<div dir="auto"><div>Comment below -<br><br><div data-smartmail="gmail_signature">------------------------------------------------------------------<br><br>Martin Herzfeld, Interstate Renewable Energy Council (IREC) Certified Master Trainer™ Emeritus<br>California Solar & Electrical Contractor License #00833782 C-46, C-10, C-7, C-61 - D-56, D-31<br>Solar, Electrical, Trenching, Pole Installation & Maintenance, Instrumentation<br><br>Underwriters Laboratories (UL) Certified PV Systems Installer #17, OSHA 30 Certificate<br>OSHA-Authorized Construction Safety Trainer #32-0106614<br>CompTIA® Certified Technical Classroom Trainer (CTT+™ Certified) #T3NSZCNBBKB4QTQG<br>Solar & Electrical Construction Consultant - 2nd Party Evaluations<br><br>International Code Council® (ICC) Certified Residential Electrical Inspector - E1 #8343181<br>International Association of Electrical Inspectors (IAEI) Member - #7035507<br>Electric Vehicle Infrastructure Training Program (EVITP™) Certification #4039206<br>Contract Solar (PV) Technical Inspector - 3rd Party Inspections<br><br>Certificate - Stanford | Center for Professional Development - Energy Innovation and Emerging Technologies (EIET)<br><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Jun 19, 2023, 11:33 AM August Goers via RE-wrenches <<a href="mailto:re-wrenches@lists.re-wrenches.org" rel="noreferrer noreferrer noreferrer noreferrer noreferrer" target="_blank">re-wrenches@lists.re-wrenches.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">Hi William - Is this a <a href="https://files.sma.de/downloads/SB3-5TL-21-IS-xx-14.pdf?_ga=2.101814081.1325009506.1687199204-2010138759.1678983058" rel="noreferrer noreferrer noreferrer noreferrer noreferrer noreferrer" target="_blank">TL-21 inverter</a> line from maybe 8 or 10 years ago? If I recall correctly, that was around the time period that SMA was first shipping with AFCI detection - we had a few SMA inverters from that vintage producing false AFCI errors. I think that long home runs can be part of the issue and the inverter circuitry was a little too sensitive. You might try calling SMA to see if there is a firmware update or a way to disable AFCI if you feel comfortable with disabling that safety feature. </div></blockquote></div></div><div dir="auto"><br></div><div dir="auto">Simply, would this be 690.11 and not be a situation of comfort, but "not in or on buildings," "metal(lic) raceways" or other requirements to comply with the exception? </div><div dir="auto"><br></div><div dir="auto"><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">Separately, we've had a few phantom type AFCI errors on older modules and after tons of troubleshooting we think that it might have been internal to the modules themselves. <div><br></div><div>Good luck!</div><div><br></div><div>Best, August<br><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Jun 19, 2023 at 11:11 AM William Miller via RE-wrenches <<a href="mailto:re-wrenches@lists.re-wrenches.org" rel="noreferrer noreferrer noreferrer noreferrer noreferrer noreferrer" target="_blank">re-wrenches@lists.re-wrenches.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div><div lang="EN-US"><div><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif"">Friends:</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif"">We installed a bunch of Shell SQ-150-PC modules on a ground mount almost 20 years ago. The original SB2500 inverters died so we upgraded to SB4000US-21 inverters. We had some ground fault or AFCI issues a number of years ago so we replaced all homeruns with PV wire which resolved the problem. </span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif"">These panels have J-boxes which we interconnected with 1/2” NMLT. The home runs are with PV wire with absolutely no splices and the inter-panel jumpers are THWN.</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif"">Recently we started getting AFCI disturbances on one inverter. We isolated the fault to one string. We opened every pull box and panel J-box and all of the wiring looks dry, clean and tightly connected. We inspected every panel front and back and see no hotspots or visible corrosion.</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif"">I have a megger I have never used. The homerun is kind of long so maybe it has insulation problems. I could isolate the homerun and megger those leads. I am researching if I can megger PV modules. It looks like this is commonly done. That looks like my next step.</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif"">Does anyone have any ideas on what I should do next? I suppose I could start swapping each of the 10 modules in the problem string with panels in the non-problem strings, but that seems like a lot of work.</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif"">Thanks in advance.</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif"">William Miller</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Verdana,"sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Arial,"sans-serif"">Miller Solar</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Arial,"sans-serif"">17395 Oak Road, Atascadero, CA 93422</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Arial,"sans-serif"">805-438-5600</span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Arial,"sans-serif""><a href="http://www.millersolar.com/" rel="noreferrer noreferrer noreferrer noreferrer noreferrer noreferrer" target="_blank">www.millersolar.com</a></span></p><p class="MsoNormal"><span style="font-size:12pt;font-family:Arial,"sans-serif"">CA Lic. 773985</span></p><p class="MsoNormal"> </p><p class="MsoNormal"> </p></div></div>
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