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GreenFields

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Everything posted by GreenFields

  1. To each his own, and I don't think there's a clear right or wrong here. But I think @chrisc can get very close to the desired performance by just copying these exact time and percentage settings for starters, and tweak from there as and when needed. The charging power will be limited by the grid amps you set, so if you go for 100A it will be around 5kW charge rate. I'd suggest ticking the box for "Load Priority," and then for days of low sun, set a 2-hour charge in the slot 3pm-5pm. Or even set it later like a 4pm-6pm slot in summer. Ideally let it be done before peak hour.
  2. Solis hybrid inverters come in at a bit cheaper than the Sunsynk and Deye brands. Available on the Powerforum store as an example, the Deye 5kW is around R16,859 whereas the Solis 5kW is on special at R13,455. It's still not in the price class of the off-grid Axpert-type inverters though.
  3. This is fairly straightforward. On the "System Mode" screen above, select the time slot when you want to charge from grid by ticking the "Grid" check-box right next to it. However, you could do a lot more tinkering with the six time slots that are available. Play around with the start-time and end-time for these time slots so you can get an ideal usage plan for your daily schedule/needs.
  4. Personal opinion. I would just set the charge/discharge amps to the higher value, 185A. My thinking is, on a normal day your charge rate will in any case be limited by the approx 5kW of installed solar power (panel specs TBC), so the amps will naturally top out at around 100A at mid-day (less baseload) and be generally gentle on the batteries. But whenever you choose a grid-charge, you might want to replenish the batteries quickly, like in preparing for loadshedding, and then you might not want to take half the day or longer to do the charge when you could do it in 2 hrs. Rough thumbsucks. As long as the charge rate of 0.4C - 0.5C is then still within the manufacturer's recommendation and the installed wiring, etc supports it.
  5. If you're talking about the Growatt SPF 5000 ES, then I'd personally I'd look at the first string being 5 Megatron in series with 3 JA, and the second string being 5 Hyundai in series with 3 JA. But also, that's if you're satisfied to connect just 7.25kW of panels when the inverter(s) can handle more. Just a personal opinion, to be checked professionally. The disadvantage would be in that you cannot cannot effectively approach the maximum 6000W solar array that each inverter can handle, or efficiently upgrade after that, unless you use a different panel that's more closely matched to the 18A MPPT spec. In theory the additional 4 Megatron panels will mostly not quite cover charging the additional storage capacity. It's your call to check/say if it meets your needs; there's not enough info about your daily loads and off-grid/on-grid situation to form a proper opinion.
  6. Respectfully, I disagree. Don't tick Solar Sell if you are not normally exporting power to the grid. Especially if you don't have a registered system. I don't see anything obviously wrong in the settings that explains why the battery is not supplying the loads when it should. Try to eliminate everything else first. Turn of the Main Switch on the DB board, and if it's daytime, turn off the PV knobs on the underside of the inverter. It will then be operating like a UPS, disregarding any time-of-use settings, and also disregarding your CT coil. Does the battery then begin taking over carrying the loads on the backup load port, like it would in the event of an emergency or power outage? Or do you find yourself sitting in darkness?
  7. Could it be possible that your loads are all connected to the grid-port(s) of the inverter? That could be one explanation why you are not ever diverting battery power to the loads, but if you use Solar-Sell it could be that your exports are being channelled to the grid-side loads. As above, try changing your setting to "Zero Export to CT" and then un-ticking the Solar Sell box, and then see what's happening. Sorry for the repetition.
  8. Is this your master or slave inverter? Please post all system work mode and battery settings screens for the master inverter.
  9. Two issues bugging me. If you have 5 x 0.5C batteries installed, why are you seeing a 200A discharge limit and not 250A Is the Pylontech spec? Are all the batteries communicating to the inverter? What happens when you run with the battery settings in Voltage mode? On one of the screens above the power inflow and out from from the inverter doesn't match. Around 2.05kW PV, but almost nothing from battery, but then 0.98kW going to loads and 2.68kW exported to grid. Was this transient? Any chance there's a problem with the CT coil fitment?
  10. Might mean nothing. Dont' know, just speculating. I'm reading a Sofar hybrid manual off the web, and it says that "The HYD 3-6K-EP inverter has two MPPTs, which can operate independently or in parallel. The inverter can automatically identify the MPPT operating mode." And then elsewhere as troubleshooting for a PVConfig Error: "Check the PV input mode (parallel/independent mode) Settings for the inverter. If not, change the PV input mode." Is there any chance that this MPPT parallel configuration feature/setting is causing the solar power to be capped to 50% of the rated capacity by throtting the current, as if it thinks only one MPPT is connected? Even if that's not it, I'm just thinking that 50% seems so non-random that it suggests there's an inverter setting somewhere that is causing this limit.
  11. So I finally get to test my minimalist theory in real life. Because of costs at the time I had decided to install just a 5kW inverter with 2.75kW of panels and 5kWh of battery power, basically sized to carry me through daily load-shedding stints, while remaining grid-tied and rather just trading power with the grid with time-of-use. The goal was to have something more financially justifiable than going off-grid. I reckoned that if a large-scale blackout would come, I'd be able to survive with my household in limp mode - nearly normal - while it gets re-started, and still be better off than most folks. And if Eskom well-and-truly dies, then being off-grid on my own island while the country collapses is a wishful fantasy. Well that day has now come. You may have caught the news of Nelson Mandela Bay's outage due to a pylon that collapsed from vandalism and poor maintenance. While some parts of the city have got power restored rotationally, I'm in one of the areas that will NOT have any power until infrastructure is re-built. Current promises say there's a 14-day restoration plan, but we'll see. At the same time water supply is affected. My small rainwater tank is sized to carry just around a week's water supply and/or be a diversion tank for the pool. Water gets pumped normally for toilet flushing only, but if the municipal supply goes out I can sanitize and divert water to the rest of the house to cover short periods. Not great pressure on a 0.375kW pump, but better than nothing. So far so good. As long as there is enough sun, I can cover my baseload through the night, and run all other major loads by day. Food is not likely to spoil in the freezer. Hot water is supplied by thermal solar (flat plate) with an insulating blanket on the tank. A gas cooker & braai skillet are available, but I didn't trust gas availability in a crisis, and so a simple electric two-plate stove and slow-cooker are additional backups. The pool may have to suffer. But as long as the sun shines by day and some rain falls at night, I think we'll be okay. PE ExpressPower outage disrupts electricity and water supply across...Stay updated on the power outage affecting the Nelson Mandela Bay Metro. Restoration efforts are currently underway.PE ExpressPower outage: 14-day plan to repair infrastructureGet insights into the ongoing Nelson Mandela Bay power outage and its implications for residents and businesses.
  12. Maybe another dumb question, but how did you install the panels? Flat close to the roof? How much light is falling on the rear face of the panel? What's the bi-facial factor spec of this panel?
  13. This is probably the biggest factor. It sounds like you're comparing replenishing the standing loss of the guest geyser (typically 1.5kWh-2kWh radiated losses per day) to the energy of re-heating the main geyser with a heat pump after drawing out hot water and cold water comes in. Perhaps the best comparison would be to see how much energy it takes to re-heat the main geyser from cold to 60 degrees. If it takes 6.45kWh to heat 200l with a conventional element, then your heat pump should be doing the same using only about 2kWh.
  14. Can you post your graphs of power generation, loads, battery usage and grid usage, for a whole week? That is a typical day Monday-Friday, and then Saturday and Sunday. Also, what type of inverter and what batteries, how much battery capacity, are you using?
  15. Not recently, but I moved to time-of-use some time ago. Your bill all depends, as the name implies, on the time that you use power, ie. you are being dis-incentivised to use power during peak times, and encouraged to use more during standard or off-peak times. If you have not changed your usage pattern, if you are still using the majority of your power in peak times like weekdays 6-9am, and evenings 6-8pm (or thereabouts), then your bill may well be going up. Or were you referring to something else?
  16. How much are you looking to spend? I mean, you could get a 5kW off-grid inverter kit for under R30,000, and include a ready-db board. https://www.voltex.co.za/product/6-x-455w-canadian-solar-panels-1-x-5kw-luxpower-inverter-1-x-greenrich-4-95kwh-wall-mounted-battery/?gad_source=1&gad_campaignid=20598911893&gclid=Cj0KCQiAosrJBhD0ARIsAHebCNqiEv3PhQfWxI89VrqR2SUJPWFKJ0koOyaZMbc49zDoY0T4yP3pD_YaAmfsEALw_wcB Size-wise this will be plenty to meet her needs, and even allows that she could add some appliances like a two-plate stove to cook on by day, or get a kettle.
  17. What tariff are you on? If you have got a time-off-use tariff with different charges depending on the time of day, then it may make sense to run the battery down during peak hours and charge it again from the night-time or off-peak tariff. If there's no financial benefit to be had like that, then don't bother cycling the battery (in general), it will cost you some battery cycles and extra electricity costs, for no real reason. Just keep it on standby in UPS mode most of the time. Maybe just schedule a discharge to 30% or so once in a while so that the battery does not remain fully charged 100% all of the time. Try to follow the manufacturer's recommendations for charge level if available. Try to get solar panels asap.
  18. I'm making a few assumptions, and you may have to correct me or fill in the unknowns. I'm understanding that you have a 3.6kW Sunsynk inverter, the model sold in the UK with the 7kW MPPT. If so, it should have a max charge rate of 90A, or around 4.5kW. If you've been keeping your charge amps setting to 32A for fear of exceeding the grid supply, that's nothing to worry about. That would be 32A at probably 230V, or around 7.4kW. Just set the inverter's charge setting to 90A, and it should top out at 4.5kW, whether from grid or solar. Right now if you are only achieving 1.8kW of power from solar (or lack of), that's maybe understandable on account of sunlight, but experiment with grid-charging to confirm that you can reach that 4.5kW or 90A from grid.
  19. Just taking a chance or eliminating possibilities. Could you give more info about your battery setup, firstly the LiBMS-screen, what values it shows for installed capacity, and the maximum charge rate? Also, under the Battery Settings screen, can you please give the maximum charge rate that is set there? I'm just thinking from the point of view that the BSLBATT spec sheet indicates a recommended charge rate of 30A (max 50A), and you've got 3 of them, compared to your neighbour that has 4x Freedom Won batteries (charge rate 70A). The difference in charge rates of the battery banks could help explain why your solar production is being limited.
  20. From the link: Azimuth ranges from -180 to 180, where 0 is south, -90 is east, 90 is west and 180/-180 is north. Why, oh why, are they turning every convention on its head? Feels like a dystopian world where everything has an opposite meaning to what you think it should.
  21. One thing I can think of, is to be aware of the power out being 5000VA, and 4000W. ie. it's not a 5kW output, but a 4kW output per inverter. To compare the cost accurately, you have to pitch it against a 12kW single-phase hybrid. Just browsing the Powerforum store, you can get the Solis 12kW for just under R35000, and then if you shop around the Deye and Sunsynk 12kW are around R40,000 give or take depending on where you shop. There's the usual benefits of redundancy with the Victron setup, versus the simplicity and possible installation cost savings of a single 12kW. But I don't think that it's a no-brainer on the inverter cost alone.
  22. Any neighbours running cables from the same pole?
  23. I know that the question has been posed as "How do I increase my battery storage capacity," but I think it's also reasonable to take a step back and ask about the energy generation and demand first. How much energy can 3.6kW of panels even be expected to generate in Winter in Cape Town? I just popped some values into the PVWatts calculator and assumed the best-case scenario of all panels pointing North. I know it's not the case here, we're looking at a East-North-West setup, but anyways. For June the expected generation is 296kWh for the month, or average 9.8kWh per day. That's hardly enough to charge up the 10kWh of storage, and quite possibly not enough to cover consumption on top. If the real-life generation and consumption values are different, @Bran please share it, but I'm wondering whether adding a further 10kWh battery is even going to help. You'll likely be charging it from the generator all the time anyway and taking further round-trip losses. You may have to step into the realm of demand-side management. Okay, I'm not talking about AI-controlled devices, not even the more pragmatic timer-controlled transfer of loads to the daytime. Rather, using efficient appliances like a heat pump or, maybe do more cooking on gas or coals during Winter, defrosting your meat overnight in the fridge, turn your electronics off at the wall plug, or whatever you can to take load off from the inverter/battery system. If you can't add batteries or don't want to change the inverter, maybe a solar water heater will help.
  24. I wasn't going to comment, but hell here goes. I've had this type of chat also with someone who owned a thermosiphon geyser in Graaff-Reinet, so no electricity involved, but the same principle applied. Leave the heating unchecked, and at some point the water boils to the point where the geyser relief valve opens and you dump a load of boiling water. Now sure, you could have this type of split-system where you have a Kwikot geyser as per normal in the roof, and then a retrofit set of tubes, with the circulation pump powered by a small solar panel. In this scenario you could turn the Eskom feed off, and if you've over-sized the panel relative to the geyser volume, you'd have the same problem in principle of excessive heating. The same issue potentially as putting the panels directly to the AC element without a controller. Turning to the scenario here where 4x450W panels are hooked up to the 3kW geyser, consider that in summer with effectively 7 or more daylight hours you could generate up to 12kWh of electrical energy, which gets dumped straight into raising the water temperature On a 200l geyser that might be okay, but on a 150l geyser that's enough to raise the water temperature for an ambient 30 degrees C to boiling point. Even if one person hasn't had an issue in 3 years, I still wouldn't suggest it as a general solution for every household. Lots of folks could be off on holiday over Christmas, and having your geyser reach boiling point every day while you're out of town is just - well maybe nothing happens - but I still wouldn't do it. For my money, back to the original title of this thread, being about a 5kW hybrid inverter, I see the Powerforum Store is now pitching the 5kW Solis S6 Hybrid inverter on special at R11,730 incl VAT. https://powerforum-store.co.za/collections/inverters/products/solis-s6-pro-5kw-advanced-hybrid-inverter I'd start there with a 2kW element for heating by day. Around 3kW (6x550W) of panels for the 12-15kWh of daily consumption. And considering that the recent poster was asking about usage that's for the evening and also largely in the morning, I'd expand later with a heat pump for the morning usage, and 10kwh battery storage, and making the whole house more self-sufficient. All with CoC. To each his own.
  25. Considering that they are selling them only in container-sized orders, probably not. But more than that, the specs of the 450W Ultra-Light panel are wrong (CETC-435-450TR(L)/96). According to the table above, at STC the Voc=37.2V and Isc=14.3A. But if you look at the spec sheet, it's Voc=35.76V and Isc=15.66A at STC. Maybe @Powerforum Store can check and confirm. Personal 2c worth. Vmp=14.76A at STC. Basically, you won't destroy anything, but you won't get the peak power out of the panels in summer, you'd clip at around 90% of what the panel can achieve. I'd rather go for the 590W panel out of these two options, if it's for a 5kW Sunsynk. Or otherwise if you want the 450W panel, rather go for a different inverter like the Solis that takes a higher MPPT input current.

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