I'm no expert but to my knowledge metal cases always need to be grounded. Which is what I did with my 10" rack. I just bought a socket with a ground connector from an online store, although I'd be curious which exact cable is best practice. I don't have many things connected there anyway and the power supplies are outside of the rack.
FWIW the topic is quite a rabbit hole and for non-mobile metal cases (e.g. screwed on the wall) technically even an electrician seems to be needed.
I'm no expert but to my knowledge metal cases always need to be grounded. Which is what I did with my 10" rack. I just bought a socket with a ground connector from an online store, although I'd be curious which exact cable is best practice. I don't have many things connected there anyway and the power supplies are outside of the rack.
FWIW the topic is quite a rabbit hole and for non-mobile metal cases (e.g. screwed on the wall) technically even an electrician seems to be needed.