CAT Chat Minutes

October 27, 2003 


Information and Follow-up

User asked what the acronyms "PAR" mean?

Particle Accumulation Ring (PAR)

Randy Alkire noted that after a power failure, a spike is caused when the power comes back. Has anyone else noticed anything like this?

No one in the group replied that they had noticed the spike.  Bill Wesolowski is looking into this issue with Randy.



Machine Stats R. Klaffky:

Delivered beam:  537.75 hrs.
Percentage of scheduled time:  97.24% [ 96.58 % last week]
Downtime during period:  13.37 hrs.
Mean time between faults:  41.37 hrs. [31.48hr last week]


#29 10/21 16:00 to 10/23 13:48 45.80 HR [PS] | 1.87 hr S18/19 Raw Trip and then MPS problem

#30 10/23 15:40 to 10/27 08:00 89.33 HR Intentional Dump


Beamline Downtime Report:  Summary period 10/17-23/2003

Number Date Time Beamline Description Downtime Group
000245 10/17/03 01:04 03-ID Recurring PSS both-switch and mixup faults requiring replacement of shutter limit switches 4:36 ES/PS
000264 10/19/03 01:09 - Cryosystem difficulties requiring call-in of ME group for help troubleshooting 2:30 Beamline
000265 10/19/03 15:04 13-BM Serious fault #32: PSS Chain B Dead 0:21 ES/PS
000266 10/19/03 21:38 08-ID Serious PSS faults and DIW fault requiring rebalancing of the water system 0:24 ME
000267 10/20/03 09:25 13-BM PSS replacement of watchdog relay 0:20 ES/PS
000268 10/21/03 21:35 18-ID Steering software malfunction prohibited beamline from steering (impact to secondary tasks) 0:59 MCR/OPS
000269 10/23/03 16:05 - Door disable button had been pushed 0:38 Beamline

Draft Direct Injection Policy - R. Klaffky:  Policy was discussed at OPS Directorate this morning. Below follows the text which will also be sent out on CAT-net.

Direct Injection Policy: Periodically high voltage components used for PAR injection / extraction fail, generally requiring several hours to effect repairs. To alleviate the impact of this condition on storage ring operation, a PAR bypass direct booster injection procedure is available, allowing the storage ring to be filled. Bunch purity is not maintained for this mode of operation. The purpose of the policy stated below is to define the conditions under which injection into the storage ring will take place using direct booster injection.

Major repairs generally involve access into the PAR accelerator enclosure. This policy addresses only those repairs requiring tunnel access.

If the stored beam current is expected to fall below 60 mA prior to the expected completion of repairs, a fill-on-fill using direct booster injection will be performed prior to the initiation of in-tunnel repairs, with a minimum of 30 minutes advanced notice.

Otherwise, if the PAR fails with beam stored in the storage ring, repairs will commence, and top-up will be aborted. For 24-bunch mode the storage ring coupling will be increased to 4% to improve lifetime.

If the stored beam is lost while repairs are underway: Repairs will continue if they are expected to be completed within 90 minutes.

If repairs are expected to require more than 90 minutes, the linac/ PAR enclosure will be secured, and direct booster injection will be used to fill the storage ring. Once stable stored beam is attained, repairs on the PAR will recommence.

Roger showed the APS FY2004 Long Range Operating Schedule (October 2003-2004) and went over activities of the current week.

Safety B. Glagola: Bruce reported that the USDA has notified him that the approval for testing domestic soil has been okayed.

Bruce would like to inform the group that he will take vacation from November 8-16, 2003. He asks if you have any safety issues/concerns, please contact Elroy Chang, ext. 6714.  If you are working on ESAFs, dont forget to submit them early.