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PsyCLown's Achievements

  1. I meant 2 strings of 8x 490W. The clipping of the amps I do not think will be an issue, I do not need the peak output - I need more consistent output and more output as the run rises and sets - this will be far more useful and beneficial for me, so the additional panels would be welcome, although the difference is likely negligible. Will help over time as the panels start to age and degrade.
  2. So if I were to run 2x strings of 10 panels in a 5S2P configuration, based on STC parameters it would be 248v and considering the likelihood of reaching peak output being quite low, let's say I were to clip 2A to 4A that would be around 500W to 1KW roughly and only if I am reaching close to peak power output from the panels in which case I hope I would be generating at least 7KW+ at this point with the clipping which should be sufficient and not something to worry about. This would also allow for 20 panels which means more power being generated earlier on in the day and later on in the evening when the sun is rising and setting and more power being generated during the winter months as well which is crucial for me - need to try reduce electricity bill each month and usage is quite high from early in the morning so the additional panels will help and also help later on as they age to produce a reasonable amount of power still.
  3. Clipping the amps would mean less output (watts) though, so bit of a waste. For interest sake, does the Sunsynk have any protection regarding the 500V DC limit? Would it trip or go into a protection mode or are you then in the danger zone and at risk and your warranty void and you hope everything continues to work until it breaks? Thinking more along the line of if cold weather hits and leads to the voltage creeping upwards. Although, the voltage and amps would both be affected by temperature and I believe generally they are both often lower than the stated specs. So whether one decides to run say 9x 540W panels in series or bump it up to 10 panels and do series-parallel, the likelihood of the amps or voltage being an issue is unlikely, based on the fact that typically the amps and volts are lower than what is published.
  4. Thanks to @Leshen for the call. So the main limit being 500V DC input, so allows more a few more panels to be installed safely. @Tariq I am in Joburg, Fourways area. It gets cold, but not as bad as other places.
  5. Hey all, So busy looking into the solar panel side of the solar install I want to do and am busy working out the best way to wire everything up and which panels to go with. I would prefer to use fewer higher powered panels versus more smaller powered panels, so leaning towards panels which are rated between 490W and 540W. The inverter will be an 8KW Sunsynk inverter, so in terms of specs to be looking at would be the following: Solar Input Max power input – 10400W Max V DC input – 370V (100V~500V) Max current input – 18A + 18A MPPTs – 2 MPPT Range – 125~425V So there are 2x MPPTs which can make life a bit easier. Max current is stated as 18A, however I recall it being increased with newer software / firmware. I think to 22A? Is anyone able to confirm this? @Leshen I think you mentioned this in another post somewhere on the forum. As far as I understand, the ideal MPPT range for best efficiency is between 125V and 425V? Max DC input is listed at 370V but states upto 500V in brackets. So just want to make sure I understand this, the voltage of the panels should never exceed 500V - a consideration is to calculate for cold temperatures as that will increase the voltage from the panels. I worked on cold temps of -5C which I feel is a rather safe figure to work on. However what does one want to try aim for? Between 125V - 425V or try keep it at / under 370V? Difference between the two panels spec wise (STC) is minimal, the 490W panels has slightly lower Voc of 45.33 vs a Voc of 49.45 on the 540W panels. Imp is 12.90 for the 490W panel and 12.97 for the 540W panel. Now with either of these panels I cannot run parallel as we're then looking at over 25amps which is beyond what the MPPT is capable of (even if it 22A and not 18A). So the way I see it, I am forced to run them in series only? NOCT is 45C +- 2C and the Temp coefficient of Voc is -0.275%/C. So for the 540W panel it is 49.6v x 0.00275 = 0.1364 The difference between NOCT of 45C and -5C is 50C So 50 x 0.1364 = 6.82v So 49.6 + 6.82 = 56.42v for the 540W panel For the 490W panel it comes to 51.57v Now if we are working on 425v as the maximum we get 8 x 490W panels or 7x 540W panels 3920W for 8x 490W versus 3780W for 7x 540W panels. So if I went with the 490W panels I could get ever so slightly more power from them which would come to a total of 7840W when running 8 of these 490W panels. Am I missing anything? Is the math correct, is my understanding of wanting to try keep the volts below 425V correct or should I work on 500V being the maximum and anything over 425V just leading to lower efficiency (keeping in mind, we're working on the worst case of -5C, on average temperatures will be higher). If we are working on the Voc of 45.33 (STC parameters) for the 490W, no compensation for cold temps and a max DC of 425 that means I could squeeze 9x 490W panels per string, which now gives me 4410W per string and 8 820W in total. If 500V DC is the maximum and efficiency is simply reduced after 425V, then it would still be safe to use 9x 490W panels and majority of the time, the voltage should be in the efficient range of 125V to 425V?
  6. The question is, do they want a full cycle each day or how much discharge would they be satisfied with per day? If one goes away on holiday, power usage for that period won't be as high.
  7. Wow, this thread really took off, a whole 5 pages happened over the weekend. lol So warranty wise, it seems some brands are a bit more strict but I can understand why and this certainly needs to be taken into ones decision when looking at the various brands and which one to consider. Batteries play a big role in ones setup and they aren't cheap, we all know they have a limited lifespan so quite an important decision to be made. Pylontech seem to have a battery which may achieve more cycles until it reaches its end of life, the downside being one needs to have a few batteries together in order to achieve higher charge and discharge rates and possibly to ensure a warranty claim is honoured. @Boerseun @Leshen What is the issue with the US3000C batteries? I saw one of you make mention of the US3000C batteries having an issue or something? I saw the US5000 battery has a shorter warranty now. For interest sake, what other batteries might offer good value for money which would be fine to use with a Sunsynk inverter?
  8. Hey all, So I have started looking into batteries a bit for my future solar setup and have noticed the claims from manufacturers seem to vary quite a bit. In a way the total cycles a battery can handle determines the lifespan of the battery, along with a few other factors. The Pylontech US3000C seems to be rated for 6000+ cycles with a 90% DoD - which is impressive. BSL Bull Batteries are 4000+ Cycles at 80% DoD Hubble AM2 Batteries are 3000+ cycles at 100% DoD, 6000+ at 50% DoD From the above specs, it would appear as if the Pylontech US3000C has a possible longer lifespan in terms of more cycles. I suspect the rate of charge and rate of discharge will affect the battery health and lifespan though. Pylontech (US3000C) state 37A recommended charge / discharge, 74A max charge / discharge. I do not believe they are 1C batteries, just under 1.8KW from a single battery as the recommended continuous draw. Maximum in theory should be 3.5KW according to the 74A max discharge current. As you add more batteries, I assume the charge rate and discharge rate would increase too as it is being split over multiple batteries. Hubble (AM2) state 100A max discharge and 100A max charge, their batteries are 1C rated as well so can draw more power. I believe 4.8KW from a single battery, I assume continuously. BSL Bull State 30A standard discharge, 100A max continuous discharge. I believe it is 1C and therefore 4.8KW from a single battery. In terms of warranty, they all seem to be at least 60% of the battery capacity after 10 years of usage. Pylontech: "Minimum Capacity/remaining capacity in this document would be not less than 60% of the Nominal Capacity at the end of Warranty Period." Hubble: I could not find the info, but assume it would be the same. 60% at least after 10 years. BSL: "Minimum Capacity means at least 70% of the Nominal Capacity at the end of 7 years of Warranty Period. And Minimum Capacity of 10 years of Warranty Period would be not less than 60% of the Capacity at the end of 7 years Warranty Period" So now, if the claimed number of cycles is what one should achieve before the battery reaches the 60% of it capacity, it seems as if the Pylontech US3000C offer better value in the sense of longer lifespan. Not to mention you can get more usage (discharge) out of a single cycle. I am not going to do the maths as it is Friday and I am lazy, but we could in theory work out the total KWH one can in theory obtain from each battery based on their cycles and DoD % and the Pylontech would come out on top in this comparison. Am I correct or am I missing something? I would assume those 6000+ cycles Pylontech claim is with the battery being charged and discharged at it's recommended current and not the maximum which is the only catch I can possibly see. What are your thoughts?
  9. Yeah, a little pricier - although how does the setup work with 2x inverters? Do the inverters link to each other and the rest of the setup remains pretty much the same? Like the circuit breakers wont be split between the inverters and I could get a single battery pack and just connect it to one of the inverters? One thing I have absolutely no clue about is installation costs and the cost for a mount / bracket - especially considering I have a flat roof. Also what happens if there is excess power from the panels? Like say a 5KW niverter which can handle say 6KW of power. However you have panels capable of producing 8KW and on a sunny day you end up having them generate more than 6KW, what happens to the extra power? Is it a problem for the inverter? Does it just not get used?
  10. My roof is a flat concrete roof, so I think I have the luxury of being able to point the panels in any direction and at any pitch. Would it still be worth while getting 2x 5KW inverters in such a situation?
  11. Hmm ok, will likely need to speak to the installer then and see how best to set it up. Unless you guys can advise. Basically there will be a few items which draw a lot of power running continuously, aircons being one of them. If there is load shedding I am happy for electronics to not get any power. I would like the solar panels to power them during the day when the sun is out, to help reduce my monthly Eskom bill. When the sun goes down, I was thinking they could be run off Eskom's grid as to run them all off a battery will require quite a large battery pack to last throughout the night until the sun is up again. Any ideas as to what may be the best way to have it setup? I am happy for these electronics to draw people from Eskom when the panels are not working - or to drain from the battery until the batteries are drained to a certain percentage and then to take from Eskom's grid.
  12. I see, would one be able to set it so that the non essentials can only drain the battery to say 80% or 60% and then stop drawing from the batteries to save it for the essentials?
  13. Right product, right pricing, right time. One last question for now, might seem silly but I have seen some people listing their Sunsynk inverter as 8.8KW and others as 8KW in their signatures. Is it the same inverter and it is actually rated for 8.8KW or are these two different models?
  14. Ok thanks, so seems Sunsynk is the way to go then - more people using them, good support, better UI. I see Sunsynk have a web based portal / app for monitoring, is there no phone app which can be used instead? Alternatively, I assume one could access the inverters web based interface remotely via internet, provided there is internet at home?
  15. I have noticed the Sunsynk inverters seem to be quite popular. Is the Deye and Sunsynk the same inverter, just rebranded? They seem quite similar, both physically and from looking at the specs seem to be possibly the same inverter?
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