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Cef

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Cef last won the day on July 4

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  1. Sorry @Reecho. It is only for ES series. As I do not have an inverter from another series, it is impossible for me to reverse engineer and do the necessary tests. Regards !
  2. Yes. Of course. Equations based on Peukert's law or modified Peukert can be used. It is what the Victron BMV and other battery meters use to obtain the "Time to Go" expressed in hours. By also adding a "coulomb counter" accumulating or subtracting the amperes entering or leaving the batteries, a software SOC calculation can be performed in parallel to that reported by the BMS or Goodwe alone. There are many things that can be done .. That is something basic and very important and it is strange that Goodwe does not incorporate it in the PV Master. It remains for later. As soon as I can, I will modify the labels of the D.O.D. Since the values are reversed as you and fixames noted. Thanks.
  3. Ooops !!! Thank you for reporting this latest version bug. I'm going to check that!
  4. Hi ! Version 3.10 is available in the download area. I added features suggested by users @Beylie and @Pietpower which I found very useful. Let's now look at the other major factor that influences power balance and why it is rarely "0". The concept of efficiency. All energy losses that occur in the inverter are considered system losses. In the case of DC to AC conversion, no converter can achieve 100% efficiency. This means that the output power (AC) is not as high as the photovoltaic (DC) input power. The efficiency of the inverter generally varies between 95 and 98%. The efficiency of an inverter indicates how much DC energy is converted to AC energy. Some of the energy can be lost as heat and some reserve power is also consumed to keep the inverter in powered mode. The general efficiency formula is Inv_effic (%) = (Pac / Pdc) x 100 Pac = Power in alternating current Pdc = direct current power The efficiency of the inverter depends on the inverter load, solar irradiance and temperature as the most determining factors. 1. Goodwe in its specification sheet reports peak efficiency (maximum efficiency) which indicates the performance of the inverter at the optimum power output. These data show the peak for a particular inverter and can be used as a quality criterion. Goodwe reports = 97.6%. In general, inverters report this maximum efficiency under normalized conditions, this is an irradiance of 1000W / m2, Temperature = 25º Celsius, but very rarely an Inverter like this works throughout the day, for that reason and since the Efficiency varies With the Inverter's Workload, it is more indicative to carry out a Weighted Average under different load conditions and with Weighting Factors that depend on the Standard considered. Therefore, the second piece of information that Goodwe informs us is: 2.) The European efficiency, which is a weighted numerical value that takes into account the frequency with which the inverter will operate with different power outputs. It is sometimes more useful than maximum efficiency as it shows how the inverter operates at different output levels during a solar day. Goodwe reports = 97% This is obtained at 6 different power levels for a particular inverter and is based on central European temperature and irradiance data. As in general, the highest efficiency is given starting at 30% of the work load, approximately of the maximum nominal AC output power (in the case of Goodwe, this would be fulfilled if the backup loads at a given time they are approximately 1440 watts, please note this is approximate). In other parts of the world, the weighted efficiency will be different, as you can see in this work: https://www.mdpi.com/2076-3417/10/1/201/htm The lower the inverter workload below about 30%, the lower the efficiency, that is, the more inefficient the inverter will be. In other words. IF you are powering your backup loads with 450 to 480 watts AC, Goodwe's efficiency may be slightly above 85%, which means the PV power in DC should be between 540 and 565 watts. If efficiency is not considered, the Power Balance will give you a Positive Value of 80 Watts (Contributions - Expenses). Again please. This is a rough example. This value is contemplated in "PARAMETERS" 3.) MPPT Efficiency, this value for Goodwe reports=99.9% and reflects the algorithm's ability to track the maximum power point or P - V curve at any time. This value is not contemplated in "PARAMETERS" 4.) Maximum battery (DC) TO Loads (AC) efficiency: this is the value that arises from: BatD_Eff = (Pac / Pdc_BatD) x100 Goodwe reports = 94%. This value is not contemplated in "PARAMETERS" To all this, we cannot ignore 2 Efficiency values that Goodwe does not report. These are: a) AC power conversion efficiency from grid to batteries (AC to DC). This value is not contemplated in "PARAMETERS" b) Energy conversion efficiency from PV DC to Battery Power DC (DC to DC). This value is not contemplated in "PARAMETERS" From there you will observe the complexity of the interactions that arise and that add to what we already saw in previous posts.
  5. Hi @Beylie I owe a more detailed explanation of this topic, as I promised Pietpower last week. This weekend I will try to explain what I have studied in reference to the Conversion Efficiency values of the different types that are produced in a Power Inverter and especially with the scarce data that the manufacturer that interests us gives us: Goodwe. All this to close a bit more a concept on which there is very little free public bibliography. For now and beyond the concept of efficiency and regarding your particular case. 1) The value of 72 Watts of correction you have put with a positive sign. If you put -72 in the corresponding field, your Balance between received and expended energy will give you closer to 0 for the backup load values that you show on the screen and with the inevitable instantaneous spurious fluctuations, that the smaller they are, the better they are filters in DC to AC reversing circuits. I hope it is understood. In other words, entering +72 tells the software that the value reported by Goodwe CT is wrong. And that you should always add 72 watts to the value you think you register for your critical loads. In the case of your example, I see that you have a PV value that has been corrected for efficiency (97%), so Contributions = 721 Watts (Effective Watts) Expenses = 827 Watts (reported by Goodwe CT) + 72 (Correction value reported by you) = 899 Instantaneous energy balance = Contributions - Expenses = 721 - 899 = -178 On the other hand, if you put = -72 Instantaneous power balance = 721 - (827 - 72) = -34 2) Question: - Based on which instrument do you consider this value? = 72 watts or -72 watts? Remember and read a previous post on page 2 and I have put it in the "Tool Tips" and in the "i" help that these fields are valid only if you have external instruments that give you certainty that the CT of your Goodwe_Es unit have a deviation, measuring more or less Watts, in this particular case in its essential loads or Back Up. It can also correct in case the amperage / voltage reported by the BMS is different from the one you corroborate with an external instrument (a Victron BMV - 702 for example or an electrical tester) On the other hand, it should be considered that the deviation or error of an instrument (any), seldom follows a linear or proportional relationship or function. This implies that if we wanted to be strict we should consider a different correction value (I repeat, derived from measurements with external instruments) for AC load values between 0-500 w, 501-1000, 1001-1500, 1501 .. .. and this just to give you examples. Requires a laboratory study ... To simplify the matter, I only put a SINGLE VALUE to which ALL measurements can be corrected and which should be an average value that arises from the tests that you must perform with an instrument of greater precision than the Goodwe CT. And that is the objective of the corresponding field in "PARAMETERS" For example, I check mine with an Eastron SDM230 meter at the essential loads output. I repeat. If they don't have external instruments, don't correct. Leave the fields at "0", don't worry about the absolute value (no algebraic sign) of the Power Balance, otherwise you are just guessing. This weekend with a review of version 3, I will try to explain the main source of differences which is the Conversion Efficiencies. They interest 4 and the Goodwe specification page only informs us 2. Please Install all Fonts ! ;.) Regards
  6. Well. Surely at least one of your panels gives you low amperage and that pulls your entire string down. If you look at the scheme of the system, you will see a couple of interesting data, which are the daily highs of Vmp and Amp for each chain. Good luck !
  7. Ok, about the software. 0) Install all the Fonts if you don't want the spacing of the text to be wrong .1) The accounts are fine: Don't worry about the energy balance. Analysis can be long I am far from home and I answer uncomfortably from my mobile. Next week we will. 2) Of course, it is very simple, in the next version I add a button to export to Excel Sheet. 3) I don't know what Goodwe does with the data sent by the firmware on the server side, PORTAL SEMS, but if you add the values between 14:35:00 to 14:35:59 and divide them by 60, it is almost certain that you will get what it shows: 1335 W at 2:35 pm in SEMS. 4) PV. Exactly, a much lower efficiency is observed in PV2, but are their powers symmetrical? Are they exactly the same orientation? No shadows in PV2? Are the nominal power ratings set exactly in the software settings of this thread?
  8. Interesting! Until 14:35:06 everything on your system seems to be working perfectly. You have low values with positive bias, which implies an insignificant surplus of power contributions with respect to your consumption. From that moment on, everything changes strangely. It match exactly, according to the information your BMS sends to Goodwe, when the charging poder of your batteries increases. A negative value always implies that the consumptions are greater than the contributions, but in your case it really seems like a lot. We should see the big picture of what exactly happened from then on with the rest of the variables. Could you maximize the grid and display a full screenshot of the first column after that exact time ? As for photovoltaic strings, this software show you valuable information, there is something you suspect. Why?
  9. With reference to the number that appears in Instant Power Balance, please read 10 previous posts on this page of this thread. Having configured the Goodwe for 0 Watts of Export to the Grid, and in the working modes: GENERAL or BACKUP (my main tests) Those -400 watts can't be constant! They should only be instantaneous! I have seen instantaneous values in my house of up to -500 watts exceptional in cases where there is significant consumption of both essential and non-essential loads and that all are being supported by Pv power. The moment one of these high consumptions disappears when a device in my house is turned off, I have detected that there is an instant Export peak, despite having Export set to 0, it is much higher than what the Power normally requires Inverter to synchronize the network. It is an abnormal peak. I have no explanation for this, it is what Goodwe reports and causes an instantaneous imbalance in numbers giving a below -200 watts approximately. I have also observed these values with external instruments ... but I don't want to extend this answer too much. However: If you insist it has a constant value of -400, show here a screenshot of the sector where that value is recorded. Go to the option where you look at the database second by second and scroll right to the column that says "Lost / Surplus". These are the instantaneous values of the stored energy balance. Also in this version (3.0) a field is added in "PARAMETERS" that will allow you to eliminate All ABSOLUTE values Greater than the one you write there. I originally left it set to 1000 so that each user can determine the optimal value based on at least 1 full day of registration. I have it configured in my system in: 200 This in order that these anomalous instantaneous peaks are eliminated from the Database and do not affect the averages and sums in hourly, daily, monthly kWh ...
  10. @FixAMess that's not why. The instantaneous data in Watts sent and extracted from the batteries, the Goodwe firmware informs them and sends them to the SEMS PORTAL, they simply have not designed the accumulators, that is, on the server side, the integration of the values sent in time to obtain kWh discharged or charged in batteries. In other words, it is a problem with the Goodwe software on the SEMS PORTAL and its API. The new option of the Comparative Statistics of this software, tries to solve the lack of Goodwe. Goodwe is a Plug and Play inverter, neither its firmware nor SEMS PORTAL software is intended for intermediate or advanced users. And most users are comfortable that way. One of the objectives of the development of this program is precisely to be able to know exactly what the system is doing and why it is doing it the way it does every second and little by little to develop other characteristics and capabilities far beyond the SEMS PORTAL. .
  11. Morning from South Africa,

    Thank you for the awesome work and program, here is my response to the requested page:

    "This is a most AWESOME program. I can now make sense of my PV and inverter as a solar system.

    Cef, THANK YOU for your time and effort, you are a star, your work, effort and dedication is highly appreciated.

    Barry"

    Thank you again, brilliant work and program

    1. Cef

      Cef

      Hi @Barry de Kock
      I did not receive your private message with the numerical data requested by the program to be able to generate your Hex activation key. Did you send it ?

      CEF

    2. Cef

      Cef

      User ID: barrydekock

      Hex key: 7854545F9F675D8CADA695708C06C908A87116DA0

      The expiration date is: 10/10/2100. In the Terms and Conditions window that after executing the application again, that date appears in its penultimate line along with its User Id.
      Confirm that well before pressing the confirm button.

    3. Barry de Kock

      Barry de Kock

      Thank you, 

      Everything working and loads of new information for me to look at, work out and understand.

      You are a master at this. THANK YOU

      Regards

  12. Well. The answer will not be short. I hope to be clear. Reason why I add the "corrections" in the LCD Mode -Parameters-: "Using instruments with greater precision than the Goodwe (one more decimal place) I realized that the data it delivers has measurement errors even at the level of its own resolution. " If you look at my posts, you will find the RTPhoram system. This is the one that I have used "as a contrast" and simultaneously with the same PC with the readings that I get from the Goodwe. The magnitude of these errors may be greater or lesser and this will affect what would be the instantaneous POWER BALANCE, at this moment in the development of the system. The downside of these errors is their accumulation. To obtain kWh, kWh daily, monthly, annually, the values are added and also the errors if they are not compensated with instantaneous values greater or less than 0. Therefore, what you are seeing on the SEMS Portal will follow this logic. Following the general Physical Principle of Energy Conservation, or Energy Transformation, this Balance arises from the difference between Inputs and energy outputs and must be "0" in an ideal condition, which is never fulfilled by the fluctuations introduced by the AC harmonics. Energy is not the same as Power, but for calculation purposes we are talking about electrical power. The total input power at a given moment will be: Imported grid power, photovoltaic power and battery power in discharge (the latter term is the power that supports loads or is exported to the grid). The power outputs at the same time will be: Power consumed by backup loads, power consumed by non-essential loads, power exported to the NETWORK, power to charge the batteries and power self-consumed by the inverter. As I explained in the release notes, I have determined that the value that is read live in the Backup Output (Loads_E in the following equation) includes the current self-consumption of the power inverter which is not constant, obviously according to the operating conditions. In the following equation the absolute value will be considered (without sign of the Discharge or Charge Power of the Batteries) POWER BALANCE = (Grid_I + PV + Bat_Disch) - (Loads_E + Loads_NE + Grid_E + Bat_Charg) From here then it can be understood that if you observe a POSITIVE or NEGATIVE value of the POWER Balance Value constantly above 100 to 200 watts (which is what I have determined through tests as normal fluctuations except for certain Peaks when a Sudden GRID Export) It is quite possible that one or more of Goodwe's sensors measure more or less power values. The problem is that external instruments are required to be able to know what is causing this constant difference. Due to the measurements made in the System, I did not observe important differences in the BackUp Outputs, Non-Essential Loads or in the Import / Export from and to the GRID. I detected the serious problem in the current and voltage measurements both in charge and discharge of the battery and in the STAND BY state. Due to these errors, being the SEMS Portal the batteries in STAND BY (Current = 0), it permanently showed me a load of 130 Watts: wrong condition. I could post my own corrections, but they would be of no use to you. If you do not have external measuring instruments, you will be guessing if you put values other than "0" (without correction) in the electrical parameters. I hope you understand me. Regards.
  13. Hi @Barry de Kock Thanks. It is a pleasure to share what helps me with this community from which I have learned so much. The software system DOES NOT WRITE any Data to the Goodwe. It only reads the Data that is running (live data) and part of the configuration that has been written in the Power Inverter, prior to executing this program, through the Android / Iphone PV Master / Ez Manager application from Goodwe. The appearance of the program is intended to "simulate" what the Goodwe lacks, which is an LCD Display. The RED Button, which I changed in name in this version is now called "LCD MODE". The idea is that it resembles as much as possible to a real LCD panel, as functionalities are added, these will appear successively with each press of the "LCD MODE" button. I don't know if you mean this or how to interpret the information that appears in the "LCD MODE" PARAMETERS ¿?
  14. Hi @Beylie ! You are right. In the next review I will include that Font You can search for it on the web. It is called: DS-Digital and the files are DS-DIGIB.TTF and DS-DIGIT.TTF. Regarding how to exit the system: I did it this way on purpose for now as I am in the design phase. Starting from version 3.0 I will start to record all electrical parameters in local databases, the processor workload for a single thread can increase a lot. You may need to separate it at some point in development into 2 apps. A resident that reads the data from the Goodwer and passes it to another application that displays it and that is the one that interacts with the user. As I also intend to add energy adders and statistics, this way of exiting simply prevents that it is closed by mistake and that in the future the data is not registered in the Databases.
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