First of all you have to connect to OS ONE. You must therefore be at the installation site with a computer/tablet/smartphone to connect locally to the inverter. If you are unable to connect to OS ONE, please update via USB stick (See Procedure).
Once this is done, you can go to the "About" section on the top right and click on "Search for a software update". If an update is available, a "Download" button appears. You must then click on the button to launch it. The duration of the update depends on your internet connection.
Make sure you have enough bandwidth to load a 100MB file. In case of doubt, it is better to have with you a USB key equipped with the update program (See Procedure).