trays installed in outdoor locations provided the cables are supported at intervals not to exceed 30cm (12 in.) and secured at intervals not to exceed 1.4m (4.5'). I hope this helps. It is a very big deal. Bill. From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of David Brearley Sent: Monday, March 25, 2013 6:01 PM To: RE-wrenches Subject: Re: [RE-wrenches] Cable tray Ouch. I promise I'm not advocating for anything like that. What I may be missing is the Code reference that says no cable tray on roofs or similar. There is so much room for improvement in wire management practices, that being able to use cable tray seems like a step forward. I understand some jurisdictions do not allow it, but it appears as though Code changes were made specifically to address this. It's boring stuff, but you can read the explanation of the Code changes in the ROP and ROC documents. The Code changes a lot with regards to PV system, and Article 690 is more fluid than other articles. Some of this is the Code trying to keep up with technology. In other cases the Code evolves based on new applications for existing products. Often it changes because some areas of the Code are confusing for electricians and inspectors alike. If the new Code language is more clear in its intent than previous versions, some inspectors are willing to let installers build to the most current standard. That's all I'm advocating for: Trying to understand how the minimum requirements outlined in Code evolve over time so that you can have a friendly and informed conversation with your AHJ over a donut. On Mar 25, 2013, at 6:26 PM, William Miller wrote: David: This is great news. Now, whenever I want to do something that is prohibited by code, I can just say that the Code Making Panel is gonna correct that pesky code section (insert your problem citation here) any day now, so I might as well be allowed to do whatever it was I was fixin' to do anyway. Unless I am missing something... Thanks! William Miller PS: Just kidding. Hope no offense is taken. wm At 03:46 PM 3/25/2013, you wrote: So if you ever get called on 392.10(B)(2), I think you can point out that the Code Making Panels have been busy clarifying that cable tray is okay for source circuit conductors. Unless I'm missing something ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
Thanks Bill. That's another welcome change to look forward to in NEC 2014. On Mar 25, 2013, at 9:53 PM, Bill Brooks wrote: All, Here is the language that has been accepted into the 2014 NEC: 690.31(C)(2) (2) Cable Trays. PV source circuits and PV output circuits using single-conductor cable listed and labeled as Photovoltaic (PV) wire of all sizes with or without a Cable Tray marking/rating shall be permitted in cable trays installed in outdoor locations provided the cables are supported at intervals not to exceed 30cm (12 in.) and secured at intervals not to exceed 1.4m (4.5’). I hope this helps. It is a very big deal. Bill. From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of David Brearley Sent: Monday, March 25, 2013 6:01 PM To: RE-wrenches Subject: Re: [RE-wrenches] Cable tray Ouch. I promise I'm not advocating for anything like that. What I may be missing is the Code reference that says no cable tray on roofs or similar. There is so much room for improvement in wire management practices, that being able to use cable tray seems like a step forward. I understand some jurisdictions do not allow it, but it appears as though Code changes were made specifically to address this. It's boring stuff, but you can read the explanation of the Code changes in the ROP and ROC documents. The Code changes a lot with regards to PV system, and Article 690 is more fluid than other articles. Some of this is the Code trying to keep up with technology. In other cases the Code evolves based on new applications for existing products. Often it changes because some areas of the Code are confusing for electricians and inspectors alike. If the new Code language is more clear in its intent than previous versions, some inspectors are willing to let installers build to the most current standard. That's all I'm advocating for: Trying to understand how the minimum requirements outlined in Code evolve over time so that you can have a friendly and informed conversation with your AHJ over a donut. On Mar 25, 2013, at 6:26 PM, William Miller wrote: David: This is great news. Now, whenever I want to do something that is prohibited by code, I can just say that the Code Making Panel is gonna correct that pesky code section (insert your problem citation here) any day now, so I might as well be allowed to do whatever it was I was fixin' to do anyway. Unless I am missing something... Thanks! William Miller PS: Just kidding. Hope no offense is taken. wm At 03:46 PM 3/25/2013, you wrote: So if you ever get called on 392.10(B)(2), I think you can point out that the Code Making Panels have been busy clarifying that cable tray is okay for source circuit conductors. Unless I'm missing something ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
David: Of course, I understand that you are not saying we can willfully disregard the Code in anticipation of future clarification. I was just extrapolating on your idea. If we want an exception based on a predicted update in the code, we are at the mercy of the AHJ who may or may not be convinced. I think most AHJs are willing to diverge from the Code in a more strict interpretation, but not the reverse. Right now, as I read it, unless the leads are 1/0 or larger, we are forbade. I treat PV systems like rooftop AC units. The voltages and currents are similar, if not more severe. I don't believe you could or should run power to a rooftop AC unit in cable tray. Conduit is a tried and true practice and I recommend it. William Miller At 06:01 PM 3/25/2013, you wrote: Ouch. I promise I'm not advocating for anything like that. What I may be missing is the Code reference that says no cable tray on roofs or similar. There is so much room for improvement in wire management practices, that being able to use cable tray seems like a step forward. I understand some jurisdictions do not allow it, but it appears as though Code changes were made specifically to address this. It's boring stuff, but you can read the explanation of the Code changes in the ROP and ROC documents. The Code changes a lot with regards to PV system, and Article 690 is more fluid than other articles. Some of this is the Code trying to keep up with technology. In other cases the Code evolves based on new applications for existing products. Often it changes because some areas of the Code are confusing for electricians and inspectors alike. If the new Code language is more clear in its intent than previous versions, some inspectors are willing to let installers build to the most current standard. That's all I'm advocating for: Trying to understand how the minimum requirements outlined in Code evolve over time so that you can have a friendly and informed conversation with your AHJ over a donut. On Mar 25, 2013, at 6:26 PM, William Miller wrote: David: This is great news. Now, whenever I want to do something that is prohibited by code, I can just say that the Code Making Panel is gonna correct that pesky code section (insert your problem citation here) any day now, so I might as well be allowed to do whatever it was I was fixin' to do anyway. Unless I am missing something... Thanks! William Miller PS: Just kidding. Hope no offense is taken. wm At 03:46 PM 3/25/2013, you wrote: So if you ever get called on 392.10(B)(2), I think you can point out that the Code Making Panels have been busy clarifying that cable tray is okay for source circuit conductors. Unless I'm missing something ___ List sponsored by Home Power magazine List Address: mailto:RE-wrenches@lists.re-wrenches.orgRE-wrenches@lists.re-wrenches.org Change email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.orghttp://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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 Miller Solar Voice :805-438-5600 email: will...@millersolar.com http://millersolar.com License No. C-10-773985 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
William, I would strongly disagree that conduit is tried and true on rooftops. I have rarely seen good conduit runs on rooftops. Most electricians have no clue how to work with expansion joints. Conduit on rooftops is a bad idea in general. Most conduit runs in big buildings are all done indoors for good reason. We are the crazy people doing things on the roof. The sooner we get away from conduit-particularly for long feeder runs-the better. In Europe they don't have problems with their rooftop wiring systems because everything is in tray. For those that don't allow cable tray for anything less than 1/0, just remember that if it isn't called cable tray, then 392 doesn't apply. The NEC would allow us to use treated lumber in place of cable tray. This makes no sense. We did some research on the origin of the 1/0 requirement, and it is ancient and no longer relevant. Just because it is in the code, does not mean it is correct. That's why we try to fix it every three years. Bill. From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of William Miller Sent: Monday, March 25, 2013 9:30 PM To: RE-wrenches Subject: Re: [RE-wrenches] Cable tray David: Of course, I understand that you are not saying we can willfully disregard the Code in anticipation of future clarification. I was just extrapolating on your idea. If we want an exception based on a predicted update in the code, we are at the mercy of the AHJ who may or may not be convinced. I think most AHJs are willing to diverge from the Code in a more strict interpretation, but not the reverse. Right now, as I read it, unless the leads are 1/0 or larger, we are forbade. I treat PV systems like rooftop AC units. The voltages and currents are similar, if not more severe. I don't believe you could or should run power to a rooftop AC unit in cable tray. Conduit is a tried and true practice and I recommend it. William Miller At 06:01 PM 3/25/2013, you wrote: Ouch. I promise I'm not advocating for anything like that. What I may be missing is the Code reference that says no cable tray on roofs or similar. There is so much room for improvement in wire management practices, that being able to use cable tray seems like a step forward. I understand some jurisdictions do not allow it, but it appears as though Code changes were made specifically to address this. It's boring stuff, but you can read the explanation of the Code changes in the ROP and ROC documents. The Code changes a lot with regards to PV system, and Article 690 is more fluid than other articles. Some of this is the Code trying to keep up with technology. In other cases the Code evolves based on new applications for existing products. Often it changes because some areas of the Code are confusing for electricians and inspectors alike. If the new Code language is more clear in its intent than previous versions, some inspectors are willing to let installers build to the most current standard. That's all I'm advocating for: Trying to understand how the minimum requirements outlined in Code evolve over time so that you can have a friendly and informed conversation with your AHJ over a donut. On Mar 25, 2013, at 6:26 PM, William Miller wrote: David: This is great news. Now, whenever I want to do something that is prohibited by code, I can just say that the Code Making Panel is gonna correct that pesky code section (insert your problem citation here) any day now, so I might as well be allowed to do whatever it was I was fixin' to do anyway. Unless I am missing something... Thanks! William Miller PS: Just kidding. Hope no offense is taken. wm At 03:46 PM 3/25/2013, you wrote: So if you ever get called on 392.10(B)(2), I think you can point out that the Code Making Panels have been busy clarifying that cable tray is okay for source circuit conductors. Unless I'm missing something ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 http://www.members.re-wrenches.org/ ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 http://www.members.re-wrenches.org/ Miller Solar Voice :805-438-5600 email: will...@millersolar.com http
Re: [RE-wrenches] Cable tray
I don't want the enclosed type, I am looking for wire tray as we will support the airco pipes and some conduits. On Sat, Mar 23, 2013 at 9:33 PM, Max Balchowsky m...@seesolar.com wrote: I don't know your exact application, but I've used Carlon wireways for years. Our application most of the time was to use the 4x4 gutter in lieu of metal gutter under the inverters,disconnects, Panelboards, etc. http://www.carlonsales.com/wiresafe.php Max Balchowsky Design Engineer SEE Systems 1048 Irvine Ave Suite 217 Newport Beach, Ca. 92660 760-403-6810 Building a Better Future For The Next Generation -- *From:* Chris Mason cometenergysyst...@gmail.com *To:* RE-wrenches re-wrenches@lists.re-wrenches.org *Sent:* Friday, March 22, 2013 12:07 PM *Subject:* [RE-wrenches] Cable tray I'm looking for flat roof cable tray system that is cost effective. We previously used Cablofil and Cablo-port FSL 12 tray but it is very expensive for our current application due to the size of the roof. We need to install about 200' of tray and Cablofil galvanized is eating up the budget. Can anyone recommend a cheaper alternative. -- Chris Mason ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 -- Chris Mason President, Comet Systems Ltd www.cometenergysystems.com Cell: 264.235.5670 Skype: netconcepts ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
I like William Miller's idea of slitting PVC conduit. Must be a little tricky ripping it with a saw. It's fastened to the rails using stainless clamps. There are pictures of it and other good wire mgt. on his website. I have not found a reasonably priced wire tray to attach to the rails. Especially outdoor-rated. Kirk Herander VSE On Mar 24, 2013, at 8:07 AM, Chris Mason cometenergysyst...@gmail.com wrote: I don't want the enclosed type, I am looking for wire tray as we will support the airco pipes and some conduits. On Sat, Mar 23, 2013 at 9:33 PM, Max Balchowsky m...@seesolar.com wrote: I don't know your exact application, but I've used Carlon wireways for years. Our application most of the time was to use the 4x4 gutter in lieu of metal gutter under the inverters,disconnects, Panelboards, etc. http://www.carlonsales.com/wiresafe.php Max Balchowsky Design Engineer SEE Systems 1048 Irvine Ave Suite 217 Newport Beach, Ca. 92660 760-403-6810 Building a Better Future For The Next Generation From: Chris Mason cometenergysyst...@gmail.com To: RE-wrenches re-wrenches@lists.re-wrenches.org Sent: Friday, March 22, 2013 12:07 PM Subject: [RE-wrenches] Cable tray I'm looking for flat roof cable tray system that is cost effective. We previously used Cablofil and Cablo-port FSL 12 tray but it is very expensive for our current application due to the size of the roof. We need to install about 200' of tray and Cablofil galvanized is eating up the budget. Can anyone recommend a cheaper alternative. -- Chris Mason ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 -- Chris Mason President, Comet Systems Ltd www.cometenergysystems.com Cell: 264.235.5670 Skype: netconcepts ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
We use Cablofil but at $10/ft, it's OK for the inverter area but for large roofs, it is expensive. On Sun, Mar 24, 2013 at 3:39 PM, Kirk k...@vtsolar.com wrote: I like William Miller's idea of slitting PVC conduit. Must be a little tricky ripping it with a saw. It's fastened to the rails using stainless clamps. There are pictures of it and other good wire mgt. on his website. I have not found a reasonably priced wire tray to attach to the rails. Especially outdoor-rated. Kirk Herander VSE On Mar 24, 2013, at 8:07 AM, Chris Mason cometenergysyst...@gmail.com wrote: I don't want the enclosed type, I am looking for wire tray as we will support the airco pipes and some conduits. On Sat, Mar 23, 2013 at 9:33 PM, Max Balchowsky m...@seesolar.com wrote: I don't know your exact application, but I've used Carlon wireways for years. Our application most of the time was to use the 4x4 gutter in lieu of metal gutter under the inverters,disconnects, Panelboards, etc. http://www.carlonsales.com/wiresafe.php Max Balchowsky Design Engineer SEE Systems 1048 Irvine Ave Suite 217 Newport Beach, Ca. 92660 760-403-6810 Building a Better Future For The Next Generation -- *From:* Chris Mason cometenergysyst...@gmail.com *To:* RE-wrenches re-wrenches@lists.re-wrenches.org *Sent:* Friday, March 22, 2013 12:07 PM *Subject:* [RE-wrenches] Cable tray I'm looking for flat roof cable tray system that is cost effective. We previously used Cablofil and Cablo-port FSL 12 tray but it is very expensive for our current application due to the size of the roof. We need to install about 200' of tray and Cablofil galvanized is eating up the budget. Can anyone recommend a cheaper alternative. -- Chris Mason ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 -- Chris Mason President, Comet Systems Ltd www.cometenergysystems.com Cell: 264.235.5670 Skype: netconcepts ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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 -- Chris Mason President, Comet Systems Ltd www.cometenergysystems.com Cell: 264.235.5670 Skype: netconcepts ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray
I don't know your exact application, but I've used Carlon wireways for years. Our application most of the time was to use the 4x4 gutter in lieu of metal gutter under the inverters,disconnects, Panelboards, etc. http://www.carlonsales.com/wiresafe.php Max Balchowsky Design Engineer SEE Systems 1048 Irvine Ave Suite 217 Newport Beach, Ca. 92660 760-403-6810 Building a Better Future For The Next Generation From: Chris Mason cometenergysyst...@gmail.com To: RE-wrenches re-wrenches@lists.re-wrenches.org Sent: Friday, March 22, 2013 12:07 PM Subject: [RE-wrenches] Cable tray I'm looking for flat roof cable tray system that is cost effective. We previously used Cablofil and Cablo-port FSL 12 tray but it is very expensive for our current application due to the size of the roof. We need to install about 200' of tray and Cablofil galvanized is eating up the budget. Can anyone recommend a cheaper alternative. -- Chris Mason ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address 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] Cable tray versus RMC
Larry, We do have the option of no roof penetrations and that is the course being taken. We will have 90 source circuits in the array and 5 Jboxes on the roof and these will then be routed to a vertical wall on the west end of the array. The strings will carry through the wall horizontally and then on to the inverters. My preference would have been to penetrate the roof with RMC and come directly into the bottom of the NEMA 4X Jbox avoiding the long conduit runs across the roof ( which will be visible from gorund level). I have used the DEKTite (http://www.itwbuildex.com/gcs_flashings_dektite.shtml) roof boot for this type of penetration in the past with good success. We use the Eternabond double face adhesive on the bottom of the boot. WIth the boot fully under the JBox it will never see the light of day and should last as long as the array. The point of my original post was really to find out if the cable tray approach has been used by other installers for managing the DC source circuit wiring on rooftops. Will it meet code? My understanding is that cable tray is not classified as a raceway. It it good practice? That sort of thing. I personally would feel better if the source circuits were in RMC. Cheers Carl On Mon, Feb 14, 2011 at 4:37 PM, wire...@gmail.com wrote: Carl, I also have a job on a brand new SS metal roof and I just did not want put any holes in it so I am going down the side of the building and not penetrating at all. But it's only 50kW. Do you have the option of no penetration? I am curious though as to what j-box/sealing/flashing set up you were planning on using. Larry Liesner Wirewiz Westport, CT Phone: 203-644-2404 Fax: 203-557-0556 wire...@gmail.com www.wire-wiz.com On Feb 14, 2011, at 2:56 PM, Carl Adams wrote: I have a project for 250kW system. 4/12 pitch standing seem roof in the Great Lakes snow country. My initial proposal was to get the source strings through the roof and inside to serviceable combiner locations. This was shot down by the architect who did not want 5 holes punched in his new roof. So we then shift to pass thru Jboxes where we transition the PV wire to THWN-2 and into RMC back to the desired point of entry. The electrical sub on the project has now proposed to reduce expense by replacing the RMC with cable trays and running USE-2 in the cable tray from the JBOX back to the point of entry. I'd appreciate your thoughts on the use of the cable tray and USE-2 on the roof top. WIth REgards Carl Adams NABCEP cert 031508-1 ___ 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 ___ 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 ___ 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
