Generally you can get away with it, but the KVA rating and the voltage drops proportionatley to the difference in voltage you apply.
The efficiency drops slightly also, although you may not notice it unless you run at max. current.
A transformer is designed to provide a certain magnetic field to overcome the iron losses etc and this depends on the turns/volt ratio and the voltage applied. You effectively doubling the turns/volt ratio by halving the voltage.
Al.
CNC, Mechatronics Integration and Custom Machine Design
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E.