Re: [RE-wrenches] Rapid shutdown questions
HI Dan, If you are doing 24v battery or below, you should be able to ignore the battery rapid shutdown part. IE under 30v jay peltz power On Aug 30, 2014, at 2:04 PM, Dan Fink wrote: Dave; I feel your pain as do many others. I feel like I've been Rick-rolled on the whole 690.12 thing. As a firefighter, I thought rapid shutdown was a great idea for roof mounted arrays. Shut down fast from a central location on the ground, get up on the roof, do what needs to be done, fast and no worries other than the fire itself. But disconnects hanging 15 feet in the air? Allowed to mount them in the attic through a locked door to a disused lavatory behind a file cabinet labeled beware of the leopard? - meets code. Rapid shutdown for ground mount arrays? Just walk over to the danged thing and throw the clearly-labeled disconnects, the central signage told you where they are. Problem solved. All just plain silly, counterproductive and expensive for the homeowner. As I work exclusively with off-grid systems, most of them ranging from small to tiny, I've been seeing their potential client's eyes go wide as dinner plates when I inform them By the way, Colorado just adopted NEC 2014, and it'll be an extra $1500 to comply, sorry that's a 33% increase in your system cost.. What's happening in the real world is folks getting the household 120/240 AC wiring signed off as powered by gasoline generator and they do the solar later, and change the gate combo so the inspector can't come back. Now *that's* counterproductive. Robin, glad to hear clarifications are coming in 2017. Dan Fink Buckville Energy IREC Certified Instructor™ - PV Installation Professional and Small Wind Installer 970.672.4342 On Fri, Aug 29, 2014 at 11:08 AM, Dave Click davecl...@fsec.ucf.edu wrote: While I share Robin's optimism, I should also note the NEC 2017 690.12 committee referred to is not the code making panel. While it does have (at least) one firefighter representative among a majority of PV industry personnel, there's no guarantee that the Code Making Panel approves this committee's proposal. There could very well be a competing proposal from firefighters that requires cell-level shutdown every time a red truck drives within 1/4 mile of an array, because SAFETY! DKC ___ 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 ___ 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] Rapid shutdown questions
Hello Robin and boB. Ryans Midnite video of the Birdhouse and rapid shutdown disconnects is amazing. It does look like you are producing a means of implementing this new code rule. In many situations, the rapid shutdown requirement certainly makes sense. In a large system where high voltages and currents are present over large areas of solar array, major safety features need to be in place. The extra cost of the rapid shutdown equipment and its installation likely wouldn't produce much of an obstacle to the budget of a major commercial installation. A very nice feature of todays lower module prices is that many people who really want PV, but have never been able to afford it, can now have a system. New requirements are eroding this new found ability. I would like to suggest the use of hazard-based criteria to decide if rapid shutdown is to be required. A small cabin system with 750 W of PV, a Kid charge control, and a couple of L-16 batteries should clearly be excused from any rapid shutdown requirement. The system is easy to understand, and can be disabled quickly. The requirement should be applied only to systems that have a large amount of power. The level of hazard could be evaluated for different scenarios. What is the demonstrated hazard of a 9.6 kW system feeding a pair of Classics and a fused battery bank? How many problems have been reported with properly installed systems of this size? What is the arc potential? Please keep in mind that a standard 120/240 V grid connection can have an open wire running 10 feet above the yard, which can run as much as 25 feet down the side of a house, in unprotected Service Entrance Cable. This wire may have a 10,000 Amp (or greater) short circuit current at 240 Vand this wire can't be shut off. Therefore, 2,400 kW is available! Why can't a few kW of PV be run down the side of a house in metal conduit? What are the statistics that demonstrate that small PV systems are significant safety hazards? Are there real statistics, rather than anecdotal events? There were an estimated http://www.thecarconnection.com/news/1090330_early-estimate-35200-traffic-deaths-in-2013-a-drop-of-3-from-201232,500 traffic deaths in 2013. How many people were killed by solar electric systems that year? How about an exemption for residential systems under 12 kW? This size system has a power potential of 1/200th of that of the wire that runs 10 feet over your back yard with no protectionwhich you can't shut off! Given the good safety record of PV, maybe we can keep existing standards for smaller systemsones that won't add unnecessary expenses that keep these systems from ever being built. Drake Drake Chamberlin Athens Electric LLC OH License 44810 CO License 3773 NABCEP Certified Solar PV 740-448-7328 http://athens-electric.com/http://athens-electric.com/ At 03:16 PM 8/28/2014, you wrote: [Robin chiming in, below] Dan, The 2014 690.12 is worded poorly. That is why there is so much confusion. MidNite Solar is sitting on the NEC2017 690.12 committee. There are a lot of smart people in this group. The 2017 version says ALL PV SYSTEMS, not just on or in buildings. The 10 foot space gets reduced to 1 foot like it always should have been. There will be a lot of other clarifications too. The systems that use shunt trip breakers [with Remote Trip coil] and contactors are for string inverters. Shunt trip breakers will be used for battery based systems and grid tie inverters with an AC outlet like the SMA TL series. Micro inverters do not require anything like what our system is. They can use the existing backfed breaker in the main distribution box as long as it is labeled accordingly. Solar Edge has a system that meets the Rapid Shutdown requirement also. The UL standard for Rapid Shutdown has been written. It is going to go out to a task force for review, comment and changes soon. MidNite Solar will be on that task force. The MidNite Birdhouse is going through UL now and is being evaluated to this new standard. All of our disconnecting combiners and SOBs are already ETL listed. UL is modifying the new Rapid Shutdown Draft standard as they come upon things in the Birdhouse that the standard didn't consider. One of the biggies that has not been sorted out is a requirement for feedback. Contactors, power supplies and a switch will meet the requirement for 2014. The issue with this type of system is that when you push the button to turn off the contactors, there is no way to tell that they actually opened up. Without feedback that verifies that the contactors are actually open, you are taking a chance with people's lives. 600VDC contactors can weld themselves closed. If first responders don't trust the Rapid Shutdown system, they are going to let the house burn. We do have feedback on the birdhouse system. Contactors do not have feedback. It is not simple to add this feature to
Re: [RE-wrenches] Rapid shutdown questions
Dave; I feel your pain as do many others. I feel like I've been Rick-rolled on the whole 690.12 thing. As a firefighter, I thought rapid shutdown was a great idea for roof mounted arrays. Shut down fast from a central location on the ground, get up on the roof, do what needs to be done, fast and no worries other than the fire itself. But disconnects hanging 15 feet in the air? Allowed to mount them in the attic through a locked door to a disused lavatory behind a file cabinet labeled beware of the leopard? - meets code. Rapid shutdown for ground mount arrays? Just walk over to the danged thing and throw the clearly-labeled disconnects, the central signage told you where they are. Problem solved. All just plain silly, counterproductive and expensive for the homeowner. As I work exclusively with off-grid systems, most of them ranging from small to tiny, I've been seeing their potential client's eyes go wide as dinner plates when I inform them By the way, Colorado just adopted NEC 2014, and it'll be an extra $1500 to comply, sorry that's a 33% increase in your system cost.. What's happening in the real world is folks getting the household 120/240 AC wiring signed off as powered by gasoline generator and they do the solar later, and change the gate combo so the inspector can't come back. Now *that's* counterproductive. Robin, glad to hear clarifications are coming in 2017. Dan Fink Buckville Energy IREC Certified Instructor™ - PV Installation Professional and Small Wind Installer 970.672.4342 On Fri, Aug 29, 2014 at 11:08 AM, Dave Click davecl...@fsec.ucf.edu wrote: While I share Robin's optimism, I should also note the NEC 2017 690.12 committee referred to is not the code making panel. While it does have (at least) one firefighter representative among a majority of PV industry personnel, there's no guarantee that the Code Making Panel approves this committee's proposal. There could very well be a competing proposal from firefighters that requires cell-level shutdown every time a red truck drives within 1/4 mile of an array, because SAFETY! DKC ___ 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] Rapid shutdown questions
While I share Robin's optimism, I should also note the NEC 2017 690.12 committee referred to is not the code making panel. While it does have (at least) one firefighter representative among a majority of PV industry personnel, there's no guarantee that the Code Making Panel approves this committee's proposal. There could very well be a competing proposal from firefighters that requires cell-level shutdown every time a red truck drives within 1/4 mile of an array, because SAFETY! DKC On 2014/8/28, 15:16, b...@midnitesolar.com wrote: [Robin chiming in, below] Dan, The 2014 690.12 is worded poorly. That is why there is so much confusion. MidNite Solar is sitting on the NEC2017 690.12 committee. There are a lot of smart people in this group. The 2017 version says ALL PV SYSTEMS, not just on or in buildings. The 10 foot space gets reduced to 1 foot like it always should have been. There will be a lot of other clarifications too. The systems that use shunt trip breakers [with Remote Trip coil] and contactors are for string inverters. Shunt trip breakers will be used for battery based systems and grid tie inverters with an AC outlet like the SMA TL series. Micro inverters do not require anything like what our system is. They can use the existing backfed breaker in the main distribution box as long as it is labeled accordingly. Solar Edge has a system that meets the Rapid Shutdown requirement also. The UL standard for Rapid Shutdown has been written. It is going to go out to a task force for review, comment and changes soon. MidNite Solar will be on that task force. The MidNite Birdhouse is going through UL now and is being evaluated to this new standard. All of our disconnecting combiners and SOBs are already ETL listed. UL is modifying the new Rapid Shutdown Draft standard as they come upon things in the Birdhouse that the standard didn't consider. One of the biggies that has not been sorted out is a requirement for feedback. Contactors, power supplies and a switch will meet the requirement for 2014. The issue with this type of system is that when you push the button to turn off the contactors, there is no way to tell that they actually opened up. Without feedback that verifies that the contactors are actually open, you are taking a chance with people's lives. 600VDC contactors can weld themselves closed. If first responders don't trust the Rapid Shutdown system, they are going to let the house burn. We do have feedback on the birdhouse system. Contactors do not have feedback. It is not simple to add this feature to a contactor based system. Installing a switch 15 feet up on the side of a building or on the roof is not the intent of 690.12. This will not be allowed in 2017. The exact placement of the initiating device (Birdhouse) is not cast in concrete due to the differences in where main panel boards are located, but it will not allow things like mentioned here 15 feet up in the air or in the attic or on the roof. Battery based systems are the most complicated to meet 690.12. The NEC committee is deferring a lot of this to MidNite as we are already doing it and have gone over all the different ways things can go wrong. We started designing our system right after the Bakersfield fire 5 years ago. The Bakersfield fire is what got the NEC to require disconnecting combiners. We couldn't imagine why a fire fighter would want to get up on the roof of a burning building to look for a combiner? This is why we started the birdhouse project way before anyone ever thought of the words Rapid Shutdown. Turns out this was a good thing since battery backed up systems make the issue ten times more complicated. We spent years working out issues and there were lots of them that required a start from scratch approach numerous times. AC coupling to a battery based inverter does not automatically meet 690.12 as someone mentioned in this thread. That battery based inverter must also be shut off. The micro inverters would of course shut off when the utility is shut down, but the battery based inverters job is to keep things powered up when the grid is down. So the battery based inverter has to be shut down also. It would also make sense to shut off an auto start generator with the Rapid Shutdown button. Some generators are designed to start up upon loss of grid. Once the first responders have the meter pulled, that could start up a generator and cause risk of shock. If the generator is designed to start on low battery, it could start a day later when the fire has been put out, but that also poses risk of electrical shock when unexpectedly the part of the house that is left all of a sudden comes live with juice. The cost for a Rapid Shutdown system will vary a lot depending on what you want to shut down. You do not need to run conduit to all the boxes and switches. There is 600V Cat5e 90C USE-2 cable available that will suffice. I don't see a
Re: [RE-wrenches] Rapid shutdown questions
[Robin chiming in, below] Dan, The 2014 690.12 is worded poorly. That is why there is so much confusion. MidNite Solar is sitting on the NEC2017 690.12 committee. There are a lot of smart people in this group. The 2017 version says ALL PV SYSTEMS, not just on or in buildings. The 10 foot space gets reduced to 1 foot like it always should have been. There will be a lot of other clarifications too. The systems that use shunt trip breakers [with Remote Trip coil] and contactors are for string inverters. Shunt trip breakers will be used for battery based systems and grid tie inverters with an AC outlet like the SMA TL series. Micro inverters do not require anything like what our system is. They can use the existing backfed breaker in the main distribution box as long as it is labeled accordingly. Solar Edge has a system that meets the Rapid Shutdown requirement also. The UL standard for Rapid Shutdown has been written. It is going to go out to a task force for review, comment and changes soon. MidNite Solar will be on that task force. The MidNite Birdhouse is going through UL now and is being evaluated to this new standard. All of our disconnecting combiners and SOBs are already ETL listed. UL is modifying the new Rapid Shutdown Draft standard as they come upon things in the Birdhouse that the standard didn't consider. One of the biggies that has not been sorted out is a requirement for feedback. Contactors, power supplies and a switch will meet the requirement for 2014. The issue with this type of system is that when you push the button to turn off the contactors, there is no way to tell that they actually opened up. Without feedback that verifies that the contactors are actually open, you are taking a chance with people's lives. 600VDC contactors can weld themselves closed. If first responders don't trust the Rapid Shutdown system, they are going to let the house burn. We do have feedback on the birdhouse system. Contactors do not have feedback. It is not simple to add this feature to a contactor based system. Installing a switch 15 feet up on the side of a building or on the roof is not the intent of 690.12. This will not be allowed in 2017. The exact placement of the initiating device (Birdhouse) is not cast in concrete due to the differences in where main panel boards are located, but it will not allow things like mentioned here 15 feet up in the air or in the attic or on the roof. Battery based systems are the most complicated to meet 690.12. The NEC committee is deferring a lot of this to MidNite as we are already doing it and have gone over all the different ways things can go wrong. We started designing our system right after the Bakersfield fire 5 years ago. The Bakersfield fire is what got the NEC to require disconnecting combiners. We couldn't imagine why a fire fighter would want to get up on the roof of a burning building to look for a combiner? This is why we started the birdhouse project way before anyone ever thought of the words Rapid Shutdown. Turns out this was a good thing since battery backed up systems make the issue ten times more complicated. We spent years working out issues and there were lots of them that required a start from scratch approach numerous times. AC coupling to a battery based inverter does not automatically meet 690.12 as someone mentioned in this thread. That battery based inverter must also be shut off. The micro inverters would of course shut off when the utility is shut down, but the battery based inverters job is to keep things powered up when the grid is down. So the battery based inverter has to be shut down also. It would also make sense to shut off an auto start generator with the Rapid Shutdown button. Some generators are designed to start up upon loss of grid. Once the first responders have the meter pulled, that could start up a generator and cause risk of shock. If the generator is designed to start on low battery, it could start a day later when the fire has been put out, but that also poses risk of electrical shock when unexpectedly the part of the house that is left all of a sudden comes live with juice. The cost for a Rapid Shutdown system will vary a lot depending on what you want to shut down. You do not need to run conduit to all the boxes and switches. There is 600V Cat5e 90C USE-2 cable available that will suffice. I don't see a system being installed for less than $1500 though. Robin Gudgels On 8/27/2014 8:45 AM, Dan Fink wrote: Hi Mac, all; Since Colorado just adopted NEC2014 July 1, I have not heard any AHJ stories yet. But look at 690.12 (1): Requirements for controlled conductors shall apply only to PV system conductors of more than 5 ft in length inside a building, OR more than 10 ft from a PV array. (my emphasis on OR) I interpret this to mean that if a ground mount array is more than 10 ft from the building, then any PV circuits that run up the
Re: [RE-wrenches] Rapid shutdown questions
So this would make sense that this Rapid Shut down provision would cover all generator backup systems too, not just solar. Considering auto start backup generators have been around for many decades, I have a few questions: 1) Does NEC 2014 require Rapid shutdown for all generator systems, or is solar once again being singled out for additional requirements not applied to everyone else? 2) What is the history of fire fighting and backup generators? It seems that there would be much more long term experience, than a hand full of incidents in the solar industry. 3) What about portable generators, and folks back feeding the grid or house with little to no protection at all. Are there safety precautions that fire fighters take to make sure a neighbor isn't powering up lines down the street? I've seen too many male to male extension cords, so I know this is real issue, that can't be prevented by the NEC code alone. Basically any idiot can go to Home depot and create a very dangerous situation quickly. R.Ray Walters CTO, Solarray, Inc Nabcep Certified PV Installer, Licensed Master Electrician Solar Design Engineer 303 505-8760 On 8/28/2014 1:16 PM, b...@midnitesolar.com wrote: It would also make sense to shut off an auto start generator with the Rapid Shutdown button. Some generators are designed to start up upon loss of grid. Once the first responders have the meter pulled, that could start up a generator and cause risk of shock. Robin Gudgels ___ 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] Rapid shutdown questions
Our experience in MA with rapid shutdown unfortunately varies with AHJ. Some are letting us put an Eaton NEMA 4 disconnect on the roof next to the array. Some are letting us put a disconnect in an accessible attic within 5’ of the penetration. Some are requiring the Midnight Birdhouse remote switch which is expensive. Rapid shutdown doesn’t apply to pole or ground mounts. Hope this helps. Will Will White Operations Manager - New England RGS Energy 64 Main St. |Montpelier, VT 05602 tel 802.223.7804 | mobile 802.234.3167 | fax 802.223.8980 RGSEnergy.comhttp://www.rgsenergy.com/ | william.wh...@rgsenergy.commailto:william.wh...@rgsenergy.com Confidentiality Note: This e-mail message may contain confidential or legally privileged information and is intended only for the use of the intended recipient(s). Any unauthorized disclosure, dissemination, distribution, copying or the taking of any action in reliance on the information herein is prohibited. E-mails are not secure and cannot be guaranteed to be error free as they can be intercepted, amended, or contain viruses. Anyone who communicates with us by e-mail is deemed to have accepted these risks. RGS Energy is not responsible for errors or omissions in this message and denies any responsibility for any damage arising from the use of e-mail. Any opinion and other statement contained in this message and any attachment are solely those of the author and do not necessarily represent those of the company. From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Mac Lewis Sent: Wednesday, August 27, 2014 8:32 AM To: RE-wrenches Subject: [RE-wrenches] Rapid shutdown questions Hello wrenches, I am still trying to wrap my head around how to comply with rapid shutdown in off-grid and hybrid situations. I've got a few questions that maybe you can help with. 1. What is a (currently listed) rapid shutdown system that will accommodate 8 strings? I know I can do this with Midnite combiners but as I understand these aren't listed yet. 2. On a remote pole mount, does rapid shutdown apply? If the intent is to isolate a safe zone around an array for fire fighting, it seems as though a standard pole mounted DC disconnect can cover this concern. 3. I estimate on a typical hybrid installation, rapid shutdown will cost at least $3000 to implement. This includes remote shunt trip battery breakers, contactors on PV side of charge controller and roof combiners, and running control cable from remote disconnect to all locations. As of now, this would also require me to modify listed interconnection equipment. Is this what others are finding? 4. AC coupling with microinverters may be the easiest way to comply with most of these requirements. However, this doesn't seem like a great alternative to the standard charge controller installation in an off-grid system. Thanks in advance for your thoughts -- Mac Lewis Yo solo sé que no sé nada. -Sócrates ___ 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] Rapid shutdown questions
Hi Will, Yes I'm sure AHJ's will be all over the place for a while here in Colorado. To clarify, is this a manual disconnect in the attic? If so, that is really missing the whole idea of a rapid shutdown. Thanks On Wed, Aug 27, 2014 at 7:47 AM, Will White william.wh...@rgsenergy.com wrote: Our experience in MA with rapid shutdown unfortunately varies with AHJ. Some are letting us put an Eaton NEMA 4 disconnect on the roof next to the array. Some are letting us put a disconnect in an accessible attic within 5’ of the penetration. Some are requiring the Midnight Birdhouse remote switch which is expensive. Rapid shutdown doesn’t apply to pole or ground mounts. Hope this helps. Will *Will White* Operations Manager - New England RGS Energy 64 Main St. |Montpelier, VT 05602 tel 802.223.7804 | mobile 802.234.3167 | fax 802.223.8980 *RGSEnergy.com http://www.rgsenergy.com/ **| william.wh...@rgsenergy.com william.wh...@rgsenergy.com * *Confidentiality Note: *This e-mail message may contain confidential or legally privileged information and is intended only for the use of the intended recipient(s). Any unauthorized disclosure, dissemination, distribution, copying or the taking of any action in reliance on the information herein is prohibited. E-mails are not secure and cannot be guaranteed to be error free as they can be intercepted, amended, or contain viruses. Anyone who communicates with us by e-mail is deemed to have accepted these risks. RGS Energy is not responsible for errors or omissions in this message and denies any responsibility for any damage arising from the use of e-mail. Any opinion and other statement contained in this message and any attachment are solely those of the author and do not necessarily represent those of the company. *From:* RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] *On Behalf Of *Mac Lewis *Sent:* Wednesday, August 27, 2014 8:32 AM *To:* RE-wrenches *Subject:* [RE-wrenches] Rapid shutdown questions Hello wrenches, I am still trying to wrap my head around how to comply with rapid shutdown in off-grid and hybrid situations. I've got a few questions that maybe you can help with. 1. What is a (currently listed) rapid shutdown system that will accommodate 8 strings? I know I can do this with Midnite combiners but as I understand these aren't listed yet. 2. On a remote pole mount, does rapid shutdown apply? If the intent is to isolate a safe zone around an array for fire fighting, it seems as though a standard pole mounted DC disconnect can cover this concern. 3. I estimate on a typical hybrid installation, rapid shutdown will cost at least $3000 to implement. This includes remote shunt trip battery breakers, contactors on PV side of charge controller and roof combiners, and running control cable from remote disconnect to all locations. As of now, this would also require me to modify listed interconnection equipment. Is this what others are finding? 4. AC coupling with microinverters may be the easiest way to comply with most of these requirements. However, this doesn't seem like a great alternative to the standard charge controller installation in an off-grid system. Thanks in advance for your thoughts -- Mac Lewis Yo solo sé que no sé nada. *-Sócrates* ___ 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 -- Mac Lewis *Yo solo sé que no sé nada. -Sócrates* ___ 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] Rapid shutdown questions
That’s correct it’s a manual disconnect and I agree it totally defeats the purpose but some AHJ’s are accepting that it’s within 5’ of entering the building and nowhere in the code does it say it has to be readily accessible. We had one AHJ make us put the disconnect on the side of the house about 15’ feet up. I believe that photo was in the last issue of SolarPro. It was the dumbest thing we’ve ever had to do and it looks ridiculous but that’s what the inspector wanted. From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Mac Lewis Sent: Wednesday, August 27, 2014 10:02 AM To: RE-wrenches Subject: Re: [RE-wrenches] Rapid shutdown questions Hi Will, Yes I'm sure AHJ's will be all over the place for a while here in Colorado. To clarify, is this a manual disconnect in the attic? If so, that is really missing the whole idea of a rapid shutdown. Thanks On Wed, Aug 27, 2014 at 7:47 AM, Will White william.wh...@rgsenergy.commailto:william.wh...@rgsenergy.com wrote: Our experience in MA with rapid shutdown unfortunately varies with AHJ. Some are letting us put an Eaton NEMA 4 disconnect on the roof next to the array. Some are letting us put a disconnect in an accessible attic within 5’ of the penetration. Some are requiring the Midnight Birdhouse remote switch which is expensive. Rapid shutdown doesn’t apply to pole or ground mounts. Hope this helps. Will Will White Operations Manager - New England RGS Energy 64 Main St. |Montpelier, VT 05602 tel 802.223.7804tel:802.223.7804 | mobile 802.234.3167tel:802.234.3167 | fax 802.223.8980tel:802.223.8980 RGSEnergy.comhttp://www.rgsenergy.com/ | william.wh...@rgsenergy.commailto:william.wh...@rgsenergy.com Confidentiality Note: This e-mail message may contain confidential or legally privileged information and is intended only for the use of the intended recipient(s). Any unauthorized disclosure, dissemination, distribution, copying or the taking of any action in reliance on the information herein is prohibited. E-mails are not secure and cannot be guaranteed to be error free as they can be intercepted, amended, or contain viruses. Anyone who communicates with us by e-mail is deemed to have accepted these risks. RGS Energy is not responsible for errors or omissions in this message and denies any responsibility for any damage arising from the use of e-mail. Any opinion and other statement contained in this message and any attachment are solely those of the author and do not necessarily represent those of the company. From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.orgmailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Mac Lewis Sent: Wednesday, August 27, 2014 8:32 AM To: RE-wrenches Subject: [RE-wrenches] Rapid shutdown questions Hello wrenches, I am still trying to wrap my head around how to comply with rapid shutdown in off-grid and hybrid situations. I've got a few questions that maybe you can help with. 1. What is a (currently listed) rapid shutdown system that will accommodate 8 strings? I know I can do this with Midnite combiners but as I understand these aren't listed yet. 2. On a remote pole mount, does rapid shutdown apply? If the intent is to isolate a safe zone around an array for fire fighting, it seems as though a standard pole mounted DC disconnect can cover this concern. 3. I estimate on a typical hybrid installation, rapid shutdown will cost at least $3000 to implement. This includes remote shunt trip battery breakers, contactors on PV side of charge controller and roof combiners, and running control cable from remote disconnect to all locations. As of now, this would also require me to modify listed interconnection equipment. Is this what others are finding? 4. AC coupling with microinverters may be the easiest way to comply with most of these requirements. However, this doesn't seem like a great alternative to the standard charge controller installation in an off-grid system. Thanks in advance for your thoughts -- Mac Lewis Yo solo sé que no sé nada. -Sócrates ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.orgmailto: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.htmhttp://www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.orghttp://www.members.re-wrenches.org -- Mac Lewis Yo solo sé que no sé nada. -Sócrates ___ 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
Re: [RE-wrenches] Rapid shutdown questions
-wrenches] Rapid shutdown questions Hello wrenches, I am still trying to wrap my head around how to comply with rapid shutdown in off-grid and hybrid situations. I've got a few questions that maybe you can help with. 1. What is a (currently listed) rapid shutdown system that will accommodate 8 strings? I know I can do this with Midnite combiners but as I understand these aren't listed yet. 2. On a remote pole mount, does rapid shutdown apply? If the intent is to isolate a safe zone around an array for fire fighting, it seems as though a standard pole mounted DC disconnect can cover this concern. 3. I estimate on a typical hybrid installation, rapid shutdown will cost at least $3000 to implement. This includes remote shunt trip battery breakers, contactors on PV side of charge controller and roof combiners, and running control cable from remote disconnect to all locations. As of now, this would also require me to modify listed interconnection equipment. Is this what others are finding? 4. AC coupling with microinverters may be the easiest way to comply with most of these requirements. However, this doesn't seem like a great alternative to the standard charge controller installation in an off-grid system. Thanks in advance for your thoughts -- Mac Lewis Yo solo sé que no sé nada. *-Sócrates* ___ 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 -- Mac Lewis * Yo solo sé que no sé nada. -Sócrates * ___ 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 ___ 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] Rapid shutdown questions
Hi Mac, all; Since Colorado just adopted NEC2014 July 1, I have not heard any AHJ stories yet. But look at 690.12 (1): Requirements for controlled conductors shall apply only to PV system conductors of more than 5 ft in length inside a building, OR more than 10 ft from a PV array. (my emphasis on OR) I interpret this to mean that if a ground mount array is more than 10 ft from the building, then any PV circuits that run up the outside of the building from their trench (for example to penetrate the wall to the power center on the inside) must be controlled because they are on the building. And even if you penetrated right from the trench into the crawl space, then up to the power center on the inside wall, with less than 5 ft distance, still needs to be controlled if the array is more than 10 feet from the building because of that OR The logic and safety advantage of this for firefighters is another topic entirely. As a first-arriving firefighter, I would spot the PV racks on the ground, walk over to them, and throw the disconnects on the nicely-labeled combiner boxes located within 10 feet of the array. All thoughts appreciated, still puzzling this out. Dan Fink Buckville Energy Otherpower NABCEP / IREC / ISPQ accredited Continuing Education Providers 970.672.4342 ___ 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
