Now I've never used a RL02 drive on 50Hz power, but I'm 99% certain that the motor speed in a RL02 is determined by a servo loop, and thus not locked to a multiple of the AC frequency. I think the fan in a 50Hz RL02 will run a bit slower, but I don't think this will hurt anything. The power selector blocks on the back of the drive allow the selection of 90-128VAC or 180-256VAC. All my (US) RL02 drives have stickers on the back saying "120V, 60Hz", but I think the voltage is just the factor configuration and the "Hz" is just an anachronism. In my RL01/02 books the presence of a 50Hz option isn't even mentioned, though the tables specify that it's designed for 60Hz power. If folks know otherwise, they're welcome to correct me! John G. Zabolitzky