The highest voltages/currents of the power supplies I worked on:
1. 15 kV, 1.5A (variable, regulated) Input was 3 phase 208 at 60A
The other one was 208 3 Phase, 90A input No problem with HV except cables were cut and tube popped out of its socket
We bought it at an auction and lots of wires were cut. There was a hidden connector.
Management had little hope of me getting it working.
2. 100 kV at 0.1 A (variable) (x-ray generator)
3. 1000 W into 50 ohms, RF @ 13.56 MHz, tube