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Kalahari Meerkat

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Everything posted by Kalahari Meerkat

  1. Yes I can't think of why not, they're both AC and should be protected in their respective DB with a CB of appropriate value Earth should be earth in your installation, whether the dedicated plug come off a UPS/Inverter or just pre Earth leakage trip switch, the earth for all electrical connections should be the same... so, I'd say you can probably use the same earth for both plugs... maybe some else can come up with a scenario where it may be better to keep the earths for the 2 plugs separated. but offhand, I can't think of any reason...
  2. Maybe, but all I've seen so far (haven't looked on Alibaba as yet) are 18650 Cells and then they aren't exactly high energy, compared to NMC or LCA 18650's they are less than half the capacity, I didn't see a price for these, but they'd have to come in at less than 30 ZAR per cell (much less, I reckon) before they may become interesting... I'm not negative, but I am not seeing anything of real interest as yet either... so, for now, I am aware of it, but heck probably at least another 3 years and maybe even some chemistry tweaks before this lot may become more interesting and have some useful application...
  3. Ok, well, no electronics I have would be happy with a more than 2:1 range of Voltage source... 3.95V to 1.5V... and I think, even though it appears you can purchase some (small/low capacity) cells, they are not ready for the market, or the market is not ready for them, take your pick, I'll take another look in another 18 months and look at what they are about by then... and @Scorp007 after you have ordered some and played around with them, let me/us know what you think, are they ready to replace LiFePO4's and at what cost? I suspect not nyet or any time soon, specifically I can not name any inverters that would be happy with the voltage range this chemistry seems to operate under...
  4. @sunset1 here's another possible (10 years to market) battery option... aqueous metal ion batteries but again a long way to go and not much info, but 85% capacity remaining after 500 cycles, doesn't quite excite me...
  5. I doubt there's a rule where AC and DC is supposed to be as long as it is separated and since its marked, unless you have a blind electrician, it should be fine, I reckon. @Gerrie I see you used plastic conduit on the roof, less than ideal, but keep an eye on it, not sure how it weathers in your neck of the woods, here it would crumble within 24months, I suspect, but also for lightning induced currents, metal conduit would have been betterer...
  6. Last I checked they were still sitting at less than 1000 cycle life and I didn't see any advertised for sale, either way, I suspect it has quite a road to travel still... and just like the Al-Ion boys, they'd like the *LARGE* market, the EV market to be their customer, comparing the home solar+battery market size with the EV market is like comparing a flea with a heard of elephants...
  7. you mean 1200VA or 1.2kVA I would NOT go with Lead Acid anything, they will die before the Sodium Ion batteries come to market and the next problem will be how good will the initial Sodium Ion batteries be, you may as well go for LiFePO4's for now and you should still be able to sell them in 5 years time, since they should still be in good shape and operational by then, else you can look at Aluminum or Aluminium Ion batteries, they should also be with us in the next 3 to 5 years time as well, I'd hope...
  8. V/R=I aka V/I=R aka R*I=V V would be 25V or thereabouts, R you said app. 20 Ohm, thus 25/20=1.25Amperes, which for 10 seconds or so, should have been plenty, but a 1 or 2 Ohm resistor, for a second or two, would also have been fine, since 25V/1Ohm=25Ampere, which your battery should have been happy to supply without anything else tripping, I would think... Anyway, glad it is all working now...
  9. Probably not, I'd think, but its likely to be SoC misrepresentation probably by the battery to the Inverter, can you see how much discharge there was, by the time the HWC switches on? Maybe you find you did actually get nearly 80% out already and then the HWC switches on and then the real SoC starts to actually be displayed... Sunsynk is not the worst product around, by far, but not retaining competent support staff in this country has pretty much caused them to shoot themselves in the foot, lots of unhappy customers, since the failed inverters are not repaired/sorted out within a realistic time frame, when things go wrong... but also, why are there so many failures and specifically during the Lightning season in the north-eastern part of the country, is this maybe more an installation related problem, rather than a product failure? I don't know, but it should be trivial to look at number of SunkenSynk inverter in Transvaal (encompasing GP, MP, NW etc.) and how many in the Western Cape, for instance and then look at the failure %ages based on location... I'd be interested to see what the outcome of this would be... and could tell a story that might prescribe a way to install with all surge protection in place etc. that may well reduce the amount of failures...
  10. Does not matter, I'd think, since presumable the existing one could supply 1C to the inverter, now they would be C2 or 0.5C and the new battery being twice the size of each of the two existing ones would then sit at C4 or 0.25C thus really idling along... and I doubt its specs would only be 0.25C...
  11. As long as the Volta is also 16S, then that should be no problem, the comms may not work, in which case just let either the Shotos do the talking, or the Volta, but different capacities is no problem, the charge and discharge power will be split 25% each for each of the Shotos and 50% for the Volta, give or take a percent or two either way. So in effect the power will be spread over the 3 batteries roughly evenly based on the power capability.
  12. You can mix, however for Lithium type batteries, you would have to stick to the same chemistry, thus if you have LiFePO4 based batteries, then that would have to be the same for the new batter(y/ies), also the amount of cells need to be the same, thus if you have a 15S (15 series cell) LiFePO4 battery, 48Volt nominal, then the new ones also need to be the same and if its 16S LiFePO4 batteries, 51.2Volt nominal, again, you need to stick to what you have chemistry and series cell count wise. If you are using BMS comms to your inverter, the different brands may not happily co-exist from that perspective, but that should not be a problem, charging and discharging they will track each other fairly closely, I for instance have a 8k2Wh 16S LiFePO4 battery which talks to my inverter, I have added a 16S 300-odd Ah LiFePO4 battery without comms from its JK BMS, but it all works well, the 300Ah is usually within less than 5% of the SoC of the smaller battery.
  13. Not a electric fence expert, however... any plant growing close to the electrified portion or even touching the electrified portion permanently are likely to cause problems, this may not be the problem in your case, if you have walked/checked the fence...
  14. The problem here is who/what is determining the SoC, what inverter are you using and what is reporting the SoC? Some BMS' seem to thumbsuck a figure based on cell voltage, same with some inverters, when really coulomb counting should be done, the BMS should know the cell capacity and thus based on energy in/energy out, determine a SoC, but if the battery never gets full properly and has time to do balancing, then the SoC can be a useless figure, BSL's can do this, they, via a SunkenSynk inverter claim 100%SoC, which is bull, since if you have energy available they will continue consuming many Amps/Watts for maybe even an hour or more after claiming to be at 100% SoC. So, you batteries probably need to be charged properly by your inverter, until they will not consume any more energy, then they should be at 100% SoC and then you can see what they would do, but if the BMS determines charge level based on Voltage, then the provided figure will always something that is of dubious value.
  15. Thanks for not answering in which suburb you are, but the above statement of yours pretty much implies you are in some oldish suburb that still has overhead cabling, in Bellville, for the most part, everything is underground and single phase, good luck getting them to put in 3 phase and speaking regularly to a friend in Australia, I am quite aware about the line voltage issues with solar end user feed ins, if the whole area/infrastructure was designed with this in mind, maybe the line voltage does not rise as much, but in established neighbourhoods that have been about for 40 years or more, this may not be the case. Heck if you raise the line voltage by 2 volts and if you had 10 neighbours doing the same feed in thing your line voltage would probably be more like 20-odd Volts up and if it started at 240V, you are starting to get to a level where things can and do go wrong. Don't think your are feeding into a countrywide grid, there are transformers all over the show and in suburbs there are substations with transformers, which feed a finite number of houses and are thus also rated for a finite amount of power transfer....
  16. @NoJ, since you are not answering the questions posted by various posters, please answer the following... 1. In which suburb are you located? 2. You are on 3 phase, how much current per phase? 3. Previously asked by someone else, what inverter make and models are you using specifically? Now I will add, most Cape Tonians do not have 3 phase and thus would not be able to shove the amount of energy into the local grid connection that you seem to be able to, if everyone in a specific suburb was trying to, the local line voltage would be 260+V where some equipment, not too happy anymore would start letting out the smoke... and most inverters would disconnect from the grid connection due to overvoltage conditions...
  17. I would imagine they would, but... the Revov were initially all 2nd life batteries as far as I know and if this is still the case, then your battery's cells have already a few thousand cycles behind them and should be betterer balanced by now, but if they are new cells, not 2nd life, then they may take a while... ideally you don't want a cell in the pack going quite this high/3.6V but that to a degree is also a function of the BMS... most of these crummy BMS use a resistor per cell to bleed off excess energy and this could take a while... every charging cycle...
  18. Hmmm... no BMS, I see and not compressing your cells... no 10 000cycles for that one, I suspect... didn't want photos of your inverters, just all the panels to see how clear they are and how *large* a property you have, since your setup would not likely fit onto most Cape Town city lots, I suspect...
  19. That goes without saying, but not everyone has huge amounts of space to put down many solar panels... Also, last I read, I understood CoCT to say that they would not allow you to put more power into their grid than what you were using, thus getting payouts from them, like you seem to be getting was a no-no and it seems to be a bit more problematic getting connected for feedback to them, by now as well, it seems. How about some photos of your setup, specifically the solar panel side, I'm guessing you're on a small holding or at least on an acre plot... here in the Green Kalahari we are on probably 2 acres and the solar panels here (17 X 280W) are ground mounted and we are off the grid, daily production could be up to 35kWh from the panels, but you wold have to consume this as well, only one 5kWh inverter here, though...
  20. Yes, you don't want to go too high voltage wise, for the sake of cell life... higher voltage means shorter lifespan. Is this a 15 cell or 16 cell pack? If it is 15 cell, then 55V is already too high, that would be 3.66666 Volt per cell, so I assume a 16 cell battery and that would then make the 55V a 3.4375Volt cell voltage which is fine, theoretically you could go up to 3.65Volt per cell (!!!don't!!!!), but between the 3.4-odd and the 3.6-odd Volt per cell, you probably find no more than 1 or 2 % capacity at a serious detriment to cell longevity.
  21. That does not sound right, for 10 X 420W aka 4k2W + 5 X 550W aka 2k75W, I'd think daily production may be more like 45kW, at best, 115kW sounds really high, unless those other mix of panels add up to another 10kW or so, but then all of this on a city sized plot? You'd have to have 45 panels or so, needing lots of space, I'd imagine...
  22. Here's a "Make the smart switch" leaflet they included with the final/last bill, I made the switch, I'm off the grid... point is, though, their peak hours... 05:00 to 10:00 and again 17:00 to 21:00... not too many solar installations are producing power before sunrise and after sunset, I'd imagine...
  23. Maybe @Coulomb could chime in, I think he knows the inverter better than most and may be able to say whether the Axpert MKS4 5.6 can, via CANbus or RS485 talk to the BSL BMS...
  24. @TarynR if you inverter is set to 'zero export to CT' how much does the prepaid meter register? It is possible that your CT is the wrong way around and the inverter is trying to send more power than what it should, to try and get no reading from the CT and thus actually exporting to the grid... ?
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