Hi Brian, Thanks for the info. Yes I tested the diode properly. I was concerned that I needed to test the diode under a load to get a valid test.
Taiyoko On Thu, Jul 6, 2017 at 4:14 PM, Brian Mehalic <br...@solarenergy.org> wrote: > Did you use the Diode Test function on the meter? If the diode is good > you should see around 0.4-0.8 V in the forward bias, and OL in reverse. If > it is bad (open) you'll get OL in both directions, and if it is shorted > closed you'll get the 0.4-0.8 V reading in both directions. > > Shorted closed would be the failure mode that would indicate an > always-closed diode providing a permanent bypass path and thus a drop of > 25% of voltage per bad diode (or set of paralleled diodes). (These have 4 > diodes right?). > > > > > Brian Mehalic > NABCEP Certified Solar PV Installation Professional™ R031508-59 > 520.204.6639 <(520)%20204-6639> > > Solar Energy International > http://www.solarenergy.org > > SEI Professional Services > http://www.seisolarpros.com > > > On Thu, Jul 6, 2017 at 4:31 PM, Taiyoko Sadewic < > taiy...@positiveenergysolar.com> wrote: > >> Hi Wrenches, >> We were installing Sanyo HIT modules back in 2006-2007 and in 2014 we had >> a rash of bad Sanyo modules. The modules had distinct voltages below the >> good modules ie 50% or 75%. Sanyo at the time (now Panasonic) indicated >> that it was a bad diodes from a lightning strike not covered by warranty. >> >> I finally got around to checking that out. I identified the purportedly >> bad diode in one module (four per module) that was performing at 75% and >> removed it. The diode appears to be fine using an ohm meter. Is that a >> valid test? >> >> Anyone else have similar findings or experiences with this? Could >> lightning blow apart the tab ribbons inside of the module? >> >> Thanks >> >> -- >> <http://www.PositiveEnergySolar.com> >> Taiyoko Sadewic >> Employee-Owner >> NABCEP™PV Installation Professional >> NABCEP™Technical Sales >> 3209 Richards Lane | Santa Fe, NM 87507 >> cell 505.570.0137 <505.699.9032> >> taiy...@positiveenergysolar.com <taiy...@positiveenergysolar.com> >> www.PositiveEnergySolar.com >> <http://www.positiveenergysolar.com/> >> <http://www.facebook.com/positiveenergysolar> >> <https://twitter.com/PositiveESolar> >> <https://plus.google.com/+Positiveenergysolar> >> <https://www.youtube.com/user/PositiveEnergySolar> >> <https://www.positiveenergysolar.com/blog/blog/> >> <https://www.positiveenergysolar.com/contact/refer-a-friend/> >> <https://www.bcorporation.net/community/sunpower-positive-energy-solar> >> <http://www.solarreviews.com/installers/positive-energy-solar-reviews/> >> >> _______________________________________________ >> 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 >> -wrenc...@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 > > > -- <http://www.PositiveEnergySolar.com> Taiyoko Sadewic Chief Financial Officer | Employee-Owner NABCEP™PV Installation Professional NABCEP™Technical Sales 3209 Richards Lane | Santa Fe, NM 87507 cell 505.570.0137 <505.699.9032> taiy...@positiveenergysolar.com <taiy...@positiveenergysolar.com> www.PositiveEnergySolar.com <http://www.positiveenergysolar.com/> <http://www.facebook.com/positiveenergysolar> <https://twitter.com/PositiveESolar> <https://plus.google.com/+Positiveenergysolar> <https://www.youtube.com/user/PositiveEnergySolar> <https://www.positiveenergysolar.com/blog/blog/> <https://www.positiveenergysolar.com/contact/refer-a-friend/> <https://www.bcorporation.net/community/sunpower-positive-energy-solar> <http://www.solarreviews.com/installers/positive-energy-solar-reviews/>
_______________________________________________ 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