André Mermoud

The nominal power Pnom is the maximal output ac power of the inverter in any conditions. Some manufacturers define a maximum power Pmax , which is the maximum power attainable under specific conditions (they sometimes say "half an hour", but it is probably related to the temperature of the inverter). Now this temperature is very difficult to estimate, this would require a complete knowing of the environment of the inverter, ventilation conditions, etc. This is not done in PVsyst, and therefore the maximum power cannot be taken into account. By the way in "normal" systems correctly sized, this bonus is probably low. And in "strongly oversized array" systems, the maximum output power is detemined by the contractual acceptance of the grid, and this bonus doesn't apply. NB: perhaps in a future version, PVsyst will be able to take the Pmax value into account for inverters installed ourdoor. This will require additional specifications about thermal behaviour from the manufacturers.

In the database, bi-polar inverters are defined by the mention "Bipolar inputs" in the technology specifities box. With the bipolar inverters and in the system sizing tool, the voltages are clearly indicated with the +/- mention. The number of modules in series correspond to the full voltage (i.e. 600 V for +/-300V indications). The module Vmax should perhaps be modified. The module's datasheets usually specify that the module should not be implemented in installations overcoming 1000V. But it is not clear if this limit is applicaable to the full differential voltages in the system, or only the voltage by respect to the ground. You should contact the module's manufacturer for assessing this limit.

InvLoss Global inverter loss - This is the sum of all inverter losses. IL Oper Inverter Loss during operation (efficiency curve) - The inefficiency loss, computed according to the efficiency curve. IL Pmin Inverter Loss due to power threshold' - Loss when the power of the array is not sufficient for starting the inverter. IL Pmax Inverter Loss due to power overcharging - When the MPP power is over the input power required for obtaining the specified PNom(ac), the inverter displaces the operating point on the I/V curve in order to get exactly the required power for Pnom(ac). This IL Pmax loss value represents the difference between the Pmpp and this adjusted power. NB: The displacement is towards higher voltages. If the voltage exceeds the Vmaxmpp limit of the inverter, the inverter has to stop, and the Pmpp is fully lost. IL Vmin Inverter Loss due to low voltage MPP window IL Vmax Inverter Loss due to upper voltage MPP window - If the Vmpp is outside of the inverter's window (Vmppmin/VmppMax) the inverter will clip it to the limit value. This loss is the difference between Pmpp and the corresponding P of the I/V curve at the limit value.

You have defined Transformer losses. When connected to the grid, the transformer consumes some energy (iron losses), explaining this night negative energy. You have the opportunity of disconnecting the transfo during the periods when the inverter is OFF (in the rreality, this means a HV automatic switch on the grid).

We will organize courses as Webinars soon.

What do you mean by "3-dimentional 2-axis tracking systems" ? You can define 2-axis systems in the "Orientation" part, and for mutual shading calculations in the "Near shadings" editor.

This negative value is rather low (around 0.3% of Pmax) The simulation is performed on a complete hour, and therefore also the "Night disconnect" function. Now in for one hour the PV production doesn't compensate the iron loss of your transformer, you can have a negative balance over the whole hour.

PVsyst is developed under DELPHI, which is closely related to Windows. It cannot be run under other operating systems.

This is explained by the fact that - The mismatch loss is computed as a a percentage by respect to the STC power at each step. - The result in the loss diagram is displayed as the percentage of the remaining energy after the preceding loss. Therefore the reference is not the same so that the percentage changes between the parameter definition and the results. In your case, when increasing the Thermal loss, you increase the difference between the STC value and the remaining energy. NB: This calculation according to STC is not quite meaningful (it is an historical choice). In the future version 6 the loss will be computed by respect to the remaining energy, so that the Loss result will correspond to the specified loss parameter.

No sorry, in PVsyst you can simulate a mix of 2 orientations on a same inverter input (Orientation option "Heterogeneous fields"), but not 3. The only way (approximation) would be to simulate two orientations in a simulation with heterogeneous fileds, and perform in independent simulation with the third orientation. For doing this with this particular inverter you can redefine your inverter as 2 different devices: one with 2/3 nominal power, and another one with 1/3 (or the shares of your different arrays). In this way the mismatches between string 1+2 and string 3 will not be taklen into account; but their influence is probably not very high.

The transposition model (and therefore the gain) is highly dependent on the diffuse fraction in your meteo data. Please carefully check these values (in the Meteonorm data of PVsyst, you have 38.6% of diffuse in Bamako, and 35.2% in Marseille). The transposition values given by PVsyst are usually considered as realistic. Now we don't know how the manufacturer's data have been established.

PVsyst doesn't take the altitude correction for inverters into account. The correction - when necessary or specified by the manufacturers - is mainly related to cooling capabilities (air pressure) and results in a diminution of the Nominal outpout power. If you want to take this into account, you have to redefine your inverter with a new Pnom corresponding to your altitude (i.e. change the value, and save your inverter under another file name).

You can download the program PVsyst V 5.xx (last version) from www.pvsyst.com, and install it. It will run during 30 days with full possibilities, and then revert into DEMO mode. For getting your licence, please open our site www.pvsyst.com, and choose "Order" / "Purchase online" - You can pay directly by credit card. In this case we send you back your activation code, along with a paid invoice. - Or you can pay by bank transfer. When we receive your order, we send you back the invoice (valid 30 days), and we send the activation code as soon as we receive the payment. This may usually take 1 to 3 days.

The "Local number" is an identifier of your PVsyst installation on a given machine (more exactly a given Windows installation"). It is established by PVsyst: you cannot change it. You can find the "Local number" in the main menu "License" / "Code and Activation". You need an "Activation code" matching this "Local number" for using the program.

With version 5.xx There is a tool in PVsyst for transferring the code from one machine to another one. After installing the software on the target machine, please carefully read the "Local number" produced. Then you come back to the original (licensed) machine, open the tool ("License" / "Transfer to another machine"), which will ask for the new Local number and will deliver the corresponding code. Please note it carefully, and keep this information for the future. After that, the original machine will turn itself into DEMO mode. This procedure may be performed as often as desired. With version 6.xx In the main menu, open "License" / "Status and activation", press the button "Transfer" and follow the instructions. You will have to deactivate your license on our server, and then you will be able to reuse it on any other computer. NB: You will need your "Customer ID" for performing this transfer, which is mentioned on your invoice or the mail containing your activation key. If the computer where the license was activated is unavailable (reformatted, lost), you have to contact our administration admin@pvsyst.com, and explain the problem.

Please open PVsyst (at least once) with full administrator rights, i.e. by right-clicking the icon and choose "Run as an administrator". If this doesn't work, please ask your IT specialist to do so (with full administrator rights).

You can obtain a contextual Help from anywhere in the software, by typing F1. You also have some little buttons (orange questionmarks), which provide more specific information. NB: There is no user manual at the moment. But you have some Tutorials in the help, for some guidance during your first steps in the software. Namely about: - Meteo Data, - How to create and develop a project, - 3D Construction for shadings.

In the main menu "Files", you have several options: - Export whole projects, ensures that all files involved in the project are well taken into account, - Import whole projects, which dispatches the files in the suited folders. - Import and Export Database elements, which will position the components files in their corresponding directories.

For the versions 5.xx Since version 5.2, depends on your Windows OS: - Under Vista and Windows 7: c: \ ProgramData \ PVsyst \ Data \ - Under XP and olders: c: \ Documents and Settings \ All Users \ Application Data \ PVsyst \ Data \ Now you can also have yourself delocalized the data structure anywhere else (i.e. created directory "PVsyst_Data"). The directories actually in use are listed in the dialog "Files" / "Directories" It is possible that you don't see the c:\ProgramData\ directory: see "I don't see a folder "\ProgramData\" on my machine". It is also possible that you don't find your data in the c:\ProgramData\PVsyst\Data\ directory: please see "I don't find my files in the \Data\ structure". For the versions 6.xx The data structure is normally in c:\Users\"yourSession"\PVsyst6_Data\ If you have displaced them the actual path in mentioned in the main menu of the software: "Files" / "Workspace", User workspace ... You will find a complete description of the Database structure and localization in the Help: "Technical aspects > File organisation > User data > Projects and PV components".

Under Windows Vista or Win7, this folder is always present. But it may be "Hidden". For seing the hidden files or directories in your Windows File Explorer, please: - Open "Windows File Explorer" with the administrator rights (i.e. right-click the icon and choose "Run as an administrator"), - In the menu of the explorer "Organize" / "Options of folders and research" / "Display", choose "Display the hidden Files and Folders". Under Windows XP, the equivalent location (where \admin\ and \data\ directories are stored) is c: \ Documents and Settings \ All Users \ Application Data \ PVsyst \ Data \

The files you have created or modified are normally stored in the following folders: - Under Vista and Windows 7: c: \ ProgramData \PVsyst \ Data \ - Under XP and olders: c: \ Documents and Settings \ All Users \ Application Data \ PVsyst \ Data \ Now with Vista and Win7, if you don't have Windows rights for writing in these areas from your user session: when the program attempts to write on this area, Windows delocalizes these files and places all files written by the program in the special location: c:\ Users \ User \ AppData \ Local \ Virtual Store \ ProgramData \ PVsyst5 \ Data The files in \Virtual Store\ are treated by the program as if they were located in the PVsyst folders. NB: This is not a comfortable situation. You should obtain Windows writing rights for this folder.

You should obtain the Windows writing rights on the working folders of PVsyst, i.e. - c: \ ProgramData \ PVsyst \ Admin \ - c: \ ProgramData \ PVsyst \ Data \ For making these folders writable: - open the Windows file explorer by right-clicking the icon and choose "Run as an administrator". - Right-click the folder \Admin\, choose "Properties" / "Security", and here you can manage the writing rights on this folder for your session. - Do the same with the \Data\ folder, and everything should be ready for using PVsyst. If you don't see the folder c:\ProgramData\PVsyst\ , this is a hidden folder. If you don't succeed, on very well protected machines, you have to ask your IT specialist for doing this. NB: Under XP, you should do this from a User session beneficiating of Administrator rights.

When clicking the button "Report", I obtain the following message in French: "Aucune imprimante sélectionnée". Sorry, this sometimes arises even if you have correctly installed printers (it is a Windows problem), and I don't know why. You can try to download the free tool PDFCreator (to be installed as a printer): http://www.pdfforge.org/products/pdfcreator and select it as default printer. To my knowing this works in any case. And after that every printer may again be recognized as default printer. Mysteries of Windows...

Normally for creating a PDF document you have an option in your printer list, managed by Adobe Reader. However sometime the Adobe PDF tool doesnt work, and I don't know why (probably an internal security parameter not understood by PVsyst). You can download the free tool PDFCreator (to be installed as a printer): http://www.pdfforge.org/products/pdfcreator To my knowing this works in any case.

When defining and exiting a 3D shading scene, PVsyst checks that it is compatible with the rest of your system. In your case: - You have not yet defined the system (modules and inverters) - In the "Orientation" part you should define a tilt of 22° and an azimuth of around -26° NB: when developing a new system (calculation version) in PVsyst, you are advised to always begin by a basic system, and then add the complications step by step. The definition of the 3D scene is a secondary step, it should be done after the definition of the "Orientation" and the "System" parts.