Glow Startup and Shutdown Procedure
v 113000
Revised 1/3/01 GD

Revised 9/1/05 GD

Glow Startup:

B-top should be set up for helium and opened to the bottle

Turn off or close:
. GV3
. ratiomatics
. IGP2
. All diagnostic gatevalves
. TS
. TCI
. PCI
. Close GV1
. open sv3
. turn off IGP1
. open sv4 fully to 400 clicks (note: To modulate sv4 IGP1 must be off)
. close sv4 to 171 clicks
. Terry C-side shutter

Make sure A-port shutter is open and filter removed
so that the glow can be observed

Fill b-top helium --- leave connection to bottle open as we do with ECDC

Note that the RGA can be left on, but IGP1 should be monitored and not allowed to exceed 1.0e-5 Torr. If the pressure approaches this value SV4 should be closed somewhat more.

On the CRYBOR GDC screen
. make sure undervoltage limit is set to 150 V
. set supply voltage to 999 V
. set supply current to 200 mA
. turn on supply
. close RR1 and RR2
. no current increase from supply should be seen
. close CL1 and CL2 (Leave open to start to limit current until machine has been conditioned. Closing shorts out resistor in series with electrodes.)
. no current increase from supply should be seen
. Reset IGBT SW Control 1 and 2
. enter comp #1 and # 2 delta voltage to 200 volts (Lower these value as machine conditions and current is increased.)
. enable IGBT SW Control 1 and 2
. no current increase from supply should be seen

Go to the TORVAC gas fill screen
. set the fill request to 100 mT (Note: STATE must not be in STANDBY or ABORT)
. if necessary, clear gas fill fault
. select GDC on with TC6 feedback
        *This will turn off IGT and leave GAS FILL OK
. note that pressure is increasing on TC6
. once the pressure has stabilized at TC3 = 13 mT check if any current is flowing from glow electrodes
. if not pulse the gas puff button once to initiate the discharge
        * Note: For initial breakdown gas setpoint might have to be increased to 140 mT and pressure puffed as high as 60 mT on TC3 (~200 mT on TC6).  Once discharge is established, pressure can be dropped down as current is increased.
. set the fill request to 80 mT and wait for the pressure to stabilize

On the GDC screen
. bring the current up in 500 mA increments to 4000 mA while making sure no arcs are seen on the a-port and h-port TVs.

Glow Shutdown:

On the GDC screen
. drop current request to 0 mA
. when discharge goes out
. open RR1 and 2
. open CL1 and 2
. disable IGBT1 and 2

On the gas fill screen
. toggle GDS off

On the Torvac sceen
. when TC6 drops to 2 or 3 mT
. toggle on IGP2
. toggle on IGT
. when IGT drops below 1.e-5 Torr open GV1
. open GV3
. close SV3
. do not adjust SV4