Re: [RE-wrenches] GEC sizing for a high amp, low voltage PV system with microinverters
Hi Bill and wrenches, To clarify, our new Enphase M250 microinverter does not have a grounding terminal. The grounding of the M250 will be provided through the Engage cable. We only have a hole in the lid, in the rare case that a lug will be desired or required by the AHJ, but we do not provide the grounding clip with the microinverter. A grounding terminal can be added to the microinverter. We have an application note on alternate grounding methods for the M250, if needed. On Wed, Sep 18, 2013 at 9:37 AM, Bill Brooks billbroo...@yahoo.com wrote: Dave, Gary, and Charlie, ** ** First, the directions from the manufacturer should be the guide as to whether a GEC is required or not. Just because a GEC terminal is located on the equipment, does not mean that one is required. Case in point—Enphase’s new IG product does not require a GEC, yet it has a grounding terminal for AHJs that might insist on one. This terminal is not intended for a GEC, but it is intended for an extra EGC if the AHJ requires it (LOL on all the abbreviations). ** ** The 2014 NEC makes it very clear that ungrounded PV systems do NOT require an GEC on the dc side and that the ac EGC is sufficient to provide a ground reference for the required dc EGC. ** ** “690.47(B) *Direct-Current Systems.* …*An ac equipment grounding system shall be permitted to be used for equipment grounding of inverters and other equipment and for the ground-fault detection reference for ungrounded PV systems.* ** ** “690.47(C)(3) *Combined Direct-Current Grounding Electrode Conductor and Alternating-Current Equipment* *Grounding Conductor.** An unspliced, or irreversibly spliced, combined grounding conductor shall be run from* *the marked dc grounding electrode conductor connection point along with the ac circuit conductors to the grounding* *busbar in the associated ac equipment. This combined grounding conductor shall be the larger of the sizes specified* *by 250.122 or 250.166 and shall be installed in accordance with 250.64(E).* *For ungrounded systems, this conductor shall be sized in accordance with 250.122 and shall not be required to be larger than the largest ungrounded phase conductor.**”* * * Red letters not Jesus’ words. This is the new language of the 2014 NEC. It is now in print. ** ** The very practical reason that a 6AWG is only required with a single ground rod has to do with the current carrying capacity of a 5/8”, 8’ ground rod in soils of low resistivity—nothing more. ** ** Bill. ** ** ** ** *From:* re-wrenches-boun...@lists.re-wrenches.org [mailto: re-wrenches-boun...@lists.re-wrenches.org] *On Behalf Of *Dave Click *Sent:* Wednesday, September 18, 2013 5:38 AM *To:* re-wrenches@lists.re-wrenches.org *Subject:* Re: [RE-wrenches] GEC sizing for a high amp, low voltage PV system with microinverters ** ** I think Gary may be overthinking this. If the micro-inverters have a GEC lug then you'll need to run a GEC. If you run your GEC to a ground rod, then you don't need to use one larger than #6 per 250.166(C). (note also (D) and (E) but they're less useful to you here) * Commentary:* It makes no sense to me why the NEC can require a 0.9in diameter, #600mcm GEC for some systems (not this one) per 250.166(B) and then say oh wait, you installed a single ground rod? Then a #6 is all you need! in 250.166(C). But it certainly makes our lives easier. If the building GE is not a ground rod, you could still run your #6 GEC to that new ground rod, and then bond that rod to the existing electrode using whatever size jumper is required per 250.53 (which I believe would also be a #6). This lets you keep that 300' run as a #6 rather than a #4 or #2 that may be required otherwise. DKC On 2013/9/17 23:56, Gary Willett wrote: Charlie: The answer depends on whether the system (modules and micro-inverters) is grounded or ungrounded. I think you are describing a grounded system, but it's not totally clear based on your issue description. If the micro-inverter is transformer-less the conductors are not isolated between the DC-in and the AC-out. This requires the micro-inverter to have no DC-side system ground. The micro-inverter AC-side always requires an EGC. I am assuming that the PV modules are in close proximity to the micro-inverters, and the 300' home-run is for the AC outputs of the micro-inverters. Is either DC bus (PV+ or PV-) a grounded conductor, or are both busses ungrounded? If the DC-side combiners and re-combiners have OCPDs and disconnecting means for both PV+ and PV-, then your system is considered to be floating or ungrounded. If the system is ungrounded, a GEC is not required on the DC-side of the micro-inverter, and only an AC-EGC sized per NEC 690.45 is required. If the DC-side combiners and re-combiners have OCPDs and disconnecting means for only one conductor (PV+ or PV-), then
[RE-wrenches] Whisper 500 Service
Hello wrenches, We were hired to service a Whisper 500 turbine installed about 3 years ago by others. It is currently working and producing power. I have a list of improvements I want to make to the original installation including work to the foundation and wiring, but was looking for any advice on other things to look at while the turbine is on the ground. I have the manual which has a list of some pretty obvious things, but was hoping some of you out there with more experience with this unit would be able to offer any advice on specific parts to look at, things to test, or materials and parts that may be useful from your experience. Many thanks! -Nathan -- Nathan J. Stumpff NABCEP Certified PV Installation Professional #091209-175 NABCEP Certified Solar Heating Installer #032412-14 Project Manager | Arctic Sun, LLC nat...@arcticsun-llc.com mailto:nat...@arcticsun-llc.com | (907) 457-1297 www.reina-llc.comhttp://www.reina-llc.com/ | www.arcticsun-llc.comhttp://www.arcticsun-llc.com/ [cid:image001.png@01CEB549.1AFCAC90]http://www.facebook.com/ArcticSunLLC inline: image001.png___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Whisper 500 Service
Nathan, You may do better by posting this to the Wind group, at RE Wind home-wind-t...@lists.re-wrenches.org You may have to get Michael's approval to post, same as with this group. But that's their focus. Allan Allan Sindelar al...@positiveenergysolar.com NABCEP Certified PV Installation Professional NABCEP Certified Technical Sales Professional New Mexico EE98J Journeyman Electrician Founder and Chief Technology Officer Positive Energy, Inc., a Certified B CorporationTM 3209 Richards Lane Santa Fe, New Mexico 87507 505 424-1112 office 780-2738 cell www.positiveenergysolar.com On 9/19/2013 5:24 PM, Nathan Stumpff wrote: Hello wrenches, We were hired to service a Whisper 500 turbine installed about 3 years ago by others. It is currently working and producing power. I have a list of improvements I want to make to the original installation including work to the foundation and wiring, but was looking for any advice on other things to look at while the turbine is on the ground. I have the manual which has a list of some pretty obvious things, but was hoping some of you out there with more experience with this unit would be able to offer any advice on specific parts to look at, things to test, or materials and parts that may be useful from your experience. Many thanks! -Nathan -- Nathan J. Stumpff NABCEP Certified PV Installation Professional #091209-175 NABCEP Certified Solar Heating Installer #032412-14 Project Manager | Arctic Sun, LLC nat...@arcticsun-llc.com | (907) 457-1297 www.reina-llc.com| www.arcticsun-llc.com ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Li-I question
These folks are real I've met with and touched the product. I've been working on a possible use of these but client hasn't said go yet so can't quite yet vouch for the product. http://www.corvus-energy.com/ Kevin -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org]On Behalf Of Allan Sindelar Sent: September 16, 2013 12:58 PM To: RE-wrenches Subject: [RE-wrenches] Li-I question Wrenches, In order to provide accurate information about lithium-ion batteries, I'm looking for referrals to current suppliers with available product, with specifications and retail pricing available. Having read Randy Richmond's article on Li-I in HP153 earlier this year and Dan Fink's posts here, I understand the advantages and limitations. I am just looking for actual supplier websites and contacts, please. Thank you, Allan -- Allan Sindelar mailto:al...@positiveenergysolar.com al...@positiveenergysolar.com NABCEP Certified PV Installation Professional NABCEP Certified Technical Sales Professional New Mexico EE98J Journeyman Electrician Founder and Chief Technology Officer Positive Energy, Inc., a Certified B CorporationTM 3209 Richards Lane Santa Fe, New Mexico 87507 505 424-1112 office 780-2738 cell http://www.positiveenergysolar.com/ www.positiveenergysolar.com ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Li-I question
Looks interesting, I've been waiting for Li+ to start making sense on larger scales. The cycle life does not appear to be better than a HUP lead acid battery, despite the claims of 10 times the cycle life of an AGM battery I'm confused because in their white paper they also claim: 200 cycles at 100% DOD 2000 cycles at 80% DOD 3000 cycles at 80% DOD. What does that mean? Also the warranty has 3 yr free replacement, 10 yr prorated, but doesn't cover shipping or installation, and also demands an engineering evaluation of the installation to allow the warranty. Despite their claims of being the most comprehensive warranty in the business; it is not. My entire power tool collection as well as my computer and phone run on Li+, so I'm a believer, but I've also been vetting BS claims in our industry for over 2 decades. Corvus needs to put more time into some BCI cycle life charts, and provide a warranty that covers shipping and installation time like others. Some case studies, and independent testing would help as well. Anybody have any ball park pricing on this? R.Ray Walters CTO, Solarray, Inc Nabcep Certified PV Installer, Licensed Master Electrician Solar Design Engineer 303 505-8760 On 9/19/2013 9:58 PM, Kevin Pegg wrote: These folks are real I've met with and touched the product. I've been working on a possible use of these but client hasn't said go yet so can't quite yet vouch for the product. http://www.corvus-energy.com/ Kevin -Original Message- *From:* re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org]*On Behalf Of *Allan Sindelar *Sent:* September 16, 2013 12:58 PM *To:* RE-wrenches *Subject:* [RE-wrenches] Li-I question Wrenches, In order to provide accurate information about lithium-ion batteries, I'm looking for referrals to current suppliers with available product, with specifications and retail pricing available. Having read Randy Richmond's article on Li-I in HP153 earlier this year and Dan Fink's posts here, I understand the advantages and limitations. I am just looking for actual supplier websites and contacts, please. Thank you, Allan -- *Allan Sindelar* _Allan@positiveenergysolar.com_ mailto:al...@positiveenergysolar.com NABCEP Certified PV Installation Professional NABCEP Certified Technical Sales Professional New Mexico EE98J Journeyman Electrician Founder and Chief Technology Officer *Positive Energy, Inc.*, a Certified B Corporation^TM 3209 Richards Lane Santa Fe, New Mexico 87507 *505 424-1112 office 780-2738 cell* _www.positiveenergysolar.com_ http://www.positiveenergysolar.com/ ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
