The OHS course was done and good, but when you think about how many devices with PE wire are connected to sockets with two holes without PE and this is a mass phenomenon, it smells a bit fearful hypersensitivity. Tin PCs commonly used in homes are usually incorrectly plugged into ordinary sockets and somehow no one makes a problem out of it. Thanks for your comments, I will take them into account when installing the device permanently ;)
I have already ordered the thinnest 3x0.5mm2 cable I found for these 2.5W of power and when he gets there I will change him. OKAY?
Nobody is oversensitive here, if you invited a specialist for periodic electrical measurements to your home, he would point out the shortcomings because that's what he is for. The other side of the coin is the insurer who, if he does not see the paper, then ... but not about it.
The cable is selected for the protection, not the power of the device. You have a glass fuse with some value, say 1 A, you count the power of 230W - in a short circuit even more according to the characteristics of the fuse. We are talking mainly about fire protection for long-term load on the cable.
That's the theory and you practically do not meet cables smaller than 0.5mm2, so your choice will be good.