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Pre-Startup:

The beam is usually left powered on, but with the high voltage contactor ("Limit-Amp") open. This means that the following are typically already on:

• The main power breaker located in the high yard, controlled by the breaker handle labelled "DNB" at the front of the control room in the breaker rack. (red light indicates a closed state)
  
• The HV and Arc manual disconnects on the South cell wall at the lower level.
• The HV breaker in the center rack of the DNB rectifier cabinet at the lower level. 

The PC located in the upper level near the rear of the DNB (RFXDNB) should be running and the Java interface program should be open. If the DNB Java program ("DNBI4PSFC") is not running,
then the PC Java interface should be started by double clicking on the icon labelled "DNBI_PSFC" on the PC desktop.

Establish a VNC connection to the RFXDNB machine.

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Startup:

1. Set the dnb test shot number (typical C-Mod format; YYYMMDD300) by changing the value in the dnb tree (\dnb::top.current_shot:beam) using either the traverser or directly via mdstcl.
2. Confirm that PLC gate valve setting is "manual", and that the calorimeter is positioned IN the beam line on the Main DNBPLC screen.
3. On the RFXDNB java screen, turn on "Aux. PS" and "Heater PS".  Confirm heater current is 110-118 A.
4. Check the beam gas and auxiliary system operation by firing test shot(s) (i.e. independent of C-Mod shot cycles) into the calorimeter with the gate valve disabled. The test shots are typically operated in "external mode" by executing the TCL macro script (/usr/local/cmod/codes/dnb/dnb_cond_shot.tcl). Make sure that there are indications of beam gas flow, MIPS power supply voltage, and third grid voltage. Gas flow should be ~500 sccm for the anode and ~120 sccm for the cathode.
   
5. If all systems look okay and gas flow is reasonable, then close DNB contactor by pressing the "Close LimitAmp" button on the PLC Power screen.
6. Fire a test shot with power. Verify operation of all of the beam systems including neutral beam, the high voltage system and the arc system.
7. When operating with power, note the shot timer at the bottom of the right sidebar in the PLC screen. Do not fire the beam more frequently than every three minutes as indicated by the shot timer. This is a voluntary compliance  system.
   

C-Mod Syncronized Operation into Plasma

      

1. Move the calorimeter into the beam line by pushing the "in" button on the Main PLC screen. Confirm that calorimeter moves in to the beamline by watching the position of the graphic.
2. Set desired beam timing parameters; Set beam pulse length and modulation on the RFXDNB java screen and set beam_on, beam_length, nodes in DNB tree.
3. Turn on the following nodes in the DNB tree:
         \dnb::top.dnb_eng.camac:BIRA_H910
         \dnb::top.dnb_eng.camac:DECODER_01
         \dnb::top.dnb_eng.camac:J221_01
         \dnb::top.dnb_eng.camac:J221_01:output_05
         \dnb::top.dnb_eng.camac:J221_01:output_08
         \dnb::top.dnb_eng.camac:J221_01:output_09
         \dnb::top.dnb_eng.camac:J221_01:output_10
         \dnb::top.dnb_eng.camac:J221_01:output_11
         \dnb::top.dnb_eng.camac:J221_01:output_12
         \dnb::top.dnb_eng.camac:L8212_01
         \dnb::top.dnb_eng.camac:T4012

4. Switch relevant scopes to look at'current_shot("cmod")' rather than "dnb" (if they aren't already)
5. Confirm that bending magnet is turned on for entire beam pulse.  Set BM_state node on/off to reflect bending magnet state. Confirm that spectrometer and automatic spectral analysis are working.
6. Finally, set up for firing beam into C-Mod plasma (after having fired the beam into calorimeter under C-Mod shot cycle control; Confirm beam pulse length setting (do not overheat inboard wall); For long-pulse operation, confirm that inboard wall pyrometer and beam interlock system is working, Confirm that bending magnet is turned on for entire beam pulse and set BM_state node "on". Confirm beam_on, beam_length, and beam_delay settings in tree.
7. Request permission from session leader to fire beam into plasma, and request from the physop an enable for the DNB gate valve, and suggest that physop add 2-3 ms to prefill gas puff.  
   
8. Move calorimeter out of beamline and set the  PLC gate valve to "Automatic" on DNBPLC control screen.
   

C-Mod Syncronized Operation into calorimeter

   To stop firing into C-Mod plasma, but continue firing into calorimeter:

1. Request physop disable DNB gate valve, and suggest that physop subtract 2-3 ms from prefill gas puff.
2. Set PLC gate valve to "Manual" on DNBPLC control screen.
3. Move calorimeter into beamline.
   

   Optional:
       Turn off aforementioned nodes in DNB tree to disable firing with
        C-Mod shot cycle.