I've built four control panels for a facility we own in northern Italy and been there for the start up.
It looks like the basics have been covered already.
In the USA you can spec the ampacity that a machine supply requires and spec the motor horsepower (or wattage in Europe) on your drawings and expect that your journeyman electrician will select the appropriate wire. I found that to not be the case, at least where we had the equipment installed. When I arrived on site to supervise the installation I quickly discovered that their electricians, though union, would not select the wires, infact, they had no clue as to what was needed. Fortunately, I had access to the local codes, so I was able to add the spec. Every field wire on my drawings had to have a size spec added. The electricains I worked with were skilled at performing the mechanical aspects of the installation and hookup, but they really knew very little about electricity. That was my experience for that part of Italy, I don't know if that is generally the case or not. But assume that whoever installs the equipment may need to have even the little details on spec.