Eurard Posted May 18, 2023 Share Posted May 18, 2023 (edited) Hi All, I need some feedback from yall, please. So I need to do that all important upgrade to "CORRECT" panels but am going to be hell bent in making a mistake again. My setup lends towards 18A, single MPPT up to 500V. So my choices are series string up to 500V VOC. 1. Canadian Solar - 555W (or 545W) - Both in the 4k region, but need 10 of these. 5550W 2. Jinko 620W - 4.5k but only need 9 - 5580W 3. Seraphim - 550W - 3.7k need 10, but they are also bifacial and the 550W is the full front only output. By raising the panels slightly off the roof, might add a bit more from the under side. 5500W (If I raise the panels by 10cm, I might get upto 5940W (10% added from Rear) - Max from rear is 30% - 702W per panel (will never get this on a roof so just going with a maybe 10%) All in all the overall prices are from 37,000 - 41,500, so not a massive difference, just need to know which you deem is the best choice. Im leaning towards these three, but dont know. I do know that Seraphim has a plant in SA, Jinko has featured on the PVEL top solar panels each and every year since the list started 8 years ago, and Canadian has very high regard with people, 4th below the likes of LG, etc. So all three these are respectable. Oh and I see the Raystech panels looks like rebrands, especially the Seraphim brand. They are a bit cheaper than Seraphim itself. Edited May 24, 2023 by Eurard Quote Link to comment Share on other sites More sharing options...
Bobster. Posted May 18, 2023 Share Posted May 18, 2023 57 minutes ago, Eurard said: Oh and I see the Raystech panels looks like rebrands, especially the Seraphim brand. They are a bit cheaper than Seraphim itself. Probably Raystech and Seraphim are buying from the same factory, but Seraphim either buy panels that have passed stricter QC tests or are charging more because their brand name begins with an S... McGuywer and zsde 1 1 Quote Link to comment Share on other sites More sharing options...
GreenFields Posted May 18, 2023 Share Posted May 18, 2023 Personal opinion, my 2c would be to keep it simple if you have the space available, keeping the panels low to the roof surface, unless there's a real need to use bi-facial panels. I have a few Jinko panels that are giving me no trouble at all (under 1 year old admittedly), but I understand Canadians are also respectable in brand. But I don't think it's a straightforward choice between option 1 and option 2. You didn't specify the model or panel specs, but I'm reading between the lines that you may be pushing the limit on the 500V Voc, like with 10 Canadian solars at 49.3Voc, or 9xJinko at 55Voc. That would leave basically no margin of safety in the event of spikes. Personally I'd look around for the Canadian Solar HiKu7 Mono 600W panel or similar, with Imp=17.2A, Voc=41.3V, so you could use 9 or 10 in series while keeping comfortably within the Voltage 500Voc limit, and under the 18A limit. And maybe compare those specs to the inverter's Isc limits at the same time, to make sure it can handle the panel's 18.47A short circuit current. All to be checked professionally, and at your own risk. PsyCLown 1 Quote Link to comment Share on other sites More sharing options...
Eurard Posted May 18, 2023 Author Share Posted May 18, 2023 (edited) 34 minutes ago, GreenFields said: Personal opinion, my 2c would be to keep it simple if you have the space available, keeping the panels low to the roof surface, unless there's a real need to use bi-facial panels. I have a few Jinko panels that are giving me no trouble at all (under 1 year old admittedly), but I understand Canadians are also respectable in brand. But I don't think it's a straightforward choice between option 1 and option 2. You didn't specify the model or panel specs, but I'm reading between the lines that you may be pushing the limit on the 500V Voc, like with 10 Canadian solars at 49.3Voc, or 9xJinko at 55Voc. That would leave basically no margin of safety in the event of spikes. Personally I'd look around for the Canadian Solar HiKu7 Mono 600W panel or similar, with Imp=17.2A, Voc=41.3V, so you could use 9 or 10 in series while keeping comfortably within the Voltage 500Voc limit, and under the 18A limit. And maybe compare those specs to the inverter's Isc limits at the same time, to make sure it can handle the panel's 18.47A short circuit current. All to be checked professionally, and at your own risk. 100%, I will ensure I put a breaker in to limit on the 500V before it hits the inverter. And yes max 18A in, so don't want to go over that as well. I already have 15A fuses on + and - for Solar. Currently I have only a 400V breaker in. Edited May 18, 2023 by Eurard Quote Link to comment Share on other sites More sharing options...
Scorp007 Posted May 18, 2023 Share Posted May 18, 2023 36 minutes ago, GreenFields said: Personal opinion, my 2c would be to keep it simple if you have the space available, keeping the panels low to the roof surface, unless there's a real need to use bi-facial panels. I have a few Jinko panels that are giving me no trouble at all (under 1 year old admittedly), but I understand Canadians are also respectable in brand. But I don't think it's a straightforward choice between option 1 and option 2. You didn't specify the model or panel specs, but I'm reading between the lines that you may be pushing the limit on the 500V Voc, like with 10 Canadian solars at 49.3Voc, or 9xJinko at 55Voc. That would leave basically no margin of safety in the event of spikes. Personally I'd look around for the Canadian Solar HiKu7 Mono 600W panel or similar, with Imp=17.2A, Voc=41.3V, so you could use 9 or 10 in series while keeping comfortably within the Voltage 500Voc limit, and under the 18A limit. And maybe compare those specs to the inverter's Isc limits at the same time, to make sure it can handle the panel's 18.47A short circuit current. All to be checked professionally, and at your own risk. So good to read a good and correct answer from someone who knows how things work. +1 Quote Link to comment Share on other sites More sharing options...
Eurard Posted May 18, 2023 Author Share Posted May 18, 2023 1 hour ago, GreenFields said: Personal opinion, my 2c would be to keep it simple if you have the space available, keeping the panels low to the roof surface, unless there's a real need to use bi-facial panels. I have a few Jinko panels that are giving me no trouble at all (under 1 year old admittedly), but I understand Canadians are also respectable in brand. But I don't think it's a straightforward choice between option 1 and option 2. You didn't specify the model or panel specs, but I'm reading between the lines that you may be pushing the limit on the 500V Voc, like with 10 Canadian solars at 49.3Voc, or 9xJinko at 55Voc. That would leave basically no margin of safety in the event of spikes. Personally I'd look around for the Canadian Solar HiKu7 Mono 600W panel or similar, with Imp=17.2A, Voc=41.3V, so you could use 9 or 10 in series while keeping comfortably within the Voltage 500Voc limit, and under the 18A limit. And maybe compare those specs to the inverter's Isc limits at the same time, to make sure it can handle the panel's 18.47A short circuit current. All to be checked professionally, and at your own risk. Quick one, give me some stats from your Jinko's: Also output in summer and what you are seeing now, I assume they are also roof mounted. This will give me an idea of what to expect, and whether to maybe tone it down a tad. Quote Link to comment Share on other sites More sharing options...
Eurard Posted May 18, 2023 Author Share Posted May 18, 2023 How about maybe going with only 8 x 620w Jinkos? Quote Link to comment Share on other sites More sharing options...
GreenFields Posted May 18, 2023 Share Posted May 18, 2023 43 minutes ago, Eurard said: Quick one, give me some stats from your Jinko's: Also output in summer and what you are seeing now, I assume they are also roof mounted. This will give me an idea of what to expect, and whether to maybe tone it down a tad. My panels are not a direct comparison, it's a totally different output of panel, I just used that as a reference for the brand expectation. I know you're considering the Voltages and putting in protection, but I wouldn't risk it all the same. Even if it never causes damage, too many panels will also take you further away from the optimum operating range. If you can give the make and model of your planned Jinko panels, and also the make and model of your inverter, then one can double-check what could be a good match. Quote Link to comment Share on other sites More sharing options...
Eurard Posted May 18, 2023 Author Share Posted May 18, 2023 (edited) 6 minutes ago, GreenFields said: My panels are not a direct comparison, it's a totally different output of panel, I just used that as a reference for the brand expectation. I know you're considering the Voltages and putting in protection, but I wouldn't risk it all the same. Even if it never causes damage, too many panels will also take you further away from the optimum operating range. If you can give the make and model of your planned Jinko panels, and also the make and model of your inverter, then one can double-check what could be a good match. Sweet, okay I decided to play it safe and only go for 8 panels. This is still 4960W, and VOC of 444V, well under the 500. What I wanted to know is what is your wattage on panels and what do you get roughly this time of year? The jinkos are the JKM620-78HL4 Inverter 120VDC to 500VDC 1 mppt - max 18A Normal operating voltage - 240VDC Rated power 6000W MPPT 100A Edited May 18, 2023 by Eurard Quote Link to comment Share on other sites More sharing options...
GreenFields Posted May 18, 2023 Share Posted May 18, 2023 Please specify the make and model of the inverter also. I just don't recognise these input specs off the cuff. For example, if it says that the normal operating Voltage of the MPPT is 240VDC, I know you say that it takes up to 500VDC, but I just don't want to suggest something that's far off the sweet spot, that might for example not generate as much as you'd like it to, even if it never blows up. I'd rather like to check the datasheet of the inverter itself. Quote Link to comment Share on other sites More sharing options...
Eurard Posted May 18, 2023 Author Share Posted May 18, 2023 (edited) 38 minutes ago, GreenFields said: Please specify the make and model of the inverter also. I just don't recognise these input specs off the cuff. For example, if it says that the normal operating Voltage of the MPPT is 240VDC, I know you say that it takes up to 500VDC, but I just don't want to suggest something that's far off the sweet spot, that might for example not generate as much as you'd like it to, even if it never blows up. I'd rather like to check the datasheet of the inverter itself. Think the model is a FS-1007. Like the one in the pic here Edited May 18, 2023 by Eurard Quote Link to comment Share on other sites More sharing options...
GreenFields Posted May 18, 2023 Share Posted May 18, 2023 With massive disclaimers, because I don't have first-hand experience with this inverter, but I'll stick with my original 2c, especially noting that the nominal operating Voltage is 280V, that it's best to stick to a panel set that will give you maximum power output at a higher level of current, and at a lower Voltage to allow you to get closer to the inverter's nominal spec. Scorp007 1 Quote Link to comment Share on other sites More sharing options...
suds7162 Posted May 18, 2023 Share Posted May 18, 2023 7 hours ago, Eurard said: I will ensure I put a breaker in to limit on the 500V before it hits the inverter. Someone please correct me if I'm wrong, but breakers don't break on voltage, they break on current? A 400V breaker that's subjected to 500V won't break, it'll burn. Pumba 1 Quote Link to comment Share on other sites More sharing options...
Eurard Posted May 18, 2023 Author Share Posted May 18, 2023 (edited) 3 hours ago, GreenFields said: With massive disclaimers, because I don't have first-hand experience with this inverter, but I'll stick with my original 2c, especially noting that the nominal operating Voltage is 280V, that it's best to stick to a panel set that will give you maximum power output at a higher level of current, and at a lower Voltage to allow you to get closer to the inverter's nominal spec. Okay, just got home. 8 x Linko 620s. With VOC and drop in volt when load kicks in should get to close Operating. Also closed my eyes and got another 5.4kw battery, now Im done. Edited May 18, 2023 by Eurard Quote Link to comment Share on other sites More sharing options...
Eurard Posted May 18, 2023 Author Share Posted May 18, 2023 4 minutes ago, suds7162 said: Someone please correct me if I'm wrong, but breakers don't break on voltage, they break on current? A 400V breaker that's subjected to 500V won't break, it'll burn. Yes, Im an idiot lol. Not a breaker lol. Quote Link to comment Share on other sites More sharing options...
Eurard Posted May 19, 2023 Author Share Posted May 19, 2023 @GreenFields - Any chance you can feedback on my question to you earlier? What I wanted to know is what is your wattage on panels and what do you get roughly this time of year? Quote Link to comment Share on other sites More sharing options...
Eurard Posted May 22, 2023 Author Share Posted May 22, 2023 Okay so installed the new 8 x 620w Jinkos, pulling 12pm 4.2kW. With the 11kW backup, this guy is now less dependent on grid. So relieved. 8kva 6000w inverter 11.5kw battery 4960w JinkoSolar Total cost ... Less than 100k. zsde and mzezman 2 Quote Link to comment Share on other sites More sharing options...
Eurard Posted May 24, 2023 Author Share Posted May 24, 2023 (edited) Hi, Thought I will give you an update: So we are over the moon. Yesterday was a mega bad gloomy day until roughly 12pm in the afternoon, but even then we managed to pull higher than our previous panels. Total Eskom usage (units - Kwh): 20/05 - 9.32 21/05 - 10.93 22/05 - (New panels installed and switched on at 12pm) - 2.00 23/05 - 5.25 - Bad half of the day, at most pulling 1.4kW, and geyser eskom additional usage was 1.3kW x 3 hrs 24/05 - 0.51 (Perfect Winter day, not a cloud in site) the usage is because of running a Geyser, 2.7kW, Charging batteries and a washing machine all at the same time. Evening usage: Eskom live from solar drop till 8pm. Then onto battery as I physically load shed myself until 10am the next morning. Battery SOC - Full at 90%, 53.6V - starts charging at 7:15am (Solar strong enough) - Voltage at start charge 52.8V. Now we are in anyway because of the old system very careful users of electricity, but this will relax in time to come. Solar output of out of the 4960W rated power, registered Voltage (Amps between 3 in the am and up to 13 midday, then dropping again): 6:15am - 119V 7:15am - 285V 8:15am - 427V 9:15am - 432.4V etc. Our main load starts at 9am, with washing, laundry, geyser etc. So Voltages lower under load. Under load the Voltage lies between 300-380V, which is acceptable against the normal MPPT operating Voltage. Keeping the Eskom switch on (CBI astute), is also using 50w, which I am really thinking of just switching off, but the usage is to tiny I might just keep it on. My battery charge from AC is set as 2A, but I am really thinking of actually just setting the charging priority to Solar only. As I don't want to use Eskom to charge the batteries at all after Solar drop in the late afternoon. Issue is when it is gloomy bad day and I am not home, Eskom can at least now charge it a bit when solar drops. In a nutshell my schedule is as follows: 12am - Battery 7am - Solar starts charging battery 10am - Eskom switched on 17:00 - Solar drops 20:00pm - Eskom switched off, running off battery With above looking at an electrical bill of R300 pm odd, and yes, we can go 100% off, but not needed, as this is exactly where we wanted to be for now. What lies ahead? 20kW total Battery East and West solar for just 1-1.5Kw am and pm extra (max 6 panels, even 4 might be good enough) So there it is, will give an update again in a week or two, for some averages. Edited May 24, 2023 by Eurard zsde 1 Quote Link to comment Share on other sites More sharing options...
Scorp007 Posted May 24, 2023 Share Posted May 24, 2023 2 hours ago, Eurard said: Hi, Thought I will give you an update: So we are over the moon. Yesterday was a mega bad gloomy day until roughly 12pm in the afternoon, but even then we managed to pull higher than our previous panels. Total Eskom usage (units - Kwh): 20/05 - 9.32 21/05 - 10.93 22/05 - (New panels installed and switched on at 12pm) - 2.00 23/05 - 5.25 - Bad half of the day, at most pulling 1.4kW, and geyser eskom additional usage was 1.3kW x 3 hrs 24/05 - 0.51 (Perfect Winter day, not a cloud in site) the usage is because of running a Geyser, 2.7kW, Charging batteries and a washing machine all at the same time. Evening usage: Eskom live from solar drop till 8pm. Then onto battery as I physically load shed myself until 10am the next morning. Battery SOC - Full at 90%, 53.6V - starts charging at 7:15am (Solar strong enough) - Voltage at start charge 52.8V. Now we are in anyway because of the old system very careful users of electricity, but this will relax in time to come. Solar output of out of the 4960W rated power, registered Voltage (Amps between 3 in the am and up to 13 midday, then dropping again): 6:15am - 119V 7:15am - 285V 8:15am - 427V 9:15am - 432.4V etc. Our main load starts at 9am, with washing, laundry, geyser etc. So Voltages lower under load. Under load the Voltage lies between 300-380V, which is acceptable against the normal MPPT operating Voltage. Keeping the Eskom switch on (CBI astute), is also using 50w, which I am really thinking of just switching off, but the usage is to tiny I might just keep it on. My battery charge from AC is set as 2A, but I am really thinking of actually just setting the charging priority to Solar only. As I don't want to use Eskom to charge the batteries at all after Solar drop in the late afternoon. Issue is when it is gloomy bad day and I am not home, Eskom can at least now charge it a bit when solar drops. In a nutshell my schedule is as follows: 12am - Battery 7am - Solar starts charging battery 10am - Eskom switched on 17:00 - Solar drops 20:00pm - Eskom switched off, running off battery With above looking at an electrical bill of R300 pm odd, and yes, we can go 100% off, but not needed, as this is exactly where we wanted to be for now. What lies ahead? 20kW total Battery East and West solar for just 1-1.5Kw am and pm extra (max 6 panels, even 4 might be good enough) So there it is, will give an update again in a week or two, for some averages. As was pointed out earlier. Your 500V breaker will only trip over 63A which you will never see. Also your MPPT is at risk as the voltage can be over 500V and no trip but and expensive smell. Quote Link to comment Share on other sites More sharing options...
Eurard Posted May 24, 2023 Author Share Posted May 24, 2023 (edited) 2 hours ago, Scorp007 said: As was pointed out earlier. Your 500V breaker will only trip over 63A which you will never see. Also your MPPT is at risk as the voltage can be over 500V and no trip but and expensive smell. 8 x voc 55.55v ... explain the risk? Thats why I went down to 8 and not 9 panels, you probably missed that. Edited May 24, 2023 by Eurard Quote Link to comment Share on other sites More sharing options...
Scorp007 Posted May 24, 2023 Share Posted May 24, 2023 31 minutes ago, Eurard said: 8 x voc 55.55v ... explain the risk? Thats why I went down to 8 and not 9 panels, you probably missed that. Just read my post slowly? Nothing to do with 8 or 9 in series. Also the post from @suds7162 Quote Link to comment Share on other sites More sharing options...
Eurard Posted May 24, 2023 Author Share Posted May 24, 2023 25 minutes ago, Scorp007 said: Just read my post slowly? Nothing to do with 8 or 9 in series. Also the post from @suds7162 Okay so put a 500v in? Explain slowly like you would a grade 1 kid. Quote Link to comment Share on other sites More sharing options...
Scorp007 Posted May 24, 2023 Share Posted May 24, 2023 1 hour ago, Eurard said: Okay so put a 500v in? Explain slowly like you would a grade 1 kid. This device does not operate at any voltage. If you get like 600V from the panels say 12-13 in series. It will still not operate and disconnect. It is rated at 500V not to get damaged up to that level. It should handle a good % over the 500V level. The main point is is serves no purpose on your system as it is a 63A current unit. This is AFAIK and I could be wrong. I passed grade 1 too long ago to know if this makes sense Quote Link to comment Share on other sites More sharing options...
Eurard Posted May 24, 2023 Author Share Posted May 24, 2023 (edited) 1 hour ago, Scorp007 said: This device does not operate at any voltage. If you get like 600V from the panels say 12-13 in series. It will still not operate and disconnect. It is rated at 500V not to get damaged up to that level. It should handle a good % over the 500V level. The main point is is serves no purpose on your system as it is a 63A current unit. This is AFAIK and I could be wrong. I passed grade 1 too long ago to know if this makes sense Okay got you, what to put in? I have two 15A fuses and also two surge protection in, with this switch. Edited May 24, 2023 by Eurard Quote Link to comment Share on other sites More sharing options...
TaliaB Posted May 24, 2023 Share Posted May 24, 2023 1 hour ago, Eurard said: Okay got you, what to put in? I have two 15A fuses and also two surge protection in, with this switch. 8 x 620wp in series = 444Voc Isc= 14.25A. Replace 63 amp dc breaker with 20 amp dc breaker as stated you already have 2 x 15A dc fuses as extra protection. What @Scorp007is saying your current rating of 63 amp dc is way too high and won't serve any purpose. Quote Link to comment Share on other sites More sharing options...
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