Firmware is the operating system for the device. Its just like the operating system for your phone or computer, and determines how it behaves.
WHY UPDATE IT?
There is no reason to update the firmware unless you have a specific need. The most common reason why you would want to do this is because some new device has come along that you would like to connect to your MultiPlus and in order for it to recognize the device it needs to be updated to know what to do. Anyone who recently bought the VE Bus Bluetooth Dongle probably needed to update their MultiPlus or Quattro in order to use it.
WHAT DO I NEED TO GET STARTED?
1. You need to know the number of the processor installed in your MultiPlus or Quattro. It is a seven digit number, the first four digits of the updated file must match the first four digits of your processor, the last three digits represent the version number. In the photo below the processor is labelled "X"
2. You need to have a way to communicate between your PC and your MultiPlus or Quattro. For now this will have to be the MK3USB interface. In the future the VE Bus Dongle will be able to do this.
3. You need to have a copy of the VE Flash software installed on your computer. You can download this from the Victron website software page
4. You need to have a copy of the new Firmware file which you can get from your Victron dealer once you provide them with the details of the device you are updating and the processor number.
The proceedure is demonstrated in the video shown below. Before you start you need to save a file of all the settings on your Multi because the Firmware update will erase all settings. Once you have done the update you can reinstall all the settings.