BaBar Drift Chamber

Returning to Running Operations

Last Updated: January 10, 2007 by Karl Bouldin

MAINTAIN THE LOGBOOK

Before starting these procedures, please make an entry in the logbook.

REFILL THE DCH GAS SYSTEM

You do not have to do it by yourself, but please contact DCH Gas System experts (Jim McDonald, Karl Bouldin) to ensure this is being done.

TURN ON THE HIGH VOLTAGE

1. Check that the conditions are right to do so.
2. Remember the LEMO terminators we removed before shutdown? Now it is time to put them back.
3. Try ramping up HV in EPICS
   • In EPICS, go to: odc_main -> DCH -> High Voltage;
   • If the button under Global Mode is YES, press it once to bring to NO;
   • Press on Running under Set HV To to ramp on DCH;

Note: if you fail to ramp up the HV, try the following:

• Power cycle the CAEN (not sure if it's necessary, but that's harmless)
• Reboot the dch-mon IOC
• Check all the CAEN constant in EPICS (HV -> More (right click) -> Board 0-6). Compare with values from the HV Controls Web page Just compare with the values taken from this web page:
• reload these constants to the CAEN with EPICS

Hints to resolve some common HV problems are available.

UPDATE ALARM HANDLER CONFIGURATION

It's preferable to coordinate the actions with DCH EPICS experts (Vincent Poireau, Karl Bouldin)

Remember that before shutdown we changed to ALH configuration to avoid alarms caused by removing the LEMO connectors? It is time to update it again!

• Login on bbr-refsun.slac.stanford.edu or bbr-reflin.slac.stanford.edu
• cd /nfs/bbr-srv01/u1/babar/boot/apps/dch-mon/alh
• rm dchmon.alh
• ln -s dchmon-normailRunning.alh dchmon.alh
• Restart the alarm handler in IR2: startalh on bbr-con01

Restart cron jobs for dch-mon and dch-gas

• Log on to bbr-dev100 as babardch
• crontab -e
• remove # signs from lines for each job.
• Save and quit.

• Log on to bbr-gassun1 as babardch
• crontab -e
• remove # signs from lines for each job.
• Save and quit.

MAINTAIN THE LOGBOOK

Please make an entry in the logbook when these procedures are completed.