June 15, 20224 yr Hi guys. As some of you have seen I am struggling to understand things about the power loss in my installation and thinking what and what not. I am running 18 Panels in 2SP , 9 in each string. I started with 12 Elerix 380W panels. 12 in one string was to much so for a while I was running with 11 in one string. When I wanted to order 6 more , it was out of stock and I could only order Canadian Solar 375W , Canadian Solar HiKu CS3L-375MS. Then I made 2 strings with 9 panels per string. As I am a noob and installed the 12 Elerix first , I added the HiKu where I could and where I had place. So each string is configured as : 1 x HiKu + 6 Elerix + 2 Hiku again. Now, the electrical characteristics of this panels is VERY close to each other and even if I have some loss , I would not mind with 100-200W per string , but I struggle to find the rest Characteristics for the Elerix Half Cut 380Wp 120 cells: Electrical Specification EXS-380MHC-B Maximum Power (Pmax) 380W Module Efficiency 20.90% Open Circuit Voltage (Voc) 41.30V Short Circuit Current (Isc) 11.69A Maximum Power Voltage (Vmp) 34.80V Maximum Power Current (Imp) 10.92A Electrical DATA@NOCT EXS-380MHC-B Pmax [W] 283.80 Vm [V] 32.40 Imp [A] 8.76 Voc [V] 38.70 Isc [A] 9.45 Characteristics for the : Hiku mono 120 Cels ELECTRICAL DATA | STC* CS3L 375MS Nominal Max. Power (Pmax) 375 W Opt. Operating Voltage (Vmp) 34.3 V Opt. Operating Current (Imp) 10.94 A Open Circuit Voltage (Voc) 41.0 V Short Circuit Current (Isc) 11.61 A Module Efficiency 20.3% ELECTRICAL DATA | NMOT* CS3L 375MS Nominal Max. Power (Pmax) 281 W Opt. Operating Voltage (Vmp) 32.2 V Opt. Operating Current (Imp) 8.75 Open Circuit Voltage (Voc) 38.8 V Short Circuit Current (Isc) 9.36 A I know , if possible one should not combine panels in one string , but this is the situation and I go with what I have. Could this configuration make me loose 2800Watt ? Here we think PANELS ONLY , no other factors like tilt , temperature , etc, thinking pure solar panels, I am trying to find the bottleneck by elimination process. Slap me , beat me , i'm fine with that as long as I learn something Edited June 15, 20224 yr by Jaxone
June 16, 20224 yr Those panels are quite well matched, and should work well together. I suggest buying a more premium brand inverter to end your frustration. Where can one get the list of approved inverters for Denmark? Edited June 16, 20224 yr by P1000
June 16, 20224 yr Author That's what I thought also when I found the alternative to Elerix, was trying to match voltage and current as close as possible to avoid to much loss. Even if the 375w pull down a bit the 380w I don't mind loosing 100-500w from the grand total of 18 panels. I was talking with @Scorp007and he suggested me some good brands and one of them is on the approved list , like Solis. So I am pending now between Solis and GoodWe which is also on the list. I just wanted to eliminate the bad panels configuration before I go to the next step and change the inverter. Here the list : https://www.danskenergi.dk/sites/danskenergi.dk/files/media/document/Solceller_0.pdf Edited June 16, 20224 yr by Jaxone
June 16, 20224 yr Arbitrary question, but what is this spot and line on your roof at the arrows below? Could it be the shadow of something like a lamppost that could touch your lower string of panels during the day? Or is it unrelated?
June 16, 20224 yr Author It's my flag pole but it is now shading the panels , even if it would , that small shade can not cause 2500watt loss Edited June 16, 20224 yr by Jaxone
June 16, 20224 yr Even if it's not touching now, or in this image, I would still suggest to keep an eye out for it. It's already very close, and I wouldn't place bets against it touching at any time earlier or later in the day as the sun drifts over, or even later in the year. You are now near your longest days, sun is at its highest, and as the sun is about to turn South after 21 June, the shadow will lengthen with the lower angle of the sun. It might not seem that one bit of shade could cause that type of loss, but your whole lower string is electrically in series. Like pinching a straw, if you limit the current through one cell, you limit it through the panel, and if you limit one panel, then your whole string will have a lower current running through it and reduce the power output. As before, hope I'm wrong, but I think don't under-estimate it.
June 16, 20224 yr Author I will take it down No problem, for my peace of mind I will also try this. The photo is taken in the afternoon around 4-5pm , in the morning the shadow will never be there.
June 16, 20224 yr Not sure how you have these configured... for voltage delivery or for current delivery? Voltage would be 9S1P and current would be 1S9P....
June 16, 20224 yr Author 1 hour ago, Kalahari Meerkat said: Not sure how you have these configured... for voltage delivery or for current delivery? Voltage would be 9S1P and current would be 1S9P.... Not sure what you mean by 9S1P and 1S9P .. just starting my solar journey. I have them configured like I said, 2 parallel strings of 9 in series.
June 16, 20224 yr 6 hours ago, Jaxone said: Here the list : https://www.danskenergi.dk/sites/danskenergi.dk/files/media/document/Solceller_0.pdf On that list I see very few battery inverters, and I cannot find the one you have on the list. It also seems that on single phase, only inverters of 3.6kW or lower is allowed, with a few exceptions, but with a note that says "Only permitted when output is limited to max. 3680W". There is no single phase Goodwe that takes a battery, and it looks like the same thing for the Solis (although I am not 100% sure I checked them all). You might have to resort to spending a lot on an SMA system. (or perhaps a Solax hybrid) Edited June 16, 20224 yr by P1000
June 16, 20224 yr Author I was thinking to go with a 3.6kw system at first that accepts 6000W on the MPT , then buy one more when I have money to expand. Or have the damn chinese sort my firmware 😊 We tested with both 10-11-12 in series and we always come at MAX 4000Watt. Tested with 2 strings of 6 and we come 3600Watt , acceptable loss , no problem. Then we tested with 2 strings of 7 … max 4000Watt at 17.9Amps Then we tested with 2 strings of 8 … max 4000Watt , amperage 16A Then we tested with 2 strings of 9 … max 4000Watt , amperage 13A So no matter how we combine the strings the inverter is ALWAYS limited at 4000Watt.
June 16, 20224 yr 15 hours ago, Jaxone said: Characteristics for the Elerix Half Cut 380Wp 120 cells: Electrical Specification EXS-380MHC-B Maximum Power (Pmax) 380W Maximum Power Voltage (Vmp) 34.80V Maximum Power Current (Imp) 10.92A Electrical DATA@NOCT EXS-380MHC-B Pmax [W] 283.80 Vm [V] 32.40 Imp [A] 8.76 Characteristics for the : Hiku mono 120 Cels ELECTRICAL DATA | STC* CS3L 375MS Nominal Max. Power (Pmax) 375 W Opt. Operating Voltage (Vmp) 34.3 V Opt. Operating Current (Imp) 10.94 A ELECTRICAL DATA | NMOT* CS3L 375MS Nominal Max. Power (Pmax) 281 W Opt. Operating Voltage (Vmp) 32.2 V Opt. Operating Current (Imp) 8.75 based on the specs above, you should see between 8.75A and 10.92A per string, I'm thinking the limitation may be your inverter... what inverter is it?
June 16, 20224 yr Author Well,for me it is hard to believe that my panels can produce ONLY 4W Watt CONSTANTLY (with interruptions where I made various tests with the strings , stopping battery charge so I can test charging also later during the day ) from 12 to 15 , while sun changed position, without somehow being capped at 4000watt. At around 14:40 I reduced the battery charging current and left BMS to manage the rest.
June 16, 20224 yr Maybe the other way to look at this is to ask what solar resources you've got available in your location, and do a comparison of what production other solar users in your area are getting. In an earlier thread it was said that you are in Europe at 55 degrees North, and that your production is probably representative of your location. I think it could have been Denmark, and as such I've used Copenhagen as a representative location. What I say here is again untested, just brainstorming along another line of thinking. You are expecting your panels to perform according to the rated power which is tested at STC - Standard Test Conditions. You can research it further, but under these standardised conditions the panels are irradiated at 1000W/m^2, at 25 degrees C, etc. etc. and only then the 380W is theoretically achievable. The other specification is the rated power at NOCT - Nominal Operating Cell Temperature / NMOT - Nominal Module Operating Temperature, and again you can research what that entails, it doesn't all apply to your circumstances, but I think the key takeaway is that this represents more "real-world" operating parameters where the panels are irradiated at 800W/m^2. If you consider the graph below, here in South Africa at around 30 degrees South, we can expect Summer irradiance that is more in-line with the standard test conditions, even higher (even though due to factors like heat we might still not see the full power output in reality). At your location at 55 degrees North, you could expect to see up to 800W/m^2 irradiance, which is more in-line with the NOCT conditions. As an example, Copenhagen is forecast to see around 700-800W/m^2 in the coming days, and these are the longest days of the year. See the link to tutiuempo: https://en.tutiempo.net/solar-radiation/copenhagen.html, and compare it to the expected power output at NOCT, or 800W/m^2 (plus other factors). It might still be your inverter or anything that causes clipping of the power at 4kW. But expecting rated power to STC on your panel set in your location might not be realistic, my guess is it's more like a realistic peak of 4500-5000W before losses due to other factors.
June 16, 20224 yr 2 hours ago, Jaxone said: Well,for me it is hard to believe that my panels can produce ONLY 4W Watt CONSTANTLY (with interruptions where I made various tests with the strings , stopping battery charge so I can test charging also later during the day ) from 12 to 15 , while sun changed position, without somehow being capped at 4000watt. At around 14:40 I reduced the battery charging current and left BMS to manage the rest. You have really been trying all one could do to get more than 4000W and closer to the spec of 5600W from your inverter. The topping of the graph Shows clearly it reaches its peak. Some people install more than max panels to get more PV early in the morning and afternoon and then you get the same pattern.
June 16, 20224 yr Author 42 minutes ago, Scorp007 said: You have really been trying all one could do to get more than 4000W and closer to the spec of 5600W from your inverter. The topping of the graph Shows clearly it reaches its peak. Some people install more than max panels to get more PV early in the morning and afternoon and then you get the same pattern. Yes, that was the idea when I installed 18 panels , not because I need the 4000W but because I can get more power in the morning and late in the afternoon. And today I have ordered 4 more 390W panels just to convince EaSun Support that it's not a paneling problem. So I will run with 2 strings of 11 Panels which should give me around 8250W. I can always move some panels on West side to catch some more late sun. But I guess this topic can be considered closed for now Thanks everyone for input and moral support
June 16, 20224 yr Author 2 hours ago, GreenFields said: Maybe the other way to look at this is to ask what solar resources you've got available in your location, and do a comparison of what production other solar users in your area are getting. In an earlier thread it was said that you are in Europe at 55 degrees North, and that your production is probably representative of your location. I think it could have been Denmark, and as such I've used Copenhagen as a representative location. What I say here is again untested, just brainstorming along another line of thinking. You are expecting your panels to perform according to the rated power which is tested at STC - Standard Test Conditions. You can research it further, but under these standardised conditions the panels are irradiated at 1000W/m^2, at 25 degrees C, etc. etc. and only then the 380W is theoretically achievable. The other specification is the rated power at NOCT - Nominal Operating Cell Temperature / NMOT - Nominal Module Operating Temperature, and again you can research what that entails, it doesn't all apply to your circumstances, but I think the key takeaway is that this represents more "real-world" operating parameters where the panels are irradiated at 800W/m^2. If you consider the graph below, here in South Africa at around 30 degrees South, we can expect Summer irradiance that is more in-line with the standard test conditions, even higher (even though due to factors like heat we might still not see the full power output in reality). At your location at 55 degrees North, you could expect to see up to 800W/m^2 irradiance, which is more in-line with the NOCT conditions. As an example, Copenhagen is forecast to see around 700-800W/m^2 in the coming days, and these are the longest days of the year. See the link to tutiuempo: https://en.tutiempo.net/solar-radiation/copenhagen.html, and compare it to the expected power output at NOCT, or 800W/m^2 (plus other factors). It might still be your inverter or anything that causes clipping of the power at 4kW. But expecting rated power to STC on your panel set in your location might not be realistic, my guess is it's more like a realistic peak of 4500-5000W before losses due to other factors. @GreenFieldsI would totally agree with you and your arguments IF I could see some peaks over 4000W , but looking at the PV power today during whole day , with load and no load and charge and no charge and all the configurations I have tried , the PV power is ALWAY 4000MAX !! If it would have went at 4200 sometimes or hold at 3900 or 4170 or something I would totally tottaly agree with you ... but something does not seem right to me. 4000W max with 14 panels , 4000 watt max output with 16 panels and 4000W max also with 18 panels ??? Seems a bit odd. But as I said , I've ordered 4 more panels , if the inverter will produce more than 4000W with this added to the array , I will shoot myself 😊 Edited June 16, 20224 yr by Jaxone
June 16, 20224 yr 7 hours ago, Kalahari Meerkat said: based on the specs above, you should see between 8.75A and 10.92A per string, I'm thinking the limitation may be your inverter... what inverter is it? I am with Kalahari Meerkat on this ^^^. Especially because you wrote the following. If you keep changing the number of panels and the power remains capped at the same 4KW then that strongly suggest that it is not the panels limiting the power... 8 hours ago, Jaxone said: I was thinking to go with a 3.6kw system at first that accepts 6000W on the MPT , then buy one more when I have money to expand. Or have the damn chinese sort my firmware 😊 We tested with both 10-11-12 in series and we always come at MAX 4000Watt. Tested with 2 strings of 6 and we come 3600Watt , acceptable loss , no problem. Then we tested with 2 strings of 7 … max 4000Watt at 17.9Amps Then we tested with 2 strings of 8 … max 4000Watt , amperage 16A Then we tested with 2 strings of 9 … max 4000Watt , amperage 13A So no matter how we combine the strings the inverter is ALWAYS limited at 4000Watt. What is your inverter make and model? What is the capacity of its MPPT?
June 16, 20224 yr Author 2 minutes ago, SmittySmit said: I am with Kalahari Meerkat on this ^^^. Especially because you wrote the following. If you keep changing the number of panels and the power remains capped at the same 4KW then that strongly suggest that it is not the panels limiting the power... What is your inverter make and model? What is the capacity of its MPPT? @SmittySmit Inverter is an Voltronic licensed SMV IV 5600W ,you can see the details here : Next step is to change the inverter, even if I don't use the 4KW , I would like to know that is working as intended ... yeah , I am being to picky maybe for the price I paid for this inverter but still , others have same inverter , older firmware and works.
June 16, 20224 yr 8 minutes ago, Jaxone said: @SmittySmit Inverter is an Voltronic licensed SMV IV 5600W ,you can see the details here : Next step is to change the inverter, even if I don't use the 4KW , I would like to know that is working as intended ... yeah , I am being to picky maybe for the price I paid for this inverter but still , others have same inverter , older firmware and works. Ah thank you. That thread, which I had not seen, has all the information I was seeking. I have read the other thread. To me it screams that someone at the manufacturer introduced a bug into the newer version for the firmware that you are running. I suspect they copied the setting of 4KW from the smaller inverter (as per the manual page you posted) and applied it to the firmware for the larger inverter that you have. 4KW is just too consistent of a limit for it to be a hardware failure. I am not sure if you can downgrade to an older firmware version or if you can upgrade to a newer version that has the bug fixed. If you are running the very latest firmware then you will have to log a bug via a support call with the manufacturer explaining all the tests that you performed with the different number of panels.
June 16, 20224 yr Author 1 minute ago, SmittySmit said: Ah thank you. That thread, which I had not seen, has all the information I was seeking. I have read the other thread. To me it screams that someone at the manufacturer introduced a bug into the newer version for the firmware that you are running. I suspect they copied the setting of 4KW from the smaller inverter (as per the manual page you posted) and applied it to the firmware for the larger inverter that you have. 4KW is just too consistent of a limit for it to be a hardware failure. I am not sure if you can downgrade to an older firmware version or if you can upgrade to a newer version that has the bug fixed. If you are running the very latest firmware then you will have to log a bug via a support call with the manufacturer explaining all the tests that you performed with the different number of panels. This is what I have done for the past 2 weeks ... fighting with EaSun I write an e-mail , they answer after 2 days ... I reply within 10 minutes... they answer next day or next 2 days ... this is going to take a while but hopefully will be solved before I buy a new inverter.
June 16, 20224 yr 2 minutes ago, Jaxone said: This is what I have done for the past 2 weeks ... fighting with EaSun I write an e-mail , they answer after 2 days ... I reply within 10 minutes... they answer next day or next 2 days ... this is going to take a while but hopefully will be solved before I buy a new inverter. To me your testing with different numbers of panels seems quite conclusive, i.e., you reach 4KW and then add more panels and are still at 4KW. The suspiciously round and consistent number of 4KW which just happens to be the correct limit for the other smaller model would convince me if I were to receive your email. Unfortunately you are probably fighting a language barrier. I am not sure if using more numbers or pictures in your communication with them would help improve understanding but it is worth a shot.
June 16, 20224 yr Author Yes, I was thinking about that to , and I took some photos and videos. Will upload videos to Youtube and send them all that ... but I am quite sure they understood the problem.
June 19, 20224 yr On 2022/06/16 at 5:16 PM, Jaxone said: Well,for me it is hard to believe that my panels can produce ONLY 4W Watt CONSTANTLY (with interruptions where I made various tests with the strings , stopping battery charge so I can test charging also later during the day ) from 12 to 15 , while sun changed position, without somehow being capped at 4000watt. At around 14:40 I reduced the battery charging current and left BMS to manage the rest. This looks like your MPPT is maxing out on Amps or watt. Here is how panels with MPPT work in very simple explanation. The voltage should never go over what the MPPT can handle. This will basically blow the MPPT components if you don't have protection against that, but then the protection will blow. Watt and Amps can go over, but if it does, the MPPT will discard the extra watt and Amps it can't handle. That 4kW solid line at times...thats your MPPT using the MAX it can from the panels. Basically your panels are overspecced for the MPPT. Others have asked what inverter/mppt you running, I don't think I saw the answer, but that will probably answer this thread for you. Looking at the panels you have, the GoodWe ES5048D will easily make use of your panels, in fact I have more panels than you on mine. I also have a single string with different brands and my 2nd string is purely canadian. The 2 strings actually perform nearly the same, but I do have some loss on the mixed string, around 200-400w I think at peak.
June 19, 20224 yr 26 minutes ago, Tinuva said: This looks like your MPPT is maxing out on Amps or watt. If you read all the posts, the different 4kW flatlines in his curves are for different number of panels - he tested a number of configurations that day. This is definitely a 4kW hard limit... 26 minutes ago, Tinuva said: Looking at the panels you have, the GoodWe ES5048D I agree, sadly neither the ES5048 or any of the Sunsynk Hybrids (or the inverter he currently has) is on the list for Denmark. If the list is not really important (since his current inverter is not on it) then the Goodwe is probably a good option (since it is Europe and Goodwe is now a German company). Edited June 19, 20224 yr by P1000
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