Smart BatteryProtect: Fuse in the GND cable

Hello everyone,

The instructions for the Smart BatteryProtect previously stated:
“6. Use the supplied 1,5mm2 wire for the GND connection, which should be connected directly to the battery negative terminal (or the chassis of a vehicle). No other equipment should be connected to this wire.”

In the current instructions, the following sentence was suddenly added:
“Note that the GND cable must be protected accordingly. A 300mA fuse is sufficient.”

Now I have questions:
Can anyone tell me what the background is? Is there a safety risk if there is no fuse? What does this mean for existing installations? Do the fuses have to be retrofitted?

It was by chance that I saw this. I didn’t actively notice anything about it in the app or anywhere else.

I would ask for clarification.

Thank you very much.

Best regards
Felix