Hi Dennis

Here is a pretty good description of how a switched power supply works. (Not as accurate as the technical text I normally used for work, but at least it’s pretty easy to understand)

As you can see, unless it’s designed for dual voltage input, (More expensive) then only 1 input voltage is allowed. (There is a Big difference between a switch mode power supply and a universal switch mode power supply, therefore as was previously mentioned, do not assume anything)
http://en.wikipedia.org/wiki/Switched-mode_power_supply

Bill