Re: [RE-wrenches] Finding ground faults
Hey Bob ! Hi from the west side of the hill. This seems like an easy one... Well, maybe... One a dry day, take a garden hose and spray different parts of the system and see if you can duplicate the problem and locate where the water makes it trip. But you may have to wait a while for each spot sprayed to let it fault out before spraying another spot. That's how I'd start out. This also seems kind of weird in a way because of the current necessary for that breaker to trip. What ? 1/2 amp or 1.0 amp or so That's not a real small amount for rain. I bet something is rusty or corroded or something like that. Please let us know what you find !! boB On 5/22/2012 7:36 PM, Bob Clark wrote: Wrenches: Sorry to bring up this situation again, but I could not find a previous discussion thread that talked about step-by-step procedures for tracking down ground faults (I believe it was John Berdner who provided the bulk of the writing in that regard and it related to high voltage strings---not that 75-85 volts per string is all that low). We have an Outback FLEXpower Two system with 8, 3-module strings (Silicon Energy 190W, 25.3Vmp, 7.5 Imp) combined in a Midnite Solar MNPV12 combiner with breakers. The cables from the array are routed to two different Wiley 4-string pass-through boxes (located under the two center strings) and then off of the roof and into the PV combiner. Up until this week the system has seen several weeks of awesome power production. Yesterday, the rains came and the GFDI breaker tripped. Every time it rains, the little green breaker on the GFDI trips off. That tells me that the ground fault is occurring in a place where at least one of the conductors on one of the strings (possibly more) is getting wet and conducting current to ground. It would seem to me that the most likely place for moisture to cause a ground fault to occur in this system would be in the pass-through boxes. This would mean removing the central modules to access the pass-through boxes. Any of you who have mounted the Silicon Energy modules know that the cables are contained in trays along the side of the modules until they are routed through conduit to the pass-through boxes. So, if there is current going to ground from any of these cables, it could even be occurring in any of the 9 trays along side of the modules. I do not like the idea of tracking down a ground fault in one of these trays as they are all interconnected. How best (and safely) to track down where the ground fault is occurring? Any advice as to the best and safest way to track down the ground fault(s) would be greatly appreciated. *Bob Clark* */SolarWind Energy Systems, LLC/* ___ 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] Finding ground faults
A problem I have seen during my work with SiE is getting the "tray" covers on without pinching a wire, if one of the black plastic bolt guards was left off or lost, it could pinch, but they seem water-tight. I haven't run into any fault problems with SiE, but I see the possibilities. Keep me informed if you can. I have 3 11kW systems using SiE modules coming up this summer so I'm interested in where this is occurring. Jesse Sent from my iPad!!! On May 22, 2012, at 9:36 PM, "Bob Clark" wrote: > Wrenches: > > Sorry to bring up this situation again, but I could not find a previous > discussion thread that talked about step-by-step procedures for tracking down > ground faults (I believe it was John Berdner who provided the bulk of the > writing in that regard and it related to high voltage strings—not that 75-85 > volts per string is all that low). > > We have an Outback FLEXpower Two system with 8, 3-module strings (Silicon > Energy 190W, 25.3Vmp, 7.5 Imp) combined in a Midnite Solar MNPV12 combiner > with breakers. The cables from the array are routed to two different Wiley > 4-string pass-through boxes (located under the two center strings) and then > off of the roof and into the PV combiner. > > Up until this week the system has seen several weeks of awesome power > production. Yesterday, the rains came and the GFDI breaker tripped. Every > time it rains, the little green breaker on the GFDI trips off. That tells me > that the ground fault is occurring in a place where at least one of the > conductors on one of the strings (possibly more) is getting wet and > conducting current to ground. > > It would seem to me that the most likely place for moisture to cause a ground > fault to occur in this system would be in the pass-through boxes. This would > mean removing the central modules to access the pass-through boxes. > > Any of you who have mounted the Silicon Energy modules know that the cables > are contained in trays along the side of the modules until they are routed > through conduit to the pass-through boxes. So, if there is current going to > ground from any of these cables, it could even be occurring in any of the 9 > trays along side of the modules. I do not like the idea of tracking down a > ground fault in one of these trays as they are all interconnected. > > How best (and safely) to track down where the ground fault is occurring? Any > advice as to the best and safest way to track down the ground fault(s) would > be greatly appreciated. > > Bob Clark > SolarWind Energy Systems, LLC > ___ > 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-wrenches] Kohler 10RY rewire to 120
Hello wrenches, Does anyone have any good instructions or advice on how to rewire an older Kohler 10RY generator to 120VAC from 120/240? I have heard it is simple, but haven't gotten anything specific yet. Thanks! -- Mac Lewis * "Yo solo sé que no sé nada." -Sócrates * ___ 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] Finding ground faults
Wrenches: Sorry to bring up this situation again, but I could not find a previous discussion thread that talked about step-by-step procedures for tracking down ground faults (I believe it was John Berdner who provided the bulk of the writing in that regard and it related to high voltage strings-not that 75-85 volts per string is all that low). We have an Outback FLEXpower Two system with 8, 3-module strings (Silicon Energy 190W, 25.3Vmp, 7.5 Imp) combined in a Midnite Solar MNPV12 combiner with breakers. The cables from the array are routed to two different Wiley 4-string pass-through boxes (located under the two center strings) and then off of the roof and into the PV combiner. Up until this week the system has seen several weeks of awesome power production. Yesterday, the rains came and the GFDI breaker tripped. Every time it rains, the little green breaker on the GFDI trips off. That tells me that the ground fault is occurring in a place where at least one of the conductors on one of the strings (possibly more) is getting wet and conducting current to ground. It would seem to me that the most likely place for moisture to cause a ground fault to occur in this system would be in the pass-through boxes. This would mean removing the central modules to access the pass-through boxes. Any of you who have mounted the Silicon Energy modules know that the cables are contained in trays along the side of the modules until they are routed through conduit to the pass-through boxes. So, if there is current going to ground from any of these cables, it could even be occurring in any of the 9 trays along side of the modules. I do not like the idea of tracking down a ground fault in one of these trays as they are all interconnected. How best (and safely) to track down where the ground fault is occurring? Any advice as to the best and safest way to track down the ground fault(s) would be greatly appreciated. Bob Clark SolarWind Energy Systems, LLC ___ 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
