Hey Dennis,
it is true that for dimensioning of a VFD “for 2.2 kW mechanical power” spindle, the manufacturer takes inefficient spindles into account. But they have to do, they have no choice. That’s what a user can attach to the VFD anytime. You simply can’t dimensionate a VFD for best cases (best spindles) only. And no electrician will tell you it’s okay to attach an electric device to a supply circuit that does not fulfill the rated values. Also don’t forget apparent vs. real power, the apparent current is one that really flows! Even if you don’t pay for it so has to be taken into account when sizing wires, fuses, and supply circuits.
So all VFDs “for 2.2 kW mechanical power spindle” are in the range of being able to provide 4–5 kW electric power and thus to draw 22 – 27 A @200–250 V, and are therefore rated this way.
And those VFD “manufacturers” which produce VFDs that are not able to do this, well, they simply omit the input current rating and fool you this way. And offer VFDs at extremely low prices. That is not serious equipment, because you can have no knowledge of what they provide and what they draw, and when they will fail, making the price paid a bad decision, no matter how low it was.
I like to use hardware that I can rely on and sleep well then. I don’t like crap hardware whose “manufacturer” fools you with its (absent) rating values. I think if I pay €380 for a good VFD of industrial quality, I get something that I can rely on and sleep well. Look at the manual, 400 pages of dense information and leaves no questions open. In contrast, the VFDs of many cheap VFDs are just a joke. Not surprising that buyers search for the parameter settings at youtube – the VFD manual does not tell them in a good, didactical way, and the translation from chinese is often like a joke. My industrial VFD offers its 400-page manual in EN, DE, FR, IT, ES, CS, PL, RU: and this manual allows me to do everything from unpacking, connecting, sizing circuit, performing a first spindle test run, to sophisticated use cases. Such a manual is worth a lot, and takes part in justifying the price of the VFD.