Esteemed wrenches: Well if my house is on fire and the entry of fire responders is delayed for lack of a disconnect, I choose having the disconnect. I can worry about the charge controllers later.
Others may prioritize their charge controller over their homes… Put a cable-tie lock in the closed position to discourage kids from messing with it. Test it only after dark. William On Sat, Jan 28, 2023 at 2:32 PM William Bryce <wlbr...@pineridgeproducts.com> wrote: > All > > One thing that no one is talking about is what happens to the MPPT charge > controllers when the Battery Disconnect trips when the charge controllers > are under full load. > Many will blow up. Try turning off the battery breaker on a SolaArk when > the charge controllers are maxed, and see if you get lucky. > > On Sat, Jan 28, 2023 at 3:27 PM William Miller via RE-wrenches < > re-wrenches@lists.re-wrenches.org> wrote: > >> Jeremy: >> >> >> >> Thanks for posting the code references for those that had never looked >> them up. >> >> >> >> Chris: >> >> >> >> What do you mean by “a disconnect for AC wiring, not specific to which >> or both panel types”? >> >> >> >> All: >> >> >> >> Code references are handy when receiving edicts from building officials, >> but not required, IMHO, for two reasons: The contractor should already be >> versed in the codes and, building departments can mandate their own >> requirements above and beyond the code. >> >> >> >> It may seem redundant to require an AC disconnect for premise wiring as >> well as a DC battery disconnect. In most cases if you disconnect the >> inverter from the batteries the AC power goes off. However if the >> generator is running at the time, some battery inverters can operate when >> disconnected from batteries. So to completely de-energize all components >> of an off-grid home you need to disconnect the generator and the battery >> leads. >> >> >> >> In this case the home is required to have fire sprinklers. There is >> pressure pump to provide flow to these fire sprinklers-- said pump being >> powered by the inverter/battery system. I am going to apply for a waiver >> to remove the DC disconnect requirement on the grounds that the pressure >> pump is essential fire suppression equipment. Instead I will propose to >> supply an AC disconnect (meeting all requirements for accessibility and >> marking) that will disconnect all premise wiring except the pressure pump. >> >> >> >> By the way, I will of course be trying to apply the logic that the >> voltage specification is for nominal battery voltage and this project >> having a nominal 48 volt bank does not require the battery disconnect. >> >> >> >> I will let the group know what response I receive. Regardless of how >> this works in this jurisdiction, I think these are both valid arguments >> worth trying in any jurisdiction requiring the battery disconnect. Some >> officials are amenable to dialog and negotiation and some are less so. >> >> >> >> >> >> William Miller >> >> >> >> Miller Solar >> >> 17395 Oak Road, Atascadero, CA 93422 >> >> 805-438-5600 >> >> www.millersolar.com >> >> CA Lic. 773985 >> >> >> >> >> >> *From:* RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] *On >> Behalf Of *Jeremy Rodriguez via RE-wrenches >> *Sent:* Saturday, January 28, 2023 10:12 AM >> *To:* cwar...@entech-engineering.com; RE-wrenches >> *Cc:* Jeremy Rodriguez >> *Subject:* Re: [RE-wrenches] Remote battery disconnects >> >> >> >> >> >> *2020 Code Language:* >> >> *480.7 DC Disconnect Methods.* >> >> *(A) Disconnecting Means.* *A disconnecting means shall be provided for >> all ungrounded conductors derived from a stationary battery system with a >> voltage over 60 volts dc. A disconnecting means shall be readily accessible >> and located within sight of the battery system.* >> >> *N* *(B) Emergency Disconnect.* *For one-family and two-family >> dwellings, a disconnecting means or its remote control for a stationary >> battery system shall be located at a readily accessible location outside >> the building for emergency use. The disconnect shall be labeled “EMERGENCY >> DISCONNECT”.* >> >> *N **(C) Disconnection of Series Battery Circuits.* *Battery circuits >> exceeding 240 volts dc nominal between conductors or to ground and subject >> to field servicing shall have provisions to disconnect the series-connected >> strings into segments not exceeding 240 volts dc nominal for maintenance by >> qualified persons. Non-load-break bolted or plug-in disconnects shall be >> permitted.* >> >> >> >> Jeremy Rodriguez >> >> Solar Installation / Design >> >> All Solar, Inc. >> >> 1453 M St. >> >> Penrose Colorado 81240 >> >> >> >> Sent by Jeremy's iPhone. Sorry for typos and shorthand. >> >> >> >> On Jan 28, 2023, at 7:28 AM, Christopher Warfel via RE-wrenches < >> re-wrenches@lists.re-wrenches.org> wrote: >> >> >> >> Seems confusing that the AHJ is requiring a disconnect for AC wiring, not >> specific to which or both panel types, and then a dc disconnect with no >> code reference. Was trying to convey a reasonable, safe approach. A lot >> of bad information from fire department solar consultants making a lot of >> money fear mongering, which has led to this type of situation. Chris >> >> On 1/27/2023 3:35 PM, William Miller via RE-wrenches wrote: >> >> Glenn: >> >> >> >> As I wrote, a DC disconnect is required. Here is an excerpt from the Q&A >> with the building official: >> >> >> >> 4. Will you be requiring an external disconnect to disconnect the AC >> output of the inverter system from premise wiring? >> >> Yes, as required per 230.85 >> >> 5. Will you be requiring an external disconnect to disconnect >> batteries from the inverters? >> >> Yes >> >> >> >> If the DC disconnect was not required I would not be wasting everyone’s >> time with my post. I try to be careful about that, researching on my own >> before posting and trying to make my questions very clear. I also try not >> to embarrass myself with dumb questions, but that does happen occasionally… >> >> >> >> William >> >> >> >> Miller Solar >> >> 17395 Oak Road, Atascadero, CA 93422 >> >> 805-438-5600 >> >> www.millersolar.com >> >> CA Lic. 773985 >> >> >> >> >> >> *From:* RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] *On >> Behalf Of *Glenn Burt via RE-wrenches >> *Sent:* Friday, January 27, 2023 11:46 AM >> *To:* William Miller via RE-wrenches >> *Cc:* Glenn Burt >> *Subject:* Re: [RE-wrenches] Remote battery disconnects >> >> >> >> Does the AHJ really want the batteries disconnected from conductors, or >> does he really just want the inverters to stop operating and producing AC >> within the house? >> >> Obviously there is a big difference here and it may be changing as the >> code evolves. >> >> >> >> -Glenn >> >> Sent from my 'smart'phone, so please excuse typos and spelling errors. >> >> >> >> ------ Original message------ >> >> *From: *William Miller via RE-wrenches >> >> *Date: *Fri, Jan 27, 2023 2:26 PM >> >> *To: *RE-wrenches; >> >> *Cc: *William Miller; >> >> *Subject:*[RE-wrenches] Remote battery disconnects >> >> >> >> Friends: >> >> >> >> We have a large-ish residential off-grid system install coming up. The >> AHJ has said they will require a remote battery disconnect. I suspect >> there will be fire sprinkler controls and a pressure pump that would become >> inoperable if this system were engaged. In this case we will apply for a >> waiver. >> >> >> >> The last time this was discussed here as far as I can find was October of >> 2020. At that time no one suggested any specific battery disconnect >> equipment. >> >> >> >> To further clarify my needs: There will be 4 or 5 Radian 8048 inverters >> (5 or 6 4/0 battery circuits, ~350A each) and two 175 amp PV recombiner >> outputs. That is 6 poles of high amperage DC disconnects. >> >> >> >> The battery array will be either a UnigyII VRLA or a lithium of a brand >> yet to be determined. In the case of lithium we will look for a system >> that can remotely enable a BMS shutdown. In the case of a VRLA lead-acid, >> we will not have that luxury. >> >> >> >> I have done some considerable research and have not found viable, high >> amperage, remotely activated shutdown equipment. >> >> >> >> I am wondering what hardware others may be using to achieve remote >> battery disconnecting in these types of cases.. >> >> >> >> William >> >> >> >> Miller Solar >> >> 17395 Oak Road, Atascadero, CA 93422 >> >> 805-438-5600 >> >> www.millersolar.com >> >> CA Lic. 773985 >> >> >> >> >> >> >> >> _______________________________________________ >> List sponsored by Redwood Alliance >> >> Pay optional member dues here: http://re-wrenches.org >> >> 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 >> >> There are two list archives for searching. When one doesn't work, try the >> other: >> https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ >> http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org >> >> List rules & etiquette: >> http://www.re-wrenches.org/etiquette.htm >> >> Check out or update participant bios: >> http://www.members.re-wrenches.org >> >> -- William Miller Miller Solar.com 895-438-5600 www.millersolar.com
_______________________________________________ List sponsored by Redwood Alliance Pay optional member dues here: http://re-wrenches.org 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 There are two list archives for searching. When one doesn't work, try the other: https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: http://www.re-wrenches.org/etiquette.htm Check out or update participant bios: http://www.members.re-wrenches.org
