Re: [RE-wrenches] off grid PV connected to generator
Eric, Good questions, and you hit on a number of topics so let me see if I can address them one at a time, not necessarily in chronological order. Yes, the optimal application for the GTFX / GVFX inverter series is grid tie with battery backup. If you just want backup to the grid, the traditional FX is a great solution. If you need extended run-time and want to integrate a generator, then the Radian series is a better solution because it can not only integrate both grid and generator, but it can change its operating parameters based on which input it's connected to. The SW, XW and Radian inverters are all capable of operating on-grid (grid-interactive or backup) or off-grid (with or without a generator). However, none will automatically disconnect the PV when the genny auto-starts, nor would I suggest that they should. Realistically, the system should only start the genny when the batteries are near depletion -- if it's started, the batteries need all the help they can get. Rather, the generator should only be disconnected (turned off) when the batteries reach the absorb setpoint. BTW, I can't speak for everyone but none of those inverters have that functionality, at least not yet. With 600 Watts of connected PV, I wouldn't worry about disconnecting the PV. Even with a small battery bank, the sun will set before that size of array drives the bank anywhere close to an absorb voltage. Add another zero to the PV size and my answer would be different, of course. Also, if you do wind up installing an automatic transfer switch with a battery-based inverter system, don't allow the ATS to control the generator starting, even if that flies against every tradition of the generator sales guy. You don't want the genny running through every minute of the power outage, you want the system to start the genny only when the batteries are low. Good luck with it, and enjoy the sun! Phil On Tue, Jan 15, 2013 at 1:50 PM, SunHarvest wrote: > Further, I recently installed a GVFX for a customer. I'm hearing from > certain sources that the grid-tied line of inverters from Outback are not > designed to interface with a generator. Really?? > > I was told by Outback to install a transfer switch line/supply side of the > inverter; that this was the only way to interface the genny with the > inverter; that the AC Hot In could come from grid or a genset. And indeed, > this is the only way I can figure out how to get the genny to charge the > batteries when the grid goes down. But then again, I don't have the > extensive electrical background that allows me to think outside the box as > often as I would like...that's why I'm posing my query here for the pros. > In this Outback install I have to again advise the homeowner to open the PV > breaker to the inverter during generator operation, right? Even though he > has a modest 600W (STC) array and an 8.5kW Kohler genset. Hardly the > opportunity for solar to feed back to the genny under the most sunny and > cool of days. I'm more concerned with the Enphase install. > > The Xantrex SW series inverters are fully capable of operating on-grid or > off-grid with a genset. So do those inverters automatically disconnect the > PV when the genny auto-starts? And with the Outback, is the Mate supposed > to do the same (as long as the genny is operated by the auto-start and not > a transfer switch)? > ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] off grid PV connected to generator
one of my biggest gripes about the outback fx series is only one ac input... this was a major step backwards from its trace sw series predecessor. if someone is going to want battery back up on a grid tied system, they surely are going to want the ability to back that up with a generator. the radian series seems to have resolved this. so yes, the fx can sync with a generator, but you need a transfer switch upstream from the single ac input as well as the nerdyness to be able to change the inverter's ac input selection from 'grid' to 'gen' in the mate. this will disable the inverter from trying to sell to the generator. unfortunately this does not relax the ac input requirements the inverter wants to see to enable selling... so your generator better be very clean (inverter generators are best). there is also the 'dt kludge': send the 120 volt ac generator output to a 2:1 transformer (like a 120/240 step up/down). this takes the 120 vac down to around 60 vac -> full wave bridge rectifer -> circuit breaker -> mx 60 -> circuit breaker -> battery. expensive, but a great solution imo. todd On Tuesday, January 15, 2013 1:50pm, "SunHarvest" said: > Further, I recently installed a GVFX for a customer. I'm hearing from > certain sources that the grid-tied line of inverters from Outback are not > designed to interface with a generator. Really?? > > I was told by Outback to install a transfer switch line/supply side of the > inverter; that this was the only way to interface the genny with the > inverter; that the AC Hot In could come from grid or a genset. And indeed, > this is the only way I can figure out how to get the genny to charge the > batteries when the grid goes down. But then again, I don't have the > extensive electrical background that allows me to think outside the box as > often as I would like...that's why I'm posing my query here for the pros. In > this Outback install I have to again advise the homeowner to open the PV > breaker to the inverter during generator operation, right? Even though he > has a modest 600W (STC) array and an 8.5kW Kohler genset. Hardly the > opportunity for solar to feed back to the genny under the most sunny and > cool of days. I'm more concerned with the Enphase install. > > The Xantrex SW series inverters are fully capable of operating on-grid or > off-grid with a genset. So do those inverters automatically disconnect the > PV when the genny auto-starts? And with the Outback, is the Mate supposed to > do the same (as long as the genny is operated by the auto-start and not a > transfer switch)? > > Eric > SunHarvest > > ___ > 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 > > Sent from Finest Planet WebMail. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] off grid PV connected to generator
Hi Dan Would like to know what they suggested besides changing it to a VFX? Jay Peltz power Sent from my iPad On Jan 15, 2013, at 1:54 PM, Dan Fink wrote: > Talk to Outback. It's an easy fix, on-site. > -- > Dan Fink, > Executive Director; > Otherpower > Buckville Energy Consulting > Buckville Publications LLC > NABCEP / IREC accredited Continuing Education Providers > 970.672.4342 (voicemail) > > > On Tue, Jan 15, 2013 at 2:50 PM, SunHarvest wrote: > (snip) >> Further, I recently installed a GVFX for a customer. I'm hearing from >> certain sources that the grid-tied line of inverters from Outback are not >> designed to interface with a generator. Really?? > (snip) > > > > > > > ___ > 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
Re: [RE-wrenches] off grid PV connected to generator
I did. They were less than helpful. At least the two or three different techs I talked to. They sounded as green as me. - Original Message - From: Dan Fink To: RE-wrenches Sent: Tuesday, January 15, 2013 1:54 PM Subject: Re: [RE-wrenches] off grid PV connected to generator Talk to Outback. It's an easy fix, on-site. -- Dan Fink, Executive Director; Otherpower Buckville Energy Consulting Buckville Publications LLC NABCEP / IREC accredited Continuing Education Providers 970.672.4342 (voicemail) On Tue, Jan 15, 2013 at 2:50 PM, SunHarvest wrote: (snip) Further, I recently installed a GVFX for a customer. I'm hearing from certain sources that the grid-tied line of inverters from Outback are not designed to interface with a generator. Really?? (snip) -- ___ 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
Re: [RE-wrenches] Sanyo HIP-200BA3 defect
Yes we have had the exact problem. Sanyo/Pnansonic has refused to replace the module which clearly has a problem. Sanyo/Panasonic is not an honorable company. Wayne Irwin, EE Director of Engineering Pure Energy Solar International Inc. State Licensed Solar Contractor License # CVC56695 wa...@pureenergysolar.com http://PureEnergySolar.com 352 377-6527 Office 352 336-3299 Fax The content of this message is Pure Energy Solar Confidential. If you are not the intended recipient and have received this message in error, any use or distribution is prohibited. Please notify me immediately by reply e-mail and delete this message from your computer system. Thank you. Date: Tue, 15 Jan 2013 14:03:24 -0700 From: danbo...@gmail.com To: re-wrenches@lists.re-wrenches.org Subject: Re: [RE-wrenches] Sanyo HIP-200BA3 defect No problems here, Larry. In fact I'm still looking for one of those modules to expand a small off-grid system. -- Dan Fink, Executive Director; Otherpower Buckville Energy Consulting Buckville Publications LLC NABCEP / IREC accredited Continuing Education Providers 970.672.4342 (voicemail) On Tue, Jan 15, 2013 at 1:59 PM, Larry Crutcher, Starlight Solar Power Systems wrote: Wrenches, Has anyone had Sanyo BA3 module defects? (see attached picture) I have been trying to contact Sanyo support at 408-861-8404 but it is always busy. Anyone have other contact name or phone? Thank you, Larry Crutcher Starlight Solar Power Systems (928) 342-9103 ___ 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
Re: [RE-wrenches] off grid PV connected to generator
Talk to Outback. It's an easy fix, on-site. -- Dan Fink, Executive Director; Otherpower Buckville Energy Consulting Buckville Publications LLC NABCEP / IREC accredited Continuing Education Providers 970.672.4342 (voicemail) On Tue, Jan 15, 2013 at 2:50 PM, SunHarvest wrote: (snip) > Further, I recently installed a GVFX for a customer. I'm hearing from > certain sources that the grid-tied line of inverters from Outback are not > designed to interface with a generator. Really?? (snip) ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
[RE-wrenches] off grid PV connected to generator
I'm a bit confused by this thread and am looking for some clarity. To that end here's an example of a recent installation we completed (under the direction of a licensed electrician, not me (praise the Lord)): Grid & Genset feed Main Panel (genny on ATS) ---> Main panel feeding subpanel ---> subpanel is point of connection for our PV array with Enphase. My understanding is that the inverters will look for an "infinite grid" and sensing none when the grid goes down but instead sensing the genset power, the inverters will not turn on. So, we should have tied the PV system to the main panel, that's what I'm reading from the conversation. This would have been completely cost prohibitive due to trench length. Now should we advise the customer to manually open the PV breakers in the subpanel to be safe? This is what I'm reading from the conversation. Further, I recently installed a GVFX for a customer. I'm hearing from certain sources that the grid-tied line of inverters from Outback are not designed to interface with a generator. Really?? I was told by Outback to install a transfer switch line/supply side of the inverter; that this was the only way to interface the genny with the inverter; that the AC Hot In could come from grid or a genset. And indeed, this is the only way I can figure out how to get the genny to charge the batteries when the grid goes down. But then again, I don't have the extensive electrical background that allows me to think outside the box as often as I would like...that's why I'm posing my query here for the pros. In this Outback install I have to again advise the homeowner to open the PV breaker to the inverter during generator operation, right? Even though he has a modest 600W (STC) array and an 8.5kW Kohler genset. Hardly the opportunity for solar to feed back to the genny under the most sunny and cool of days. I'm more concerned with the Enphase install. The Xantrex SW series inverters are fully capable of operating on-grid or off-grid with a genset. So do those inverters automatically disconnect the PV when the genny auto-starts? And with the Outback, is the Mate supposed to do the same (as long as the genny is operated by the auto-start and not a transfer switch)? Eric SunHarvest ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Sanyo HIP-200BA3 defect
No problems here, Larry. In fact I'm still looking for one of those modules to expand a small off-grid system. -- Dan Fink, Executive Director; Otherpower Buckville Energy Consulting Buckville Publications LLC NABCEP / IREC accredited Continuing Education Providers 970.672.4342 (voicemail) On Tue, Jan 15, 2013 at 1:59 PM, Larry Crutcher, Starlight Solar Power Systems wrote: > Wrenches, > > Has anyone had Sanyo BA3 module defects? (see attached picture) > > I have been trying to contact Sanyo support at 408-861-8404 but it is > always busy. Anyone have other contact name or phone? > > > Thank you, > > Larry Crutcher > Starlight Solar Power Systems > (928) 342-9103 > > > ___ > 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
Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules
Hi August, I maintain that the WEEB is an irreversible splice. If you want to disconnect a WEEB from a structure, you must irreversibly damage the device. It cannot be reused. Admittedly the force required to remove a WEEB is less than that required for a thermal splice, but it doesn't take much force to just cut a wire either. I would argue that the intent of the code is to prevent inadvertent removal of the ground. You must knowingly remove a WEEB from the grounding path and if you do so in the maintenance of an array, good workmanship requires that you restore the connection. Best Regards, Brian Wiley On 1/15/2013 2:11 PM, August Goers wrote: Hi John, I definitely see your point and that is why I was somewhat questioning the use of WEEBs with Enphase below. Enphases's instructions (link posted in thread below) seem to indicate a support of running the continuous GEC on the rack and then bonding the microinverter to the rack with WEEBs. Maybe I am misinterpreting the document or perhaps Enphase has another take. There is no question that according to NEC 250.64(C) the GEC must be continuous. In the 2008 NEC handbook section 690.42 Point of System Grounding Connection has an application note "Connections are to be made in accordance with markings on the equipment or in the installation instructions." All that said, it seems like technology is leaning towards listed AC Modules or floating array inverters. It sounds like that removes the requirement for a GEC which is great to help reduce installation costs. The GEC has always been a pain in the neck. Best, August -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of John Berdner Sent: Monday, January 14, 2013 7:07 PM To: RE-wrenches Subject: Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules August: The WEEB or other Listed grounding means between the inverter case and the structure are not "contiguous or irreversible spliced" and therefore do not meet the requirements for a GEC. If the structure is then grounded via a bolt on lug it also is not irreversible or contiguous. If you can unbolt something and disconnect the ground then it is not contiguous or irreversibly spliced. Both of the above are ok for EGC but not for GEC. GEC is a pain in the neck but the Code requirements are clear. If the PV array conductor (pos or neg) is bonded to ground by the inverter then the inverter requires a GEC with all the related requirements - no if and's or but's. Best Regards, John Berdner General Manager, North America SolarEdge Technologies, Inc. 3347 Gateway Boulevard, Fremont CA 94538 USA (*Please note of our new address.) T: 510.498.3201 ext 747 M: 530.277.4894 -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of August Goers Sent: Monday, January 14, 2013 4:32 PM To: RE-wrenches Subject: Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules Hi Mark, There have been some recent threads on this list touching on this topic. As far as I understand, Enphase microinvertes still require a GEC up to and including the 2011 NEC. I don't know about the 2014 NEC. Enphase bonds the positive DC module conductor to ground. Pages 16 and 17 of their M215 installation manual address grounding: http://enphase.com/wp-uploads/enphase.com/2011/06/Enphase_M215_Installatio nOperation_Manual.pdf Products such as Solar Bridge that are listed as Alternating Current (AC) Modules (per NEC 690.2) don't need a Grounding Electrode Conductor (GEC) as long as there are no conductors connected to ground within the product. Solar Bridge has a good article on this: http://solarbridgetech.com/microinverters-and-ac-pv-modules-are-different/ This all takes us back to using Enphase with grounding washers like WEEBs for the GEC. According to what I read in their instructions (and after many phone calls), it sounds like they are okay with us running the GEC on the racking in #6 and then bonding the microinverters to the rack with WEEBs. Seems a little strange but it's been working for us. Good topic! Best, August 415.559.1525 -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Mark Frye Sent: Monday, January 14, 2013 3:31 PM To: RE-wrenches Subject: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules Does anyone have the latest on the GEC for micro-inverters/ACPV issue? I know it is still in NEC 2008 and I believe 2011 with plans to address it in 2014. I am specifically interested in the issue of GEC means continues (irreversible splices) and the whole business of the DC side of these devices constituting a separately derived system. Enphase technical support is fine if the micro inverter chasis is bonded to a EGC only, but they leave the lug on the chasis if you want/need to build a GEC.
[RE-wrenches] Sanyo HIP-200BA3 defect
Wrenches, Has anyone had Sanyo BA3 module defects? (see attached picture) I have been trying to contact Sanyo support at 408-861-8404 but it is always busy. Anyone have other contact name or phone? Thank you, Larry Crutcher Starlight Solar Power Systems (928) 342-9103 <>___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules
August: Yes, the entire GEC requirement is a pain in the neck and IMHO makes no sense for grid tied PV. Historically it comes out of the rural electrification days when you had DC systems actually "supplying premises wiring", i.e. lighting circuits, outlets, etc. In that context the bond between the DC circuit conductors and Ground is a critical conductor just as it is in an AC system supplying premises wiring. If you lose the ground reference in one of these systems then the voltage on the circuit conductors can float all over the place and bad things can happen. (think loose neutral in a split phase AC system). The Code requirements for a GEC are restrictive precisely to assure the integrity of the bond to ground. I have long contended that grid tied PV systems do not supply premises wiring and so the GEC requirement does not even apply. Others in high places disagree. No matter... the industry moving to ungrounded systems which eliminate the need in another way. This is but one of many reasons I like ungrounded arrays. Best Regards, John Berdner General Manager, North America SolarEdge Technologies, Inc. 3347 Gateway Boulevard, Fremont CA 94538 USA (*Please note of our new address.) T: 510.498.3201 ext 747 M: 530.277.4894 -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of August Goers Sent: Tuesday, January 15, 2013 11:12 AM To: RE-wrenches Subject: Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules Hi John, I definitely see your point and that is why I was somewhat questioning the use of WEEBs with Enphase below. Enphases's instructions (link posted in thread below) seem to indicate a support of running the continuous GEC on the rack and then bonding the microinverter to the rack with WEEBs. Maybe I am misinterpreting the document or perhaps Enphase has another take. There is no question that according to NEC 250.64(C) the GEC must be continuous. In the 2008 NEC handbook section 690.42 Point of System Grounding Connection has an application note "Connections are to be made in accordance with markings on the equipment or in the installation instructions." All that said, it seems like technology is leaning towards listed AC Modules or floating array inverters. It sounds like that removes the requirement for a GEC which is great to help reduce installation costs. The GEC has always been a pain in the neck. Best, August -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of John Berdner Sent: Monday, January 14, 2013 7:07 PM To: RE-wrenches Subject: Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules August: The WEEB or other Listed grounding means between the inverter case and the structure are not "contiguous or irreversible spliced" and therefore do not meet the requirements for a GEC. If the structure is then grounded via a bolt on lug it also is not irreversible or contiguous. If you can unbolt something and disconnect the ground then it is not contiguous or irreversibly spliced. Both of the above are ok for EGC but not for GEC. GEC is a pain in the neck but the Code requirements are clear. If the PV array conductor (pos or neg) is bonded to ground by the inverter then the inverter requires a GEC with all the related requirements - no if and's or but's. Best Regards, John Berdner General Manager, North America SolarEdge Technologies, Inc. 3347 Gateway Boulevard, Fremont CA 94538 USA (*Please note of our new address.) T: 510.498.3201 ext 747 M: 530.277.4894 -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of August Goers Sent: Monday, January 14, 2013 4:32 PM To: RE-wrenches Subject: Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules Hi Mark, There have been some recent threads on this list touching on this topic. As far as I understand, Enphase microinvertes still require a GEC up to and including the 2011 NEC. I don't know about the 2014 NEC. Enphase bonds the positive DC module conductor to ground. Pages 16 and 17 of their M215 installation manual address grounding: http://enphase.com/wp-uploads/enphase.com/2011/06/Enphase_M215_Installatio nOperation_Manual.pdf Products such as Solar Bridge that are listed as Alternating Current (AC) Modules (per NEC 690.2) don't need a Grounding Electrode Conductor (GEC) as long as there are no conductors connected to ground within the product. Solar Bridge has a good article on this: http://solarbridgetech.com/microinverters-and-ac-pv-modules-are-different/ This all takes us back to using Enphase with grounding washers like WEEBs for the GEC. According to what I read in their instructions (and after many phone calls), it sounds like they are okay with us running the GEC on the racking in #6 and then bonding the microinverte
Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules
Hi John, I definitely see your point and that is why I was somewhat questioning the use of WEEBs with Enphase below. Enphases's instructions (link posted in thread below) seem to indicate a support of running the continuous GEC on the rack and then bonding the microinverter to the rack with WEEBs. Maybe I am misinterpreting the document or perhaps Enphase has another take. There is no question that according to NEC 250.64(C) the GEC must be continuous. In the 2008 NEC handbook section 690.42 Point of System Grounding Connection has an application note "Connections are to be made in accordance with markings on the equipment or in the installation instructions." All that said, it seems like technology is leaning towards listed AC Modules or floating array inverters. It sounds like that removes the requirement for a GEC which is great to help reduce installation costs. The GEC has always been a pain in the neck. Best, August -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of John Berdner Sent: Monday, January 14, 2013 7:07 PM To: RE-wrenches Subject: Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules August: The WEEB or other Listed grounding means between the inverter case and the structure are not "contiguous or irreversible spliced" and therefore do not meet the requirements for a GEC. If the structure is then grounded via a bolt on lug it also is not irreversible or contiguous. If you can unbolt something and disconnect the ground then it is not contiguous or irreversibly spliced. Both of the above are ok for EGC but not for GEC. GEC is a pain in the neck but the Code requirements are clear. If the PV array conductor (pos or neg) is bonded to ground by the inverter then the inverter requires a GEC with all the related requirements - no if and's or but's. Best Regards, John Berdner General Manager, North America SolarEdge Technologies, Inc. 3347 Gateway Boulevard, Fremont CA 94538 USA (*Please note of our new address.) T: 510.498.3201 ext 747 M: 530.277.4894 -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of August Goers Sent: Monday, January 14, 2013 4:32 PM To: RE-wrenches Subject: Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules Hi Mark, There have been some recent threads on this list touching on this topic. As far as I understand, Enphase microinvertes still require a GEC up to and including the 2011 NEC. I don't know about the 2014 NEC. Enphase bonds the positive DC module conductor to ground. Pages 16 and 17 of their M215 installation manual address grounding: http://enphase.com/wp-uploads/enphase.com/2011/06/Enphase_M215_Installatio nOperation_Manual.pdf Products such as Solar Bridge that are listed as Alternating Current (AC) Modules (per NEC 690.2) don't need a Grounding Electrode Conductor (GEC) as long as there are no conductors connected to ground within the product. Solar Bridge has a good article on this: http://solarbridgetech.com/microinverters-and-ac-pv-modules-are-different/ This all takes us back to using Enphase with grounding washers like WEEBs for the GEC. According to what I read in their instructions (and after many phone calls), it sounds like they are okay with us running the GEC on the racking in #6 and then bonding the microinverters to the rack with WEEBs. Seems a little strange but it's been working for us. Good topic! Best, August 415.559.1525 -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Mark Frye Sent: Monday, January 14, 2013 3:31 PM To: RE-wrenches Subject: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules Does anyone have the latest on the GEC for micro-inverters/ACPV issue? I know it is still in NEC 2008 and I believe 2011 with plans to address it in 2014. I am specifically interested in the issue of GEC means continues (irreversible splices) and the whole business of the DC side of these devices constituting a separately derived system. Enphase technical support is fine if the micro inverter chasis is bonded to a EGC only, but they leave the lug on the chasis if you want/need to build a GEC. SolarBridge (pre-assembled micro-inverter) seems to be devoid of a chasis lug and therefore by extension does not/can not had a GEC in the system. Exeltech (integrated micro-inverter aka. ACPV) does not seem to have a lug on its chasis. Has the industry pretty much moved to not requiring a GEC for these devices and if so, how are the AHJ taking it? Thanks, Mark Frye Berkeley Solar Electric Systems ___ 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.or
[RE-wrenches] SMA micro inverter
If memory serves, it's been 2-3 years since our SMA friends starting teasing us with their new micro inverter. Yet as far as I know, they're still not shipping these buggers..unless someone knows differently. Does anyone out there know what's going on with the SMA micros at this point? I can't remember any other RE product being advertised for this long without actually seeing the light of day. And this from the no. 1 inverter manufacturer in the world? Strange.. Thanks, marco ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules
Mark: I don't know the SolarBridge product as well as some others. Like you, I would ASS U ME the lack of a grounding lug would indicate that a GEC is not needed. Referring to the manufactures written instructions on grounding in the manual is always the best reference. You are correct, there are 2 cases where you would not need a GEC per Code. 1) The unit is Listed as an AC Module so it is exempt from DC side requirements. This is not to be confused with a micro-inverter installed in the field on a module which would still need to meet the DC side requirements. 2) The inverter operates with a floating array, i.e. the array positive or negative (or neutral in a bi-polar array) are not bonded to ground. Just to clarify one point ... With a floating array the inverter topology could be either isolated (HF or LF transformer) or non-isolated (transformerless). The main criteria is if array conductors are, or are not, bonded to ground by the inverter (which is not necessarily related to a specific topology). Best Regards, John Berdner General Manager, North America SolarEdge Technologies, Inc. 3347 Gateway Boulevard, Fremont CA 94538 USA (*Please note of our new address.) T: 510.498.3201 ext 747 M: 530.277.4894 -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Mark Frye Sent: Monday, January 14, 2013 8:11 PM To: RE-wrenches Subject: Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules I am interested in the SolarBridge , it has no chasis lug so it must not require a GEC, right? So why does it not require a GEC? Is it because it is not an isolated inverter? Because it is an isolated inverter that does not have a grounded current carrying conductor on the DC side? Because it is listed as an AC module so who cares what is happening on the DC side? On 1/14/2013 6:52 PM, John Berdner wrote: > Mark: > > The GEC is required if the inverter bonds one of the PV conductors to ground > (as Enphase does). > Enphase support may not have a problem with it but not using a GEC (with all > the GEC requirements) on any system with a grounded array is definitely a > Code violation in NEC 2008 and 2011. > I don't recall it being eliminated in the 2014 Code either but could be wrong. > > If the inverter does not bond the array positive or array negative to ground > then the array is ungrounded so no GEC is required. > Non-isolated inverters (also referred to as transformerless inverters) do not > bond the array negative or array positive to ground and so no GEC is required > (EGC is still required). > > If you have a Listed AC module then none of the DC side requirements apply so > no GEC would be required unless required by the manufacturer's instructions. > Unfortunately, adding a micro-inverter to a module in the field does not make > it a Listed ac module. > > Best Regards, > > John Berdner > General Manager, North America > > SolarEdge Technologies, Inc. > 3347 Gateway Boulevard, Fremont CA 94538 USA (*Please note of our new > address.) > T: 510.498.3201 ext 747 > M: 530.277.4894 > > > -Original Message- > From: re-wrenches-boun...@lists.re-wrenches.org > [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Mark > Frye > Sent: Monday, January 14, 2013 3:31 PM > To: RE-wrenches > Subject: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules > > Does anyone have the latest on the GEC for micro-inverters/ACPV issue? > > I know it is still in NEC 2008 and I believe 2011 with plans to address it in > 2014. > > I am specifically interested in the issue of GEC means continues > (irreversible splices) and the whole business of the DC side of these devices > constituting a separately derived system. > > Enphase technical support is fine if the micro inverter chasis is bonded to a > EGC only, but they leave the lug on the chasis if you want/need to build a > GEC. > > SolarBridge (pre-assembled micro-inverter) seems to be devoid of a chasis lug > and therefore by extension does not/can not had a GEC in the system. > > Exeltech (integrated micro-inverter aka. ACPV) does not seem to have a lug on > its chasis. > > Has the industry pretty much moved to not requiring a GEC for these devices > and if so, how are the AHJ taking it? > > Thanks, > Mark Frye > Berkeley Solar Electric Systems > ___ > 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 > > > 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
Re: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules
Hello Mark (and all), Exeltech AC Module inverters do not have an external ground connection because they are certified to UL1741 as grounded through the utility ground. Also, and because all DC wiring is internal to the inverter, there is no requirement for DC ground-fault or arc-fault circuitry in our inverters. Installers don't need to attach a ground conductor to our inverters. That step has already been done internally for you. To attain this certification, and as part of the certification to UL1741, our inverters had to conduct 40 amps through the chassis and inverter wiring without damage or destruction to the conductors and connectors. Dan Lepinski, Senior Engineer Exeltech / Exeltech Solar Products --- On Mon, 1/14/13, Mark Frye wrote: > From: Mark Frye > Subject: [RE-wrenches] GEC for Micro-Inverters and ACPV Modules > To: "RE-wrenches" > Date: Monday, January 14, 2013, 5:31 PM > Does anyone have the latest on the > GEC for micro-inverters/ACPV issue? > > I know it is still in NEC 2008 and I believe 2011 with plans > to address it in 2014. > > I am specifically interested in the issue of GEC means > continues (irreversible splices) and the whole business of > the DC side of these devices constituting a separately > derived system. > > Enphase technical support is fine if the micro inverter > chasis is bonded to a EGC only, but they leave the lug on > the chasis if you want/need to build a GEC. > > SolarBridge (pre-assembled micro-inverter) seems to be > devoid of a chasis lug and therefore by extension does > not/can not had a GEC in the system. > > Exeltech (integrated micro-inverter aka. ACPV) does not seem > to have a lug on its chasis. > > Has the industry pretty much moved to not requiring a GEC > for these devices and if so, how are the AHJ taking it? > > Thanks, > Mark Frye > Berkeley Solar Electric Systems > ___ > 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
