Here is a state diagram for the HV ramping proceedure.

This diagram translates pretty directly into EPICS code (which doesn't exist yet).

You may note the difference between a "ramp up" and "ramp down".  In the case of ramping down, the voltage is set and then the ramp rate is set.  The opposite order of operations is done for ramping down.  This accounts for the case where you might be ramping when the operator requests a different state.  The ramp up rate might be used  briefly for a ramp down, but the ramp down rate will never be used for a ramp up.

Ramping to "OFF" is handled internally in the HV firmware... and I probably need to set the ramp down rate in that chain of commands as well...

Work in progress.