The SMU turns the chopper crown amps off after 30 minutes of inactivity.

To turn them off sooner you can do this:
  connect smuc
  <select option 2>
  waveMenu
  10
  0

  -----------------------

You will know they are shutdown because of these messages:

  fgen: Powered off the Crown Amp, axis= 0
  fgen: Powered off the Crown Amp, axis= 1

Here is the main waveMenu screen:

  FUNCTION GENERATOR MAIN MENU

0) Exit this menu
1) Print the DRAMA-fgen communications area
2) Print the fgen-ptos communications area
3) Change fgen waveform control parameters
4) Change fgen DREAM control parameters
5) Change fgen ACSIS/DRAMA control parameters
6) Change PTOS control parameters
7) Control fgen when in simulation
8) Control PTOS file writing: OFF
9) Fast startup
10) Stop Chopping
11) Look at arrays in detail
12) XYZ Table brake control
13) Change chopper PTOS constants
14) Show vmic3122 channels
15) Display the PTOS status

So option 10 is "Stop Chopping" and option 0 is "Exit this menu"

Craig