You might take a look at the step down transformer, many times they have taps that allow changing the output voltage to correct for incoming power differences.
I'm a little confused about the RST terminals, normally that is the labeling on the main power terminals, but they may be something different on the Indramat. Instantly blowing a fuse would indicate a serious problem like a dead short or something.
Some pictures would be helpful. I'm unable to find any reference to a type TRK6 drive on the internet.