European systems have one leg of that 240Vac "earthed." We would call it "grounded" in America. In America, neither leg of a 240Vac supply is grounded - each leg is at 120Vac to ground.
Now, if the case of the tool is connected to the leg which would have been earthed in Europe (for safety, dont'cha know)... well... I'd hate to be reading about "roast Duck." If the case is "double insulated," then experimentation would be a lot less chancy.
Mr. Duck, Sir, I regularly touch basis with some European electrical experts. If you can share the manufacturer and model number, I could possibly get some more specific information for you.