Kai
I can convert it easily in my head ( I am german):) so I use what ever is posted.

If I want millivolt resolution I will use millivolts as my base.
if I want volts say -1400 v on the focus anode I will use volts. If I just want to say be careful that anode pin has about -1.4 kv the use of kv would better alert someone to the danger.

Eric:
The reference to welders was that the original poster’s company uses welders as the supply to test these rotors before they are assembled into the motors.

Shunts: I have a drawer full of them in various ratings to 1000 amps. They come in standard 50 mv Full Scale Deflection ratings so they can be directly connected to a 50 mv meter movement with the appropriate scale on it for a direct reading system.
Most shunts are ac 50 /60 Hz or dc rated.

The biggest problem that I saw with them in the power industry was the misapplication of them by placing them in a high voltage line resulting in high voltage (575 vac) in a supposed low voltage area of the instrumentation package.