How to input step change to 6RA70 used as static exciter controller?

We have a Simoreg 6RA7093-4GS22-0 that is being used as the controller for the field current/voltage for a static exciter on a steam turbine generator. 

I've not seen any application notes/guides for this particular use of the 6RA70. I need to input a step change as part of some model testing (need to record the step response). On a normal exciter controller I'd do this by increasing the terminal voltage setpoint by some percent increase.

Is anyone aware of the P-word value on the 6RA70 that I could change the value of to achieve the same response? I've looked at the application guide for using a 6RA70 as a DC gen-motor controller (not really the same thing, but similar) and in the manual tuning section for field current it mentions changing P601.01 to a base generator field current level of 25% rated. Would that work here?

-Thanks

Sorry for the delayed response. I really appreciate the help and the tip on using P601.03. I'm hoping to log into the Simoreg w/ DriveMonitor and view the values for a few different output levels to make sure I understand the relationship between P601.01 or .03 and the actual field current before messing with it.

Looking through the block diagram for current limitation (G161 in manual) it looks like the setpoint is checked against the min/max limits (as I'd expect) so I shouldn't be able to input anything too crazy but better safe than sorry.

Again, thank you very much for the input.