July 14, 20169 yr Are these your specs? http://www.voltronicpower.com/files/ds/AxpertMKS_DS.pdf I.e. Maks 600w array Open Circuit 75v Max Current 25A
July 14, 20169 yr 1 hour ago, Dejavus said: Hi again, I am at the final phase of this and have opted to double the battery bank to reduce the DOD to maximum of 25% I have done my calculation and they only really need to use battery for roughly about 10 hours. SO I am now buying 4 x 12v 205AH US battery and 6 x 200W mono panels. (I intend to add more later) Axpert 3000KVA MKS inverter. IS there any special way to connect the panels to utilise the panels to the fullest. attached is the specs from the proposed panels. Thanks in advance. It's always best to get get as close to the MPPT's max Volt rating as possible. i.e. in your case, connect 2 panels in series since your panels are 35Voc - although it might be a bit too close to the MPPT Voc, so test it out first. i.e. in your case
July 14, 20169 yr Author 38 minutes ago, The Terrible Triplett said: Are these your specs? http://www.voltronicpower.com/files/ds/AxpertMKS_DS.pdf I.e. Maks 600w array Open Circuit 75v Max Current 25A Mine is the one here the Plus Model which support max 1500W array output
July 14, 20169 yr Lekker man!!! 6 x 200W mono panels connect them: Series: 3 x panels = 106.5 volts Open circuit, Axpert is 145v so your are good. Then parallel: 2 strings. So you have 14.04amps @ 106.5volts = 1495.26watt array. 4 x 12v 205AH US battery = 24v = 410ah bank At 10% charge rate you need +-41amps - Axpert can go UP to 60amps on solar. Sure some of the other guys will add more wisdom here to ensure you are on the right track, that I got it right, but all seems to be spot on! Well done! EDIT: I like the 2w standby and 98% efficiency of the MPPT. 90-93% of the inverter, not bad at all. And the 10ms transfer times, I like.
July 14, 20169 yr Author 21 minutes ago, The Terrible Triplett said: Lekker man!!! 6 x 200W mono panels connect them: Series: 3 x panels = 106.5 volts Open circuit, Axpert is 145v so your are good. Then parallel: 2 strings. So you have 14.04amps @ 106.5volts = 1495.26watt array. 4 x 12v 205AH US battery = 24v = 410ah bank At 10% charge rate you need +-41amps - Axpert can go UP to 60amps on solar. Sure some of the other guys will add more wisdom here to ensure you are on the right track, that I got it right, but all seems to be spot on! Well done! EDIT: I like the 2w standby and 98% efficiency of the MPPT. 90-93% of the inverter, not bad at all. And the 10ms transfer times, I like. Aren't you a rock star..
July 15, 20169 yr @The Terrible Triplett You are almost 100% correct just one calculation error 7 hours ago, The Terrible Triplett said: So you have 14.04amps @ 106.5volts = 1495.26watt array. Cant use the Voc volts for this use Vmax (6x200w panels only 1200w) 7 hours ago, The Terrible Triplett said: EDIT: I like the 2w standby and 98% efficiency of the MPPT. 90-93% of the inverter, not bad at all. And the 10ms transfer times, I like. Do I see a conversion?
July 15, 20169 yr 10 hours ago, Dejavus said: IS there any special way to connect the panels to utilise the panels to the fullest. attached is the specs from the proposed panels. I would connect your panels in two strings of 3. You will have a higher voltage but well within the specs for the Axpert plus. At higher voltages your cable losses will be kept to a minimum. Remember fuse your individual strings using a combiner box or MC4 Y connectors. Since you want to add more panels at a later stage I would go with a combiner box with 12A solar fuses. Good luck with the install and we would like to see photos when you're done.
July 15, 20169 yr 2 hours ago, viper_za said: Cant use the Voc volts for this use Vmax (6x200w panels only 1200w) True, but I used my experiences for on a test on a 200w panel, on a cool sunny day, I above well 200 watts. 2 hours ago, viper_za said: Do I see a conversion Nope. Truth be told, this model Dejavus got, is the first one that I saw that made me sit up and take note. Has all the markers I look for.
July 15, 20169 yr 34 minutes ago, The Terrible Triplett said: True, but I used my experiences for on a test on a 200w panel, on a cool sunny day, I above well 200 watts. Yes on certain days you might see more, still you cant use Voc voltage in the calculation. This is the voltage the panels give with nothing connected. 35 minutes ago, The Terrible Triplett said: Nope. Truth be told, this model Dejavus got, is the first one that I saw that made me sit up and take note. Has all the markers I look for. http://www.bonanzatech.co.za/index.php?id_product=7845&controller=product Not even for this retail price? R7800incl VAT
July 15, 20169 yr 56 minutes ago, viper_za said: Not even for this retail price? R7800incl VAT Nope. I have what I need thank you.
July 15, 20169 yr Author I would connect your panels in two strings of 3. You will have a higher voltage but well within the specs for the Axpert plus. At higher voltages your cable losses will be kept to a minimum. Remember fuse your individual strings using a combiner box or MC4 Y connectors. Since you want to add more panels at a later stage I would go with a combiner box with 12A solar fuses. Good luck with the install and we would like to see photos when you're done. Having looked on eBay here, seems it's quicker and faster to get the mc4 y connectors for now, seems anyone will do is that right? The combiner box I found also came with a 10a fuse, would it be okay to just change the fuse inside the box? Sent from my LG-H850 using Tapatalk
July 15, 20169 yr HI Dejavus yes you could just swop out. 10 A might also work but you may get nuisance blowing of fuses on hot days.
July 16, 20169 yr 18 hours ago, Dejavus said: Having looked on eBay here, seems it's quicker and faster to get the mc4 y connectors for now, seems anyone will do is that right? The combiner box I found also came with a 10a fuse, would it be okay to just change the fuse inside the box? Sent from my LG-H850 using Tapatalk Where are you? I can send you MC4's and fuses. 12A work very nicely in this case.
July 16, 20169 yr Author Where are you? I can send you MC4's and fuses. 12A work very nicely in this case. That is most certainly kind of you sir! But I am in the UK. Sent from my LG-H850 using Tapatalk
July 16, 20169 yr It may be a good idea to get some loose MC4 connectors from the same supplier that you get the combiner box or MC4 Y connectors from since sometimes different makes of MC4 connectors do not fit into one another. You don't want to find out in Nigeria that all you kit does not clip together as it should.
July 17, 20169 yr Author On 7/16/2016 at 9:15 AM, Chris Hobson said: It may be a good idea to get some loose MC4 connectors from the same supplier that you get the combiner box or MC4 Y connectors from since sometimes different makes of MC4 connectors do not fit into one another. You don't want to find out in Nigeria that all you kit does not clip together as it should. That would be a deal breaker certainly.
July 17, 20169 yr Author On 7/14/2016 at 11:02 PM, The Terrible Triplett said: Lekker man!!! 6 x 200W mono panels connect them: Series: 3 x panels = 106.5 volts Open circuit, Axpert is 145v so your are good. Then parallel: 2 strings. So you have 14.04amps @ 106.5volts = 1495.26watt array. 4 x 12v 205AH US battery = 24v = 410ah bank At 10% charge rate you need +-41amps - Axpert can go UP to 60amps on solar. Sure some of the other guys will add more wisdom here to ensure you are on the right track, that I got it right, but all seems to be spot on! Well done! EDIT: I like the 2w standby and 98% efficiency of the MPPT. 90-93% of the inverter, not bad at all. And the 10ms transfer times, I like. Many thanks for the above, just thinking out loud here..in order to store more energy what if I decided to go down the route of 8x 6v batteries to arcieve my 24V and connect in parallel to achieve 480AH power bank as against 410 bank, how would this affect this calculation and also, is there any drawback in this option as I read somewhere about the point of connecting multiple batteries could be point of failure.
July 17, 20169 yr It is always preferable to have a battery bank made up of a single string of batteries over a battery bank made of parallel batteries. If you do have multiple strings make sure the cables connecting the batteries of a individual string my be the same length for every string. Parallel battery strings are parallel pathways for current and you want the resistance and therefore current flow to be even between the strings. Your brother (boet in South African slang), the electrical engineer, should be able to explain or look at information on the web. Each string needs to be connected to low resistance busbars and the inverter connected to the bus bars.
July 17, 20169 yr What Chris said, try and steer clear of parallel banks where possible, not that it is always possible, but try as hard as you can. So your question on 6v connected in series to get 24v is spot on, but instead of connecting in parallel, rather get 4 batteries with the AH you need. Also look at the 2v monsters, they are even larger ah, still connected in series. Only rule to adhere to, bar the parallel connections, your inverter must be able to charge the bank at 10% of bank's AH. So on solar charging, if you go for say a 600ah bank, we must just make sure the panels and inverter combination can give you 60amps on solar for 5.5hours per day to ensure the bank can be re-charged. Not that you need to do it every day, but just when you have to, then all is still within spec. Then you can sit back and relax, loads of spare AH, capacity to re-charge if at 50% with no sweat, system then just works day in and day out, year after year.
July 26, 20169 yr Author One more thing guys.. Install is planned for this weekend and there is talking about grounding and Lightning arrestor. Can you knowledgeable people advice on this on this please.
July 26, 20169 yr This ca 3 hours ago, Dejavus said: One more thing guys.. Install is planned for this weekend and there is talking about grounding and Lightning arrestor. Can you knowledgeable people advice on this on this please. This can get technical, as you need to conduct lightning tests. But, basically, put a ground spike in the ground and run an earth cable on the mounting structure and make sure it touches every panel as well. Lighting will take the shortest path possible. It gets technical when you need todo an earth continuity test to make sure that the earth spike is earthed properly. sometimes you need to go deep, 2m+ and sometimes you need to put a couple spikes in the ground. Every building is different, and areas have different conductivity as well. For the Lightning arrestor, you can either go cheap and install a Class 2 "surge arrestor, they're about R900. Or you can do the right thing and install a "Class 1 & 2" lighting + surge protector. They're rather expensive though - R4.5k+ http://za.rs-online.com/web/p/surge-suppressor-units/7838736/ Here's some more info on the topic: https://www.dehn-international.com/pdbRes/DE_EN_Web/671/404725/Artikelnummer-pdf/404734/900065.pdf http://www.ee.co.za/article/lightning-surge-protection-rooftop-pv-systems.html http://www.surgetek.co.za/files/saltek_full_pv_catalogue.pdf http://www.sinetech.co.za/select-surge-protection.shtml
July 30, 20169 yr Author Hi All Again, So installation is currently on going now and the installer engineer has just advised me that the Axpert MKS PLus 3KVA inverter (Hybrid) does not have a built in battery equalizer feature although I have bought the HA02 battery Equalizer/balancer but he insist I need a solar charge controller which will equalize the battery? He said I have 3 Options: 1. Buy another Seperate Invert and seperate Solar charge Controller 2. Use AGM battery instead of FLooded Battery US2200 battery 3 Buy a Seperate MPPT Solar charge controller (This defeats the purpose of going Hydrid) I am in a bit of a pickle . I need advise from the experts. Note: Axpert Manual shows Flooded battery Options Under Battery Settings (default is AGM) could it mean if Flooded is selected there is no need for a seperate equalizer
July 30, 20169 yr Yes a similar discussion is here: http://powerforum.co.za/topic/785-battery-experiment-advice/?page=2#comment-13533 48v bank is tricky to split into 12v of 24v batts to equalise using chargers that can do it. I for one had 12v then 24, with a 12v charger. Splitting the bank to equalise is not an option for my anymore. Plus, equalizing can take a few hours, depending on battery SOC, so to do it batt for batt is not viable, and very inconvenient, even dangerous if you connect the wrong thing at the wrong time. Using a controller with a panel change over switch is an idea noting that to change over under load can be fatal, so it must be a planned equalisation day, where the panels are changed to power the controller, and not the inverter, and then back to inverter, never under load! A PWM controller is by far the cheapest option and I know for a fact a Morningstar Tristar45amp PWM controller has the ability to equalise on demand, +-R2500 for one, by pressing a button. But in discussing the option I realised that it is not as easy as that. The panels and the controller must match the battery bank, and a PWM has limits ito array. So only option in most 48v banks and large arrays is a MPPT which pushes up the price drastically for such a controller. So I have a feeling you are stuck, option 2 is the cheapest option. EDIT: Me, I prefer option 1, after returning the Axpert.
July 30, 20169 yr Wait, you have 24v system!!! Go and check here if the panels will match the 24v Morningstar Tristar45 PWM controller : http://string-calculator.morningstarcorp.com/ If they match, then you have a change over switch installed between panels to either feed the Axpert inverter or the Morningstar controller. So evening parents switch over to Morningstar, press the button and let it do it's thing. Once it is completed, switch Axpert off, change panels back, and switch on again. NEVER switch under load ever. Been there done that once by accident.
July 30, 20169 yr Author 17 minutes ago, The Terrible Triplett said: Wait, you have 24v system!!! Go and check here if the panels will match the 24v Morningstar Tristar45 PWM controller : http://string-calculator.morningstarcorp.com/ If they match, then you have a change over switch installed between panels to either feed the Axpert inverter or the Morningstar controller. So evening parents switch over to Morningstar, press the button and let it do it's thing. Once it is completed, switch Axpert off, change panels back, and switch on again. NEVER switch under load ever. Been there done that once by accident. Many thanks for your help, so just to clarify, this cannot be used without a separate Solar Charge Controller with my current Flooded battery setup. Option 2 would sarcrifice the Longitivity of prolonging the battery bank. This is still a learning process for me and I would not repeat this when I want to do my own install.
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