[RE-wrenches] Conext xw+ 6848 inverter 1.5 minute voltage increase
I am placing this inquiry out to see if anyone else has experienced a similar experience. An electrician friend near Taos, NM, installed a Conext XW+ 6648 inverter on a large 2nd seasonal (remote stand alone PV supplied) vacation home, (used less than 10 weeks per year), it has a large 48 VDC AGM battery (40+kW-Hr) and almost a 7.0 kW PV Array and a back-up LP gen-set. It has a Xantrex accessories : Com-Box, charge controllers, bat monitor, etc. The anomaly this system exhibits is that - when the owners are infrequently present - during each evening, for about 90 seconds - the 120vac lights get noticebly brighter. After this brief event, the lights exhibit normal behavior. No lights or appliances are functionally damaged. It is more of a nuisance than an actual problem. This usually happens between 9:30 and midnight. The timing seems to be arbitrary - as no known load either turns on or turns off in conjunction with this event. Xantrex has been consulted and the inverters firm ware has been upgraded and they even sent a replacement inverter control board, which after its replacement nothing changed. As this is quite late at night and has been happening both in winter and in summer months, it is not presently believed to be associated with the PV modules or charge controller. Conventional wisdom implies, that if there is some significant load was cycling in the background - the lights would dim - not brighten. I have never heard of anything like this and was wondering- if any had. There are no known large capacitive loads on the system. Any one seen anything similar, I was asked - as I have been doing systems in New Mexico since 1995 and I guessed it was a well/ water pressure bladder tank system related issue . . . but the installer has witnessed this, at night when the water pump and well remained off. ? Item 2) some weeks ago, it was noted on this RE-Wrenches thread that some ballast blocks, 4” x 8” x 16” were starting to suffer decomposition and a solution was sought, I guessed that this might be due to water seepage and repeated freezing and thawing. Has anyone used an inexpensive masonry sealer painted on the blocks, to stop water wicking to the concrete ballast blocks? There is very thick cinder block paint (UGL) for cinder block foundations that would be quite expensive and polyurethane is very pricey too - I would like to recommend that works successfully and is economical for existing installations rather than replacing hundreds of blocks? Thanks, Daniel O. Duffield NABCEP Certified PV Installation Professional (2005) NM licensed Commercial Electrical Contractor EE98/ER01 IEEE member 23 years ___ 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
[RE-wrenches] Battery tester, Vol 11, issue 68
The tester for battery banks I have used for many years is somewhat pricey, but well worth it, since reserve battery banks are the single item in most stand-alone that are most difficult to quantify and now storage is finding is inevitable way into grid connected PV systems. The unit I would recommend is called, Mid-Tronics CTU 6000 Celltron Ultra stationary battery tester. This unit was first introduced to me, when I travelled around New Mexico and serviced Mitsubishi (zero transfer time) 3 phase Uninterruptible Power Supplies, powered by either 30 - 12 volt batteries wired in series or 40. These are lethal dc voltages, but these unit also work on 12, 24 or 48 system. These units perform something like an impedance test, actually a conductance test - mhos. They record data sets on an SD card and you can immediately print out the results on site. I have used these to test hundreds of GNB-Absolyte VRLA AGM batteries over the years. The have other benefits- which I won’t get into detail here, but they are worth investigating, if you want details. I took my time and found a good unit, at a decent price on eBay from a re-seller with a good feedback rating. They come with some of the major battery type reference cell values within the unit for comparison of you can add a value yourself after consulting the specific battery type your testing from the mfg. The only limitation is - this is a cell tester and when testing you need physical access to the individual cells to place the testing probes upon. Most large amp-hour banks are made up of as few parallel strings as possible- which leads battery designers to produce batteries with progressively large amp- hour 2volt cells, whose terminals are directly accessible via bus work. If you have a 6 volt/12 volt building block, like a L-16 or a 12-volt group 30 footprint type battery- you can’t measure the individual cells within. If you have a very large number of banks to test, you place your probes on the 2 volt cell terminals and wait for an audible beep, prior to moving on to the next successive cell in your string. In this manner you and be accurate and fast These work very well at finding issues and indicating how relatively close or far away the measured conductance value is from a known good value. Thanks, Daniel O. Duffield, NM EE98, NABCEP Certified PV Installation Professional. IEEE member. ___ 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
Re: [RE-wrenches] RE-wrenches Digest, Vol 10, Issue 152
Sent from my iPhone > On Jun 22, 2017, at 6:07 AM, re-wrenches-requ...@lists.re-wrenches.org wrote: > > Send RE-wrenches mailing list submissions to >re-wrenches@lists.re-wrenches.org > > To subscribe or unsubscribe via the World Wide Web, visit >http://lists.re-wrenches.org/listinfo.cgi/re-wrenches-re-wrenches.org > or, via email, send a message with subject or body 'help' to >re-wrenches-requ...@lists.re-wrenches.org > > You can reach the person managing the list at >re-wrenches-ow...@lists.re-wrenches.org > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of RE-wrenches digest..." > > > When responding to posts within the Digest, be sure to restore the Subject: > line to the original, and please edit out any extraneous lines from the > quoted message. > > > Today's Topics: > > 1. Re: Rodent/Pigeon/Critter Guards (Benn Kilburn) > 2. Solar over a pool - what must I pay attention to? (Howard Arey) > 3. Re: Solar over a pool - what must I pay Our go to 3M all weather pressure sensitive adhesive tape (double sided) a product called VHB and it's performance has been excellent. On PV above pools, I don't have a code book in front of me but my experience is conductors about the pools, have to be some astronomical number of feet above the surface of the water, I think it was 25', pretty much eliminates most structures, being builtafter the fact, from being used - it's very prohibitive and it's because the splashing I think. With Roofs not being optimally laid out for PV, shade, chimneys, trees, available PV space is at a premium. The best we did was the set up patio or gazebos structures adjacent to pools and created usable shade space and place PV there -when there was available backyard space Daniel O. Duffield NABCEP PV INSTALL Professional NM EE98 & ER01 ___ 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
Re: [RE-wrenches] Classic 150 100 amp output breaker tripping
Some years ago, we had a similiar problem with a 50 amp breaker nuisance tripping, we over analyzed the problem and still could not prevent this erratic issue, sometimes it would work fine for weeks - sometimes days apart, sometimes on sunny days, sometimes on cloudy days. In the end the answer was simple and so easy it was overlooked more than once. It was just a matter of the proper torque, with the copper compression fitting on a Sq D QO breaker, just a hair breathe too loose, enough heat would build over many hours to change the trip curve. We measured, swapped breakers, everything you could think off until we employed a torque wrench with a screwdriver bit. Problem vanished, never to come back. Not saying this is answer, but sometimes tightening a compression fitting to the correct "feel", by a journeman electrician with 20 years experience, is not good enough. If your crew or organization has torque screwdrivers, we had no excuse not to use them, and back then we found out the hardway. Daniel O. Duffield NABCEP Certified PV Installer since 2005 EE 98 & ER01, Albuquerque, New Mexico, IEEE member 1995 DPW Solar (Integration-Division) > ___ 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
[RE-wrenches] ARRA act
Topic - a Question - Anyone know if there is a trade group or solar representation group that has a website that lists: Solar PV and Solar Thermal products that comply with the ARRA act, (American Resource and Recovery Act, i.e., stimulus funds)- from my review, only those projects where project price is more that a certain dollar amount: ~ 7.4 million and above, will allow the use of products manufactured outside the US, provided that are made in a country that is a trading partner under the NAFTA treaty or the WTO treaty. Systems smaller than this; all products must be made, manufactured, assembled with the US, where significant assembly or added value work is accomplished. To buy American products for projects that require ARRA compliance - it might make a lot of sense for SEPA or ASES or even one of the trade magazines such as Solar Pro Magazine - so that the incentive mechanism itself work(s); that is - a prospective client could be shown, in advance, from a 3rd party referral site - who takes this listing or posting of various US made solar equipment on - like dsireus.org did with state and local incentives. This would be better than an he said, she said approach or having to track down the legal department of brand X, Y, and Z solar equipment. Does such a resource presently exist, inquiring minds want to know. There are two PV module mounting systems manufacturers based here in Albuquerque, NM. and we are one of them. We have been approached by no group, as far as I ( others here) know for listing or providing info proving such. Thanks Daniel O. Duffield NABCEP Certified Installer(tm) Licensed NM Electrical Contractor IEEE member duffie...@directpower.com Direct Power Water Corporation a division of PLP (Preformed Line Products) ___ 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
