Hallo Mark and Robbie,  Robbie's memory is perfect and Mark is right!
The first step, when I got the piano uncrated, was to use a step-down
transformer which had also all needed plugs and sockets.  This worked
perfectly.

But my wife did not like the rather bulky transformer on the carpet.
The more important reason to have the motor rewound was electrical
safety.  The transformer was an auto-transformer type, so one could
not be sure about hot and neutral, because the power plugs we use in
Germany do not provide keying.

In order to preserve authenticity the original name plate was kept
and supplemented by another plate that informed about the rewinding
procedure.

Best regards,
Walter Tenten
Germany