It is rather complex. Kodak had three round-mag projector series, plain Carousel for home use, Ektagraphic (US made) for office use (fancy electronics and automation, but less heavy duty than S-AV's), and the all-metal heavy duty S-AV Carousels (for professional display and PA use) made in Stuttgart.
The latter are widespread in Germany (every light and PA rental had them by the dozen), and are what is generally called "Carousel" hereabouts. They will work anywhere, as they have a 230/115V switch and C14 plug, and are my recommendation - hard to kill, gentle on the slides, and with all kinds of professional controller hookup (and the higher end one with automatically switching spare bulb).
Both plain Carousels and Ektagraphics were more strongly localized and usually have no adaptable power supply.
Stay clear of the consumer Carousels, these are dim and nonetheless prone to melt down your slides - but as they never were officially distributed this side of the pond, they should be rare.
You can sometimes find Ektagraphics in Germany, but quite a few of them are after market conversions from US grid power - probably once done for the US forces in Europe. If you buy one, make sure that it is a EU model where the original Kodak type plate says 230V (or 235, or 240) - conversions are a bit scary as they swapped out or re-soldered the transformer to get the voltage right, but did not address the 50Hz vs. 60Hz issues, so that the fan will run under speed, which will cause heat issues that might wear out your slides rather soon.
