Re: [RE-wrenches] MLSD module level shutdown (Solar Energy Solutions)
Hi Chris, Point taken. However, module level rapid shut down was also implemented for the safety of first responders as well. So regardless of GT or ESS configuration, when the rapid shut down device is initiated, the situation is intrinsically safer for a first responder. I’m not suggesting that there aren’t issues with current 690.12 requirements in regards to actual real life safety, however the RSD is in theory something of value and does do a thing. Kindly, -Chris On Sat, Jan 30, 2021 at 8:47 PM Connell Christopher < connell.christop...@fronius.com> wrote: > Hello Andrew, > > I find your opinion on needing Rapid Shutdown. Critters chewing on wires > is the reason why they implemented article 690.11 of the NEC, arc fault > detection. > > What does module level shut down do? Well mostly nothing, especially in > energy storage systems. In standard grid-tie systems IF the inverter > detects the arc, the inverter will shut down. Most Rapid shutdown solutions > are PLC solutions, so the inverter trips off, and then the voltage gets > reduced to less than 80v within the array boundary (rapid shutdown > activated). 80v is still high enough for a sustainable arc to occur that > can melt MC4s. > > If the same rapid shutdown topology is for an energy storage system, rapid > shutdown won't occur (an inverter error keeps RSD active, due to Energy > storage). So in reality the rapid shutdown devices doesn't do a thing. > > > Sustainable regards, > Chris Connell > > > > > -Original Message- > From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On > Behalf Of re-wrenches-requ...@lists.re-wrenches.org > Sent: Friday, January 29, 2021 4:53 PM > To: re-wrenches@lists.re-wrenches.org > Subject: [GREY] RE-wrenches Digest, Vol 14, Issue 28 > > Send RE-wrenches mailing list submissions to > re-wrenches@lists.re-wrenches.org > > To subscribe or unsubscribe via the World Wide Web, visit > > http://lists.re-wrenches.org/listinfo.cgi/re-wrenches-re-wrenches.org > or, via email, send a message with subject or body 'help' to > re-wrenches-requ...@lists.re-wrenches.org > > You can reach the person managing the list at > re-wrenches-ow...@lists.re-wrenches.org > > When replying, please edit your Subject line so it is more specific than > "Re: Contents of RE-wrenches digest..." > > > When responding to posts within the Digest, be sure to restore the > Subject: line to the original, and please edit out any extraneous lines > from the quoted message. > > > Today's Topics: > >1. MLSD module level shutdown (s...@ecologicalsystems.biz) >2. Re: MLSD module level shutdown (Solar Energy Solutions) >3. Re: MLSD module level shutdown (Kristopher Schmid) >4. Re: MLSD module level shutdown (frenergy) >5. Re: MLSD module level shutdown (Dave Angelini Offgrid Solar) >6. Re: MLSD module level shutdown (Ray) >7. Re: MLSD module level shutdown (Dave Angelini Offgrid Solar) > > > -- > > Message: 1 > Date: Fri, 29 Jan 2021 14:09:48 -0500 > From: s...@ecologicalsystems.biz > To: re-wrenches@lists.re-wrenches.org > Cc: Melissa Ann MacCarthy > Subject: [RE-wrenches] MLSD module level shutdown > Message-ID: > > Content-Type: text/plain; charset=utf-8 > > So far the module level shutdown requirements have been a real blow to our > industry. The reliability and cost from a maintenance and installation > standpoint has been very hit or miss so far. It feels like this requirement > was rolled out far too quickly without enough forethought to its impact on > the industry. We are constantly going out and fixing problems with mlsd > installed by other contractors. Thankfully the problems have nothing to do > with the quality of the installations. The problems are almost all due to > premature failure of the products or some inherent defect in them. This is > a serious issue costing the industry time and resources and making our > installers less safe. It just doesn?t really accomplish the intended goal > of the requirement. > I?m curious how other wrenches are dealing with this issue. I recently > became aware of fixMLSD.com which appears to be focused on bringing a more > sensible approach to this requirement. > > Your thoughts are appreciated, > Sky Sims > Https://EcologicalSystems.biz > ?Just An Old Wrench? > > -- > > Message: 2 > Date: Fri, 29 Jan 2021 19:56:08 + (UTC) > From: Solar Energy Solutions > To: "re-wrenches@lists.re-wrenches.org" > > Cc: Melissa Ann MacCarthy > Subject: Re: [RE-wrenches] MLSD module level shutdown > Message-ID: <536449831.235766.1611950168...@mail.yahoo.com> > Content-Type: text/plain; charset="utf-8" > > Dear All, > I have been an outspoken critic of module level shutdown for all the > reasons folks do.? However, I have come around.? We have witnessed too many > systems where rooftop wiring has been chewed up by critters... mostl
Re: [RE-wrenches] MLSD module level shutdown
Is MLSD required in Europe or other parts of the world? What is their track record for safety? --- On 2021-01-29 14:09, s...@ecologicalsystems.biz wrote: So far the module level shutdown requirements have been a real blow to our industry. The reliability and cost from a maintenance and installation standpoint has been very hit or miss so far. It feels like this requirement was rolled out far too quickly without enough forethought to its impact on the industry. We are constantly going out and fixing problems with mlsd installed by other contractors. Thankfully the problems have nothing to do with the quality of the installations. The problems are almost all due to premature failure of the products or some inherent defect in them. This is a serious issue costing the industry time and resources and making our installers less safe. It just doesn’t really accomplish the intended goal of the requirement. I’m curious how other wrenches are dealing with this issue. I recently became aware of fixMLSD.com which appears to be focused on bringing a more sensible approach to this requirement. Your thoughts are appreciated, Sky Sims Https://EcologicalSystems.biz “Just An Old Wrench” ___ 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 There are two list archives for searching. When one doesn't work, try the other: https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: http://www.re-wrenches.org/etiquette.htm Check out or update participant bios: http://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 There are two list archives for searching. When one doesn't work, try the other: https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: http://www.re-wrenches.org/etiquette.htm Check out or update participant bios: http://www.members.re-wrenches.org
Re: [RE-wrenches] MLSD module level shutdown (Solar Energy Solutions)
Hello Andrew, I find your opinion on needing Rapid Shutdown. Critters chewing on wires is the reason why they implemented article 690.11 of the NEC, arc fault detection. What does module level shut down do? Well mostly nothing, especially in energy storage systems. In standard grid-tie systems IF the inverter detects the arc, the inverter will shut down. Most Rapid shutdown solutions are PLC solutions, so the inverter trips off, and then the voltage gets reduced to less than 80v within the array boundary (rapid shutdown activated). 80v is still high enough for a sustainable arc to occur that can melt MC4s. If the same rapid shutdown topology is for an energy storage system, rapid shutdown won't occur (an inverter error keeps RSD active, due to Energy storage). So in reality the rapid shutdown devices doesn't do a thing. Sustainable regards, Chris Connell -Original Message- From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of re-wrenches-requ...@lists.re-wrenches.org Sent: Friday, January 29, 2021 4:53 PM To: re-wrenches@lists.re-wrenches.org Subject: [GREY] RE-wrenches Digest, Vol 14, Issue 28 Send RE-wrenches mailing list submissions to re-wrenches@lists.re-wrenches.org To subscribe or unsubscribe via the World Wide Web, visit http://lists.re-wrenches.org/listinfo.cgi/re-wrenches-re-wrenches.org or, via email, send a message with subject or body 'help' to re-wrenches-requ...@lists.re-wrenches.org You can reach the person managing the list at re-wrenches-ow...@lists.re-wrenches.org When replying, please edit your Subject line so it is more specific than "Re: Contents of RE-wrenches digest..." When responding to posts within the Digest, be sure to restore the Subject: line to the original, and please edit out any extraneous lines from the quoted message. Today's Topics: 1. MLSD module level shutdown (s...@ecologicalsystems.biz) 2. Re: MLSD module level shutdown (Solar Energy Solutions) 3. Re: MLSD module level shutdown (Kristopher Schmid) 4. Re: MLSD module level shutdown (frenergy) 5. Re: MLSD module level shutdown (Dave Angelini Offgrid Solar) 6. Re: MLSD module level shutdown (Ray) 7. Re: MLSD module level shutdown (Dave Angelini Offgrid Solar) -- Message: 1 Date: Fri, 29 Jan 2021 14:09:48 -0500 From: s...@ecologicalsystems.biz To: re-wrenches@lists.re-wrenches.org Cc: Melissa Ann MacCarthy Subject: [RE-wrenches] MLSD module level shutdown Message-ID: Content-Type: text/plain; charset=utf-8 So far the module level shutdown requirements have been a real blow to our industry. The reliability and cost from a maintenance and installation standpoint has been very hit or miss so far. It feels like this requirement was rolled out far too quickly without enough forethought to its impact on the industry. We are constantly going out and fixing problems with mlsd installed by other contractors. Thankfully the problems have nothing to do with the quality of the installations. The problems are almost all due to premature failure of the products or some inherent defect in them. This is a serious issue costing the industry time and resources and making our installers less safe. It just doesn?t really accomplish the intended goal of the requirement. I?m curious how other wrenches are dealing with this issue. I recently became aware of fixMLSD.com which appears to be focused on bringing a more sensible approach to this requirement. Your thoughts are appreciated, Sky Sims Https://EcologicalSystems.biz ?Just An Old Wrench? -- Message: 2 Date: Fri, 29 Jan 2021 19:56:08 + (UTC) From: Solar Energy Solutions To: "re-wrenches@lists.re-wrenches.org" Cc: Melissa Ann MacCarthy Subject: Re: [RE-wrenches] MLSD module level shutdown Message-ID: <536449831.235766.1611950168...@mail.yahoo.com> Content-Type: text/plain; charset="utf-8" Dear All, I have been an outspoken critic of module level shutdown for all the reasons folks do.? However, I have come around.? We have witnessed too many systems where rooftop wiring has been chewed up by critters... mostly squirrels.? We have seen everything from residential fires to holes in metal roofs caused by a DC arc.?? I never thought I would see the day when I would not only be thinking MLSD is a good idea but advocating for it. Smiles, ?Andrew KoyaanisqatsiPresidentSolar Energy Solutions, Inc. The BRIGHT CHOICE Since 1987, helping you and your Portland neighbors move towards an environmentally sustainable future.503-238-4502 www.SolarEnergyOregon.com On Friday, January 29, 2021, 11:25:28 AM PST, s...@ecologicalsystems.biz wrote: So far the module level shutdown requirements have been a real blow to our industry. The reliability and cost from a maintenance and installation standpoint has been very hit or miss so
