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KLEVA

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Everything posted by KLEVA

  1. Ouch, what size is your geyser? R250k will do a solar water install for an entire hospital
  2. PS: Tubes vs Flat Panel - No contest... Flat Panels are cheaper, but about 75% less efficient... I know people have their preferences, but I can prove the results as my old flat-panel is still connected (ie: I can switch between Flat Panel and Tubes), I originally also thought that the Tubes were a hype, but 4 years later I am convinced.
  3. @YellowTapemeasure - I would be happy to discuss the apparent failed installs above, or to discuss correct installs.... I am not a Plumber but an Engineer in a few fields, maybe I can spot a problem or a fix?
  4. Hi @YellowTapemeasure & Others Solar Water heating always proves a cost benefit, you start saving from the first month. You actually proved my point in the way you said your customer was happy with the solar water install. Solar Electricity is awesome, and I wouldn't change my attitude towards it, but solar electricity is expensive and the cost/return is no where near viable. It is only us dedicated freaks that keep trying. However Solar Water heating has reached a point where the cost (internally) outweighs the Municipal/Eskom price... I repeat, I love playing with Solar Electricity and spending money way beyond what I can ever recover on it, just to play. The only viable consumer form of saving at the moment is Solar Water Heating... We may get better later...
  5. Hi All I have a 48VDC 200Ah Gel Battery solution that got completely F#$^&* during the floods in KZN (admittedly because I had to push them beyond specs, way beyond). ie: I screwed them up. I am looking for a new/second hand LiPo battery solution for between 7.4 and 20kWh (Can only charge solution up to 20A) Ideally a 9.6kWh to 14kWh LiPo solution... New or s/hand Budget is around 30-40k max
  6. Hi I first want to re-iterate (since my blogs are now missing from this Forum) - Solar Water heating is a far cheaper, enjoyable and less maintenance than any Solar Electricity installations. If this is your first foray into solar, then please, please, please, try solar water heating first - it will prove so many of the concepts, before you get dissapointed by the limitations/expense of solar electricity/power. (I know you came to this forum initially trying to save money, or keep youself going during loadshedding, but bear with me). Solar Water heating is almost a breeze to configure and enjoy. And I will give you some small cost advise below to get the absolute best out of it: You will need a solar geyser - If you don't have one, it can cost nearly 2x the price (more likely 1.5x) of your existing geyser. This is not something you can avoid. Although there are some places/plumbers that will advise that you can install solar water without a solar geyser and adapt it to your normal geyser... They are extremely less effective or just complete scams. [Price - About R14k for 150l] No matter how you try get convinced to use a flat panel design (older style), insist on an evacuated tube installation - The advantages include the efficiency, and the fact that if your geyser gets too hot during summer, you can easily unscrew a few tubes yourself without a plumber. [Price - About R15k for 12 Tubes] Purchase a geyser temperature and/or solar monitoring system to regulate. While I have a lot of issues with design and some forms of timer regulations, there is only one product that will ensure optimisation - The GeyserWise Max (careful, needs to be the Max to control a small pump - see below). I both hate and appreciate this product at the same time... Ugly as hell, no aesthetics (so hide in a cupboard if you can), and the timer is very restrictive especially about days of the week. [Price - about R1.1k] No matter what even the most brilliant plumber on the planet says - Thermosyphon will not provide enough speed or transfer to the geyser - You need a pump! If you took my advise above, then the pump power (on/off) can be attached to the Geyser Wise Max. [Price - about R1.4k] Ok, so based on the above pricing for just a 150l geyseryou are feeling like you are in for a R30k+ installation - SCARY! There are ways to do it cheaper and to do this over time, and there are many things you have available probably already in your home which will reduce the cost... But I want to compare it to your costs and the cost of Solar Electricity... After this fairly pricey installation above, you still can't find a solar electricity installation cheaper (Don't worry, I will wait for you to search and try)... You might have made a big capital outlay, but it will save you about 60kW+ on your electricity bill per month... Dependent on what you pay per month per kW and what your usage is, this outlay could pay off very quickly (2-3 years) - Solar Electricity will not come close, with nearly a 20 year ROI before you gain. This does not mean that I discount Solar Electricity, I just think that starting with Solar Water Heating is just a far more "bang for buck" starting point. Please search for my other posts regarding Batteries which will explain the almost exponential cost for Solar Electricity. Solar power (or any other source of energy) is awesome, but we need a place to store it... A Geyser makes it easy as we only want hot water.
  7. As an aside - Nothing to do with advise above... Due to the floods and lack of power in Pinetown for days, I thought I would put my batteries under bit of pressure for a day or 3... Big mistake - I had the optimal and thought I could do better... Popped 5/8 of my 200Ah AGM batteries by dropping too low and then overcharging - Took a possible 20yr set of of AGMs down to 3 years lifespan, now they are F#$%^&* PS: KLEVA is now trying to find 9kW+ LiPO batteries
  8. Have a 1500 Induction stove - This hits 6A or 1500W/hrs for such short periods that as long as you not pushing the power it is quite happy with the small very temporary loads. It also works quite well on my chinese 1500W invertor that fails to provide anything else with close to 1000W. Apologies - You are correct, my brain was working on 3kVA on my system at home - So my math was bad. At full draw 5kVA is about 22A of 220VAC, 3kVA is about 13A.
  9. Hi I hope none of my suggestions contradict @Coulomb - He is the expert with the Axpert However I would like to share my expertise with a very similar setup and propose some slight modifications. 1. Setting 02 - With your batteries, I would say 20A is sufficient if just dealing with SA Load shedding. Gel is slightly/similar in characteristics to the older Lead/Crystal (battery motors, alarm batteries, etc), but it need a lot more current before trying to boil the battery insides. This is based on the fact that you have 2 banks of 48V 200Ah. This is close to Coulomb settings, but might prevent premature expiry of the batteries by charging them slower. 2. Setting 26 - 100% agree with temp issue raised above, however due to way most invertors work they generally don't use this kind of setting often (although the Axpert does get a bit more aggressive - too often). Batteries need occasionally to be charged at slightly higher rates/voltages than normal - My thoughts that once a month is sufficient, but this is my opinion. The reason is to remove certain buildup within the battery and improve performance. I would leave this setting close to 57.4VDC for standard Lead batteries, but can go up to 58.8. 3. Setting 27 - That is far too high for an Axpert with ANY batteries - Float should always be between 12.5 and 14.4 per battery, no matter what type used. 12.5 is far too low and will eventually allow "crud" to form inside batteries, needing the 26 setting above. But setting too high (near 15V) will just keep boiling the battery and possibly start a fire if you get a slightly compromised cell... Keep this closer to a reasonable voltage like 13.5VDC per batt (or 52-54 VDC on the Axpert) 4. Setting 29 - 48 to 49VDC is reasonable if you want to keep your batteries safe. Mine were set to 50, but a sudden draw would trip the Axpert, so eventually set to 48. 5. Setting 13 - Nobody can advise you on this one - It is just experience in your environment. Just make sure this setting is not lower than setting 27 (1/2 a volt below) or you will get unexpected hops between power/non-power modes. I prefer charging slower and not pressurising my batteries, they are very expensive to replace. I had a similar setup to yours, but used cheap batteries and nearly burn't my house down. Batteries are almost the most important part of your system, they have to be able to store the power you need, but also need to last. No matter the tech, if you abuse the batteries, you will have an expensive trip into solar. I have made one or 2 of my solar battery setups last 15years and still working with same Lead Acid, but it needs care. So, take care of the batteries and get decent or maintain the ones you have. All settings on the Axpert, or any other invertor, need to take care of this... Invertors and Panels are relatively cheap, batteries aren't.
  10. Hi @Z100 & @CJE Apologise for coming to this conversation late, I only get to check the forum when I get a gap... 1. @Z100 - The after hours draw of 2000W/hr is excessive for a small place. If you are running your place like a small holding and needing equipment to provide for animals, then I understand, but a small household can easily get away with under 500W/hr when off-grid. You might have some large power items that need investigating, or you haven't converted some of your basics to be "off-grid" friendly. 2. I have a different estimate based on the consumption you presented - and it will end up being far more expensive than you anticipate if you can't cut down elsewhere: 2.a. You need an Inverter capable of 8kVA or better under load 2.b. If you need to supply at least 3kVA when desired or sometimes constantly for about an hour, then you HAVE to go top of the range that can charge as quickly. Standard Lead Acid/Lead Crystal and many others would get destroyed under such constant high loads, no matter how many you acquire. 2.c. You will need (based on Lead Crystal - LiPO would be more expensive, but a better option) at least 72,000kW available for just 24 hours (your figures). That is either 9 x high end 9kW Pylontechs (LiPo), 32 200Ah batteries, Lead Crystal or equivilent 200Ah - This is a MASSIVE outlay for a small place, and we haven't even discussed panels yet. 2.d. Your invertor and panels would need to be able to charge this system, so this would require an invertor capable of providing at least 9000W/h to the batteries on good sunny days, and as many solar panels to provide that... At 400W/Panel that is at least 23+ panels (not too huge, but this is only optimal on sunny days - look at closer to 30) 3. Your expense is not on Panels or Invertor - It is how to store the power for later use. You can get cheap invertors to supply 8kW/hr, you can get 30+ panels for R2400 a pop, but your storage is going to kill your budget, and that is only for 24hrs. 3.a. Batteries are your deadliest cost. They have to store and provide power so they have to be big. At nearly R5k per decent Lead Acid/Lead Crystal - this is about R160k that might need replacement every 5 years. LiPo will run you closer to R200k. 3.b. You will need to double your battery cost if you need to go closer to 48hrs without sunlight. Unless you are willing to spend close to a Million rand just to get off grid, this is not viable. Solar electricity is still very expensive compared to Municipal/Eskom costs. My suggestions are: 1. Reduce EVERY other power draw, no matter how small. LED globes EVERYWHERE; Stop the kids using the Kettle every 20 minutes; Make sure that unness items are definately turned off when not needed; Use a generator for Power Tools if only intermittently used (even look at a gas powered or gas conversion to existing); There are so many things you can change before going the solar route. 2. If you can reduce your overnight power usage to under 1000W/hr then you might find solar economically viable (slightly), but from what you have presented so far a solar installation is not economically viable. 3. Economics aside, as you are still prepared to spend this kind of money to get off grid properly, then you have to do things properly and not on the cheap. Definately go the Victron route with a recommended Victron installer. They can not only give you the best product, but will also (usually) provide the best advice.
  11. I am old school (and also a Windows guy more than Linux): Firstly, I apologise if I am assuming more experience than you have, I have gone into a lot more detail below that might not make sense and I will be happy to assist if you don't follow. 1. You are trying to detect an input from some kind of signal - Preferably an electrical signal that would be more reliable than a network signal (I have solutions if you can get me some kind of network input from somewhere, but I assume not otherwise you could have built a script/api to receive) 2. The simplest signal is a relay on the input power to trigger a signal to a device (Windows/Mac/Pi/etc) to trigger another relay. This machine needs to have a small bit of intelligence to either ignore multiple signals (up/down) in a row and a few small other rules. 3. If your 10 Linux machines support Power On, then the process is very simple Example: 1. I use a small EEEPC Windows 7 machine, permanently up unless power off for 24hrs+. 2. That Windows PC has 2 USB devices (obtained from internet at minimal cost) - A 4 relay trigger, and a 16 point input device that detects voltage (both in 12VDC range) 3. Using a small bit of programming, I scan the inputs and react on those. As an aside: If you have some programming skills, you don't even need any of the above and just query the Axpert directly via the USB and then make sure you are not send the shutdown and startup queries for fluctuations in power. If interested, and you have a Windows machine nearby (sorry, my scripting and code on Linux is nearly 25 years old), I can write something to do this (at a cost, I am employed by a development company & run my own). All the Axpert USB queries and information is on this site and is freely given by user Coulomb on this site and others, so you just need a program that can do this for you. If most of this is not understandable, then again I apologise for assuming your experience. am happy to help as much as I can, this is a task I do for many clients, especially when the general UPS software does not support their needs. An Axpert is just a glorified UPS (Yes, I had one when starting my Solar experience).
  12. Sorry, I have looked for spec docs for Generator input, but nothing is specified... Maybe borrow a cheaper 3-5kVA from someone you know and try - Worst case scenario it just wont work, you shouldn't damage the invertor as it will either use it or not. PS: 5kVA 3kVA is just under/close to the 16A limit of a normal plug, so a high quality extension cord can be used if you intending on drawing that much during Load Shedding... Even with my server room (600W constant), we can fit below 1000W during load shedding with all lights (including external), TV and Accessories, 3 Computers/Laptops all running. Max 5-7A even if cooking on induction stove.
  13. The LuxPower has a Generator input, so it should be as simple as connecting the output of the generator to the input of the LuxPower. Also, if generator and LuxPower are in same vicinity then a breaker shouldn't be ness as the Generator should have it's own. The specs for the generator input should be in the LuxPower docs - Most "cheaper" generators in SA, don't always output what they say they can, so make sure your Generator outputs enough for the LuxPower minimums. Especially check the ranges the LuxPower needs as far as Hz, Voltage AC, Amps (or kW / kVA), and lastly if the LuxPower needs a Sine Wave input for the Generator (otherwise it wont recognise that there is any power coming in). IE: You will need to buy a Generator in spec for the LuxPower - But connection should be very simple from there.
  14. @PicHopper - If they live in a security village then there is a good chance they have a Garage, Laundry Room, or some similar room where this can be installed. SANS10142 (Electrical excluding Solar) does have certain rules, that the Solar SANS (forgot the number) also has to follow. So the electrical portion is not the issue, if the electrical side is conducted correctly. One of the minor issues with Batteries is that they do need ventilation, I simply put a large 12v fan on one duct (inward near floor) and one on another duct (outward near ceiling) to ensure airflow - like a computer cabinet does. Normal batteries (without electronics) have no problem sitting outside, just avoid major temperature changes - use wood blocks instead of laying them on concrete floors, put at least some kind of cover over them with ventilation holes that will limit rain / minor ice. If in an area that gets below -4C often in winter, then I just wouldn't. Avoid places with direct sunlight. Installation on the outside near the coast is problematic for corrosion reasons, but inland this is no longer a problem. But will still use a small sealed shed as advised above. The invertor, even one with IP65 or better, I would still try find a place indoors. It can get damn hot inside those boxes, so use additional ventilation, and keep out of direct sunlight.
  15. Oh, last thought - Is your submersible pump definately 3phase, and not maybe just using one phase of a household 3 phase supply. It must be quite big if using 3 phase, so if you can send specs of the motor as well.
  16. Hi & Welcome 1. Is there a way you can draw a picture of your anticipated solar -> 3phase invertor -> pump switch/float switch -> pump, or even of your current setup, without solar panels? 2. Will the 3phase invertor be connected to batteries? If not, what will the batteries be connected to (to use power)? 3. How far away are the systems (batteries to pump switch/float switch)? Assume they must be close if the installer is suggesting a manual changeover switch? Now some of my thoughts: If the installer seems to think that a manual changeover switch can be used, then there is definately an automated solution that can be built. For simplicity I use an old laptop to control my automation, because I am a software developer, but there might even be a purely manual solution... Using a few car relays and at least one signal from your float sensor (stealing a bit of power from one or more of the batteries - so getting a battery balancing system will help ensure you don't have imbalances), you can easily set up a small electrical setup for all the triggers you need. You may have to get a Victron charger (I say Victron cause the are the best, but not cheap) to control the flow to your batteries and convert some of the high voltage DC to charging AC. There is no way this is an impossible task, it just might not be cost effective. So provide what you can and lets see what we can suggest with more info.
  17. There are a few things to take into account and all need qualified people: There is a new 2017 SANS code for Plumbers that specifically related to Geyser installs... Horrified me initially, but I can see the point. A blender valve is now compulsory - This connects the cold and hot water "exits" to your house and limits the max temp through pipes to +- 60 degrees max You need an intake vacuum valve, some non-return valves, cut-offs, pressure release valves and a whole host of things we never need to worry about before I am not a plumber so please bear with some of this advice: No matter the size of a Geyser (unless attached to 3 phase and completely different for industrial purposes), you shouldn't need anything more than a 4kW element (even up to 400l) Correct as above, GeyserWise (all versions) are limited to a 4kW output. Is there any chance that the might have connected a second geyser to the same electrical line? Since I am often off-grid, but still need electrical power to my geyser sometimes, I try use a 1.5kW or 2kW element for short periods so that my batteries don't get killed If the water to shower is cutting of alone, make sure there is no pressure loss between systems, and more importantly make sure the shower pipe is connected to the same/same place as where the working taps are connected Geyserwise Max systems should have a pump connected on the Panel side, but this also sometimes needs a "one way" valve if the geyser is at a much lower level than the panels (can happen even with a bad thermosyphon setup) Suggestions: If you can disconnect your solar panels & Geyserwise from the system for a day or two via valves: See if the problem still exists, this could indicate another issue not related to Solar. Good luck Regards KLEVA
  18. Have been doing a lot of electrical vehicle tests, and we don't care if we get beaten by human athletes. But it is extremely important that a vehicle can behave like a small diesel turbo. That's our benchmark - do 80km up Fields hill, and maintain 110kms on a freeway - very small requirements for an electric car, but nothing has achieved in the SA environs/availability. We are still working when we have time away from our employment, but hopefully can eventually present something from our side project.
  19. As above, it is municipality dependent - However generally they don't like it (money and electricity management) Cape Town and surrounds - It is legally required to register your solar installation and provide them with a CoC, if it is any way shared with the grid supply to your home or business Other areas - Whilst you can be a bit off the radar, feeding back to the grid is highly discouraged by almost every municipality as it makes their electricity planning very difficult If you keep your solar setup "off grid" most of the time and don't try feed power back to the municipality, then (at the moment - although the law may change in future) you are in the clear. So if you want to feed back, then you need to get approval from municipality. Note: This is just legal implications, I know many that feed back to the grid ignoring municipal implications - your call
  20. Hi Vasann Price is a little high, but I am interested. If you are in KZN I would like to inspect. Contact me on 083 5579832 Regards
  21. To expand, and some may fight me on this: My roof panels weren't earthed, even though I live in a lightning area. It worked well until we started adding/changing stuff in my solar setup My inverter is definitely earthed otherwise neutral doesn't work The 2 earths are isolated, but a big lightning strike might jump the gap I did add a 3.2m galvanized (not copper as normal) private earth, but I placed this within 1m of the Neutral earth later Personally, I don't believe in earths outside home/business for safety... To me any earth is a risk as it allows lightning to flow in areas it should have never been, and to take the shortcut through people that are grounding themselves in false belief
  22. SANS10142 and the supplementary solar SANS code insist on earthing. However some practicality comes to mind - If any part of your solar system can EVER be earthed to Neutral wire of your mains input, then DEFINITELY earth your equipment... Preferably to the closest spot near your input earth and definitely as low as possible as far as resistance. This may seem like common sense, but putting one side of a household earth on one side of a home and other earths on the other are going to create a differential voltage and subsequent current trying to get to each other. Despite what you think, voltage is not the killer of people and electronics - it is the current that kills (PS: that is why an earth leakage switch works on current not voltage). To reduce current flow in things (people, stuff and electronics) the closest path to ground needs to be considered. A thick copper wire is great, but if there was no exit in the first place, then you might actually be making things worse by earthing stuff that didn't need earthing. I am not saying don't earth stuff, but understand where the power will go... An earth wire that goes direct to your DSTV might not be the best choice... Try set it to the shortest route to your incoming electricity box, and even hard wire it to the negative wire (in SA systems negative and Earth are the same) If a system is completely isolated from any "electrical" earth then DONT earth your solar equipment, The reason for this is that ungrounded equipment is not a current path to ground, so you will avoid damaging equipment unnecessarily. However do test that your equipment is not grounded through its connections to everything else. If you are unsure, then ground the panels via a conduit (strap, wires, etc) together but then connect a ground either on your incoming ground via the Neutral bar, or drop a 5m earth bar as close as possible to any nearby earth bar close to your incoming municipal power, No installation is the same, so I can only provide some suggestions above, but hopefully that helps. Lightning never works as predicted, so it sometimes doesn't matter the precautions... your kit is fried!
  23. As per @Beatabove, I did exactly the same on my old Axpert 10kW, bugger the regulations. It worked and stopped any floating earth issue in my case. The concern is more whether you can trust the the municipal N/E is actually earthed if you are "islanded". Despite being certified and knowledgeable with various SANS codes, and hearing all the rules and regulations, my personal thoughts are as follows: * Ground/Earth your Municipal supply yourself (properly to make sure it is valid) as close as possible to your incoming supply (ie: Assume Municipality is unEarthed) * Wire your Earth connections to that common point (before invertor so N & E are common throughout your home and to the invertor) * Unless the Nuetral from the Municipality suddenly becomes live, this will stay a common ground/Earth, so bond the 2 together at that point. * If the Municipal Earth becomes live for some wierd reason, then the Voltages will be in relatively minimal distances, or you will end up in a floating 110V. (In which case start fighting with them about reperation if stuff blows up!), but seriously the normal invertor would just shut off. * Almost all invertors would have already switched over due to the bad incoming voltage and will switch back to "island" mode, so your local E & N would still be bonded, and isolate you. Then at that point your E & N are completely common, any variance can be traced internally to devices and will still trip the 30mA limit on your DB. This is the cheap and nasty solution, but also understand that whatever relay system you try put in place will still take a few milliseconds to kick in. Not just equipment damage can occur, but also severe 110VAC could go through something/someone in that time. My thoughts are to bond them permanently as close as you can to the municipal input and inverter output. My personal thoughts are just bond the input and output N & E together unless your system hates it, but at least bond the output of the invertor always back to E. *** DISCLAIMER: These are my thoughts, please test each step properly. What works for my previous setups might not be suitable for your situation and installation. A qualified Electrician locally should confirm or deny my logic, and you will need a CoC anyway. The above information is my personal thoughts and not a qualified recommendation, consultation with a local master electrician is still recommended.
  24. @GreenMan I will check, I think I can find a few Pi3's and Pi2's (about 3-4) that are unused. Not sure of models. Will PM you once I get details about exactly which might be available.
  25. Hi @PETER12 I have the software for the Imeon 3/6 (via USB connection). Not sure if that will work? You would also need to get a code/date from an Imeon installer to get access to advanced settings (I can't provide that). Give us a bit more detail on the Imeon system you have and others may also be able to assist.
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